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[GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340333] Thu, 24 January 2019 22:40 Go to next message
BobDunahugh is currently offline  BobDunahugh   United States
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Registered: October 2010
Location: Cedar Rapids, IA
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The stock 455 that we have is good to 5000 RPM's. The stock 403 is fine to 6000 RPM's. But with the cam profiles that our engines have. There is no reason to go much be on 3900 RPMs. Engine cam profiles are based on many factors. But mostly on how the engine is going to be used, engine cubic inches, final drive ratio, tire diameter, and expected gross weight to be moved. There are more. But these are the main ones. GM had to make a car engine perform the duties of a truck engine. Our engine were built to produce it's peak horsepower, and torque in the 2400, to 2800 RPM range. We drive torque. Not horsepower. Torque is what gets us up that next hill. A torque chart starts at 600 RPM's. And continues to climb till the engine hits it's peak torque RPM point. Then the torque produced will state to drop off. The torque curve chart will be in the shape of a bell. The cam shaft lob profile is the magic that make our engines able to perform to move us along so well. Whenever I start climbing long steep grades. Sift to second. Run the RPM's up to 3700, to 4000 RPM's till I get to the top. And never have the throttle more then half open. I have a personal game I play. In trying to see how high I can get the number of cars that I can get to go around me before I get to the top of the pass. ( GRIN ) When someone says that any RPM's over 3300 RPM's. will just burn the engine up. Due to high piston speeds. That is absolutely, positively not true. Bob Dunahugh 78 Royale
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Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340340 is a reply to message #340333] Fri, 25 January 2019 11:09 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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Glad to know someone is doing it that way!
Makes me nervous to rev over 3k!

That being said I've never had a hill that I have any trouble at all getting up, sometimes in second bur normally in 3rd.
I've never revved mine over 3100 and never had an issue.
Maybe next time I;ll rev it up for the hell of it!


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340354 is a reply to message #340340] Fri, 25 January 2019 17:19 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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I just used a quick 'n dirty formula and figured both 455 and 403 engines
piston speed in surface feet per minute. Most engine builders agree that
you can safely run an engine under average load at 5000 surface per minute.
Neither 455 engines nor 403's come anywhere near that speed at 4000
rpm. 455 =2833.3 sfm vs 403 = 2256.6 sfm.
Bob is correct, don't worry about over revving either engine. If you really
want to worry about something, worry about lugging your engine and not keep
its oiling system full.
Jim Hupy

On Fri, Jan 25, 2019, 9:09 AM Justin Brady Glad to know someone is doing it that way![/color]
> Makes me nervous to rev over 3k!
>
> That being said I've never had a hill that I have any trouble at all
> getting up, sometimes in second bur normally in 3rd.
> I've never revved mine over 3100 and never had an issue.
> Maybe next time I;ll rev it up for the hell of it!
> --
> Justin Brady
> http://www.thegmcrv.com/
> 1976 Palm Beach 455
>
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Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340357 is a reply to message #340354] Fri, 25 January 2019 17:50 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
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Do most of you have tacks to see how fast you are running?
I would think as light as our coaches are unless we are towing we should be
able to keep up with the big heavy diesel pushers.
I have driven mine about 300 miles total and none of it in hills. Just
looking at the horsepower ratings and weight I should have more power per
pound than a 400 horse 32000 lb SOB.
Am I wrong? I would think this should climb more like a minivan with a
small engine. Is the problem that we really need a 5-speed transmission
with a gear between each of what we have?

On Fri, Jan 25, 2019 at 3:16 PM James Hupy wrote:

> I just used a quick 'n dirty formula and figured both 455 and 403 engines
> piston speed in surface feet per minute. Most engine builders agree that
> you can safely run an engine under average load at 5000 surface per minute.
> Neither 455 engines nor 403's come anywhere near that speed at 4000
> rpm. 455 =2833.3 sfm vs 403 = 2256.6 sfm.
> Bob is correct, don't worry about over revving either engine. If you really
> want to worry about something, worry about lugging your engine and not keep
> its oiling system full.
> Jim Hupy
>
> On Fri, Jan 25, 2019, 9:09 AM Justin Brady
>> Glad to know someone is doing it that way!
>> Makes me nervous to rev over 3k!
>>
>> That being said I've never had a hill that I have any trouble at all
>> getting up, sometimes in second bur normally in 3rd.
>> I've never revved mine over 3100 and never had an issue.
>> Maybe next time I;ll rev it up for the hell of it!
>> --
>> Justin Brady
>> http://www.thegmcrv.com/
>> 1976 Palm Beach 455
>>
>> _______________________________________________
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340363 is a reply to message #340357] Fri, 25 January 2019 18:55 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
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Senior Member
johnd01 wrote on Fri, 25 January 2019 18:50
Do most of you have tacks to see how fast you are running?
I would think as light as our coaches are unless we are towing we should be able to keep up with the big heavy diesel pushers.
I have driven mine about 300 miles total and none of it in hills. Just looking at the horsepower ratings and weight I should have more power per pound than a 400 horse 32000 lb SOB.
Am I wrong? I would think this should climb more like a minivan with a small engine. Is the problem that we really need a 5-speed transmission with a gear between each of what we have?

*John Phillips*
John,

Very few of us have tachometers. I do because I am an engine dweeb and have been since about age 10. I made a living at it since then, and have a lot of experience to offer.

Multi-speed transmission lore is an adjunct of the emissions age. OK, Model Ts had a 2 speed system but a top speed of about 45. Other than that (and the two speed early automatics) the world has gotten by with three speed transmissions until we tried to beat the little horseys harder and found that the ran better when bred for a narrow performance band. The Oldsmobile engines of the coach period are not those. They are not quarter horses that can want to go for a sprint, they are the Percherons and Clydesdales of the passcar engine world. Even as big as they are, they still are not steam engines that do maximum torque at zero speed. They ask for help there. When these coaches went out on the road, gas was relatively in expensive and the speed limits in most states were 65~70. Then came the Carter/Arab oil embargo......

The coaches had launched with the 3.07 rear end (final drive, ours isn't in the rear). Even at 70, that is a little low, but it was what GM had in inventory from the Toronado towing package. It was accepted based on the original 19 and 22 foot models. It was actually wrong then. Now the situation is worse. Twenty-Three footers are rare and the 26s can tip a scale at #12,000+.

My coach is a very light 23. With the stock cam, it suffered at 60~65. That was 21~2200 with the converter slip (it is not fully engaged at those road speeds). The engine was not comfortable, but it was not happy either for the 70K+ miles we drove here. Last year, she failed a piston. I believe it was a result of having to run at low piston speeds with high BMEP, but that is just an expert's opinion. Now, she has a new cam (thanks to Dick Paterson recommendation) and is happy at the too low speed such that she doesn't like running there (and will tell you, if you listen) but she is more comfortable.

As soon as the situation allows, I am going to install a 3.55. Remember, she is a 9400# coach. A 3.42 (old GM number) would be marginally better than stock, but not quite there for this weight. If you have a later build and it will be heavier, I very seriously suggest that you thing about spring for a 3.70 before you do anything else. If the coach is a 403, you should really consider it before the next oil change.

Even before getting the correct cam, we could keep up with the monster coaches over the Big Horn (9200MSL fron GPS) and pass some little J-cars at ~8500MSL. We do loose out at about 10KMSL because the diesels are all turbocharged (don't think I haven't thought about that) but the final drive would still be wrong).

That is this dyno-lab refugee and 14 year GMC owner's take on the whole thing. But you are free to waste your money where you please. (JimK is the source to the high number final drives and I have no interest in that situation.)

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340367 is a reply to message #340333] Fri, 25 January 2019 20:56 Go to previous messageGo to next message
BobDunahugh is currently offline  BobDunahugh   United States
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
Senior Member

The best way to get to the top of the mountain. Several years ago. I was climbing out of Denver. Up to the Eisenhower tunnel. That's a long steep climb. While pulling one of my Yenko's on a trailer. With a GVW of 17,000 LBS. 3:70 FD, and a 403. I put the trans in first. Ran the 403 up to 4400 RPM's. Then used no more the half throttle. As for speed. Got what I got. Didn't care. So what was going on here. First. With half throttle. I was reducing the amount of BTU's going into the engine. With the RPM's up. The engine water pump was taking more engine heat to the radiator. The engine fan was pulling more air in to keep the engine cooler. The trans fluid pump was also caring more heat off to the trans cooler. Jim Hupy's e-mail covered piston FPM well. GM should have never installed a 3:07 FD in these GMC's that weigh 11,000 lbs. The 3:21, 3;42, 3:55 are of alittle help. Towing or not. The 3:70 has been proven to be the best choice. Also with gas mileage going up. Because your running a higher intake manifold vacuum. Bob Dunahugh 78 Royale
________________________________
From: Bob Dunahugh
Sent: Thursday, January 24, 2019 10:40 PM
To: gmclist@list.gmcnet.org
Subject: Tid Bits. Should we be concerned about over reving our Olds engines.

The stock 455 that we have is good to 5000 RPM's. The stock 403 is fine to 6000 RPM's. But with the cam profiles that our engines have. There is no reason to go much be on 3900 RPMs. Engine cam profiles are based on many factors. But mostly on how the engine is going to be used, engine cubic inches, final drive ratio, tire diameter, and expected gross weight to be moved. There are more. But these are the main ones. GM had to make a car engine perform the duties of a truck engine. Our engine were built to produce it's peak horsepower, and torque in the 2400, to 2800 RPM range. We drive torque. Not horsepower. Torque is what gets us up that next hill. A torque chart starts at 600 RPM's. And continues to climb till the engine hits it's peak torque RPM point. Then the torque produced will state to drop off. The torque curve chart will be in the shape of a bell. The cam shaft lob profile is the magic that make our engines able to perform to move us along so well. Whenever I start climbing long steep grades. Sift to second. Run the RPM's up to 3700, to 4000 RPM's till I get to the top. And never have the throttle more then half open. I have a personal game I play. In trying to see how high I can get the number of cars that I can get to go around me before I get to the top of the pass. ( GRIN ) When someone says that any RPM's over 3300 RPM's. will just burn the engine up. Due to high piston speeds. That is absolutely, positively not true. Bob Dunahugh 78 Royale
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Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340384 is a reply to message #340367] Sat, 26 January 2019 11:20 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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I wouldn't be without a tack and I wouldn't run a 455 at or above 4000 rpm for any length of time especially in these western mountains with the pedal to the metal. If you do and the motor wasn't modified for high rpm you may be sorry you did.3000 is a lot safer.

Roy Keen Minden,NV 76 X Glenbrook
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340385 is a reply to message #340384] Sat, 26 January 2019 11:50 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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I have four extra gages on my 78 Royale 403. Vacuum, Tachometer,
Transmission fluid temperature at the Ragusa finned aluminum pan, and final
drive oil temperature. The Tachometer and Vacuum gage are mounted between
the drivers side windshield and the horse collar that surrounds the dash.
The oil gages are mounted where the ash tray used to be.
I often run my 403 between 3000 and 3600 rpm. With the final drive
and wheel and tire combinations that I run, that is between 62 and 75 miles
per hour. The 403 is a happy camper in that rpm range.
The 455 will not be hurt a bit at those rpms either.
If I am climbing long continuous grades, I will manually downshift and
run the 403 at 4200 - 4500 rpm at 10 to 12 inches of mercury ( throttles
1/2 way open) for long stretches. My original engine is still equipped with
a quadrajet carb and Doug Thorley Coated headers, dual mufflers and a 2
3/4" tail pipe. It has over 130,000 miles and burns a quart of 20 -50
Valvoline Dino oil in about 1500 miles. Last time I checked compression, it
pumped over 150 psi across the board. I can't complain about that
performance. The best modification I ever did was the 3:70 final drive
gearing.
Jim Hupy

On Sat, Jan 26, 2019, 9:21 AM roy keen I wouldn't be without a tack and I wouldn't run a 455 at or above 4000 rpm[/color]
> for any length of time especially in these western mountains with the pedal
> to the metal. If you do and the motor wasn't modified for high rpm you may
> be sorry you did.3000 is a lot safer.
> --
> Roy Keen
> Minden,NV
> 76 X Glenbrook
>
> _______________________________________________
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Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340401 is a reply to message #340385] Sun, 27 January 2019 03:55 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
Messages: 354
Registered: July 2017
Location: Sacrameot
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Senior Member
Matt

> I have the original Avion VIN A26000 with a GMC Firewall VIN of
> TZE064V10116 with a 455 and headers. Given that our drive wheels are
> about 15% larger than the car version the 3.07 would be like having a 2.60
> in the Toronado towing package. Not much of a towing package. So unless you
> are going to do a lot of flatland 80 mph driving in a very light coach a
> higher final drive ratio would be in order. A 3.53 would match the Toronado
> towing package . Will a higher final drive ratio take some of the strain
> off of the transmission and the rest of the drivetrain?

* My coach is a very light 23. With the stock cam, it suffered at 60~65.
That was 21~2200 with the converter slip (it is not fully engaged at those*
*road speeds). *
Are you implying that you need more RPMs to get the torque converter to
lock up/not slip? Is there a lockup clutch in our converter?

On Sat, Jan 26, 2019 at 9:48 AM James Hupy wrote:

> I have four extra gages on my 78 Royale 403. Vacuum, Tachometer,
> Transmission fluid temperature at the Ragusa finned aluminum pan, and final
> drive oil temperature. The Tachometer and Vacuum gage are mounted between
> the drivers side windshield and the horse collar that surrounds the dash.
> The oil gages are mounted where the ash tray used to be.
> I often run my 403 between 3000 and 3600 rpm. With the final drive
> and wheel and tire combinations that I run, that is between 62 and 75 miles
> per hour. The 403 is a happy camper in that rpm range.
> The 455 will not be hurt a bit at those rpms either.
> If I am climbing long continuous grades, I will manually downshift and
> run the 403 at 4200 - 4500 rpm at 10 to 12 inches of mercury ( throttles
> 1/2 way open) for long stretches. My original engine is still equipped with
> a quadrajet carb and Doug Thorley Coated headers, dual mufflers and a 2
> 3/4" tail pipe. It has over 130,000 miles and burns a quart of 20 -50
> Valvoline Dino oil in about 1500 miles. Last time I checked compression, it
> pumped over 150 psi across the board. I can't complain about that
> performance. The best modification I ever did was the 3:70 final drive
> gearing.
> Jim Hupy
>
> On Sat, Jan 26, 2019, 9:21 AM roy keen
>> I wouldn't be without a tack and I wouldn't run a 455 at or above 4000
> rpm
>> for any length of time especially in these western mountains with the
> pedal
>> to the metal. If you do and the motor wasn't modified for high rpm you
> may
>> be sorry you did.3000 is a lot safer.
>> --
>> Roy Keen
>> Minden,NV
>> 76 X Glenbrook
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
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>>
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340403 is a reply to message #340401] Sun, 27 January 2019 09:01 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
johnd01 wrote on Sun, 27 January 2019 04:55
Matt

> I have the original Avion VIN A26000 with a GMC Firewall VIN of
> TZE064V10116 with a 455 and headers. Given that our drive wheels are
> about 15% larger than the car version the 3.07 would be like having a 2.60
> in the Toronado towing package. Not much of a towing package. So unless you
> are going to do a lot of flatland 80 mph driving in a very light coach a
> higher final drive ratio would be in order. A 3.53 would match the Toronado
> towing package . Will a higher final drive ratio take some of the strain
> off of the transmission and the rest of the drivetrain?

* My coach is a very light 23. With the stock cam, it suffered at 60~65.
That was 21~2200 with the converter slip (it is not fully engaged at those*
*road speeds). *
Are you implying that you need more RPMs to get the torque converter to
lock up/not slip? Is there a lockup clutch in our converter?
Yes John,

That is exactly what I am saying and there was no lock-up version of torque converter for transmissions of this era. That did not come along until CAFE hit the scene. (Unless you were brave enough to try to drive a street car with a "Clutch-Flyt".

Matt

Quote:
On Sat, Jan 26, 2019 at 9:48 AM James Hupy wrote:

> I have four extra gages on my 78 Royale 403. Vacuum, Tachometer,
> Transmission fluid temperature at the Ragusa finned aluminum pan, and final
> drive oil temperature. The Tachometer and Vacuum gage are mounted between
> the drivers side windshield and the horse collar that surrounds the dash.
> The oil gages are mounted where the ash tray used to be.
> I often run my 403 between 3000 and 3600 rpm. With the final drive
> and wheel and tire combinations that I run, that is between 62 and 75 miles
> per hour. The 403 is a happy camper in that rpm range.
> The 455 will not be hurt a bit at those rpms either.
> If I am climbing long continuous grades, I will manually downshift and
> run the 403 at 4200 - 4500 rpm at 10 to 12 inches of mercury ( throttles
> 1/2 way open) for long stretches. My original engine is still equipped with
> a quadrajet carb and Doug Thorley Coated headers, dual mufflers and a 2
> 3/4" tail pipe. It has over 130,000 miles and burns a quart of 20 -50
> Valvoline Dino oil in about 1500 miles. Last time I checked compression, it
> pumped over 150 psi across the board. I can't complain about that
> performance. The best modification I ever did was the 3:70 final drive
> gearing.
> Jim Hupy
>
> On Sat, Jan 26, 2019, 9:21 AM roy keen
>> I wouldn't be without a tack and I wouldn't run a 455 at or above 4000
> rpm
>> for any length of time especially in these western mountains with the
> pedal
>> to the metal. If you do and the motor wasn't modified for high rpm you
> may
>> be sorry you did.3000 is a lot safer.
>> --
>> Roy Keen
>> Minden,NV
>> 76 X Glenbrook
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--

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Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340405 is a reply to message #340403] Sun, 27 January 2019 09:48 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Depending upon whether or not your torque converter is original or has been
upgraded, you probably have a converter with a 2500 rpm stall speed. That
is NOT TO SAY THAT IT "LOCKS UP" because it never really does that. There
is always some slippage between engine speed and transmission input shaft
speed.
A true "lock up" converter is the same as a manual clutch (very little
slippage).
So, at 2100 rpm, your engine is turning faster than your transmission
input shaft, and some heating of the transmission fluid is occurring as a
result of that slippage. Engineers have to account for energy loss through
moving something by applying a force (work) or by heat loss.
Jim Hupy


On Sun, Jan 27, 2019, 7:12 AM Matt Colie johnd01 wrote on Sun, 27 January 2019 04:55[/color]
>> Matt
>>
>>> I have the original Avion VIN A26000 with a GMC Firewall VIN of
>>> TZE064V10116 with a 455 and headers. Given that our drive wheels are
>>> about 15% larger than the car version the 3.07 would be like having a
> 2.60
>>> in the Toronado towing package. Not much of a towing package. So
> unless you
>>> are going to do a lot of flatland 80 mph driving in a very light
> coach a
>>> higher final drive ratio would be in order. A 3.53 would match the
> Toronado
>>> towing package . Will a higher final drive ratio take some of the
> strain
>>> off of the transmission and the rest of the drivetrain?
>>
>> * My coach is a very light 23. With the stock cam, it suffered at 60~65.
>> That was 21~2200 with the converter slip (it is not fully engaged at
> those*
>> *road speeds). *
>> Are you implying that you need more RPMs to get the torque converter to
>> lock up/not slip? Is there a lockup clutch in our converter?
>
> Yes John,
>
> That is exactly what I am saying and there was no lock-up version of
> torque converter for transmissions of this era. That did not come along
> until
> CAFE hit the scene. (Unless you were brave enough to try to drive a street
> car with a "Clutch-Flyt".
>
> Matt
>
> Quote:
>> On Sat, Jan 26, 2019 at 9:48 AM James Hupy wrote:
>>
>>> I have four extra gages on my 78 Royale 403. Vacuum, Tachometer,
>>> Transmission fluid temperature at the Ragusa finned aluminum pan, and
> final
>>> drive oil temperature. The Tachometer and Vacuum gage are mounted
> between
>>> the drivers side windshield and the horse collar that surrounds the
> dash.
>>> The oil gages are mounted where the ash tray used to be.
>>> I often run my 403 between 3000 and 3600 rpm. With the final
> drive
>>> and wheel and tire combinations that I run, that is between 62 and 75
> miles
>>> per hour. The 403 is a happy camper in that rpm range.
>>> The 455 will not be hurt a bit at those rpms either.
>>> If I am climbing long continuous grades, I will manually
> downshift and
>>> run the 403 at 4200 - 4500 rpm at 10 to 12 inches of mercury (
> throttles
>>> 1/2 way open) for long stretches. My original engine is still
> equipped with
>>> a quadrajet carb and Doug Thorley Coated headers, dual mufflers and a
> 2
>>> 3/4" tail pipe. It has over 130,000 miles and burns a quart of 20 -50
>>> Valvoline Dino oil in about 1500 miles. Last time I checked
> compression, it
>>> pumped over 150 psi across the board. I can't complain about that
>>> performance. The best modification I ever did was the 3:70 final drive
>>> gearing.
>>> Jim Hupy
>>>
>>> On Sat, Jan 26, 2019, 9:21 AM roy keen
>>>> I wouldn't be without a tack and I wouldn't run a 455 at or above
> 4000
>>> rpm
>>>> for any length of time especially in these western mountains with the
>>> pedal
>>>> to the metal. If you do and the motor wasn't modified for high rpm
> you
>>> may
>>>> be sorry you did.3000 is a lot safer.
>>>> --
>>>> Roy Keen
>>>> Minden,NV
>>>> 76 X Glenbrook
>>>>
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
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>>>
>>
>>
>> --
>>
>> *John Phillips*
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
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>
>
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
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Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340410 is a reply to message #340403] Sun, 27 January 2019 12:13 Go to previous messageGo to next message
Kosier is currently offline  Kosier   United States
Messages: 834
Registered: February 2008
Karma: 1
Senior Member
Matt,

Have you checked the Packard Ultramatic of the mid 50s? I overhauled one
back in the early 60s and I seem to recall a clutch in the converter.

Gary Kosier

> Yes John,
>
> That is exactly what I am saying and there was no lock-up version of
> torque converter for transmissions of this era. That did not come along
> until
> CAFE hit the scene. (Unless you were brave enough to try to drive a street
> car with a "Clutch-Flyt".
>
> Matt
>
> Quote:
>> On Sat, Jan 26, 2019 at 9:48 AM James Hupy wrote:
>>
>>> I have four extra gages on my 78 Royale 403. Vacuum, Tachometer,
>>> Transmission fluid temperature at the Ragusa finned aluminum pan, and
>>> final
>>> drive oil temperature. The Tachometer and Vacuum gage are mounted
>>> between
>>> the drivers side windshield and the horse collar that surrounds the
>>> dash.
>>> The oil gages are mounted where the ash tray used to be.
>>> I often run my 403 between 3000 and 3600 rpm. With the final
>>> drive
>>> and wheel and tire combinations that I run, that is between 62 and 75
>>> miles
>>> per hour. The 403 is a happy camper in that rpm range.
>>> The 455 will not be hurt a bit at those rpms either.
>>> If I am climbing long continuous grades, I will manually
>>> downshift and
>>> run the 403 at 4200 - 4500 rpm at 10 to 12 inches of mercury (
>>> throttles
>>> 1/2 way open) for long stretches. My original engine is still equipped
>>> with
>>> a quadrajet carb and Doug Thorley Coated headers, dual mufflers and a
>>> 2
>>> 3/4" tail pipe. It has over 130,000 miles and burns a quart of 20 -50
>>> Valvoline Dino oil in about 1500 miles. Last time I checked
>>> compression, it
>>> pumped over 150 psi across the board. I can't complain about that
>>> performance. The best modification I ever did was the 3:70 final drive
>>> gearing.
>>> Jim Hupy
>>>
>>> On Sat, Jan 26, 2019, 9:21 AM roy keen
>>>> I wouldn't be without a tack and I wouldn't run a 455 at or above
>>>> 4000
>>> rpm
>>>> for any length of time especially in these western mountains with the
>>> pedal
>>>> to the metal. If you do and the motor wasn't modified for high rpm
>>>> you
>>> may
>>>> be sorry you did.3000 is a lot safer.
>>>> --
>>>> Roy Keen
>>>> Minden,NV
>>>> 76 X Glenbrook
>>>>
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>>
>>
>> --
>>
>> *John Phillips*
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340411 is a reply to message #340405] Sun, 27 January 2019 13:25 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
Messages: 4452
Registered: November 2009
Karma: -8
Senior Member
Hi, Jim!

It my reasoning is correct about stall speed, we would improve overall performance if we choose a final drive ratio that would our RPM at least at torque converter stall speed at say 55-60 MPH?

Mac Macdonald in OKC
The Money Pit
76 ex Palm Beac

Sent from my iPhone

On Jan 27, 2019, at 09:45, James Hupy wrote:

Depending upon whether or not your torque converter is original or has been
upgraded, you probably have a converter with a 2500 rpm stall speed. That
is NOT TO SAY THAT IT "LOCKS UP" because it never really does that. There
is always some slippage between engine speed and transmission input shaft
speed.
A true "lock up" converter is the same as a manual clutch (very little
slippage).
So, at 2100 rpm, your engine is turning faster than your transmission
input shaft, and some heating of the transmission fluid is occurring as a
result of that slippage. Engineers have to account for energy loss through
moving something by applying a force (work) or by heat loss.
Jim Hupy


> On Sun, Jan 27, 2019, 7:12 AM Matt Colie
> johnd01 wrote on Sun, 27 January 2019 04:55
>> Matt
>>
>>> I have the original Avion VIN A26000 with a GMC Firewall VIN of
>>> TZE064V10116 with a 455 and headers. Given that our drive wheels are
>>> about 15% larger than the car version the 3.07 would be like having a
> 2.60
>>> in the Toronado towing package. Not much of a towing package. So
> unless you
>>> are going to do a lot of flatland 80 mph driving in a very light
> coach a
>>> higher final drive ratio would be in order. A 3.53 would match the
> Toronado
>>> towing package . Will a higher final drive ratio take some of the
> strain
>>> off of the transmission and the rest of the drivetrain?
>>
>> * My coach is a very light 23. With the stock cam, it suffered at 60~65.
>> That was 21~2200 with the converter slip (it is not fully engaged at
> those*
>> *road speeds). *
>> Are you implying that you need more RPMs to get the torque converter to
>> lock up/not slip? Is there a lockup clutch in our converter?
>
> Yes John,
>
> That is exactly what I am saying and there was no lock-up version of
> torque converter for transmissions of this era. That did not come along
> until
> CAFE hit the scene. (Unless you were brave enough to try to drive a street
> car with a "Clutch-Flyt".
>
> Matt
>
> Quote:
>>> On Sat, Jan 26, 2019 at 9:48 AM James Hupy wrote:
>>>
>>> I have four extra gages on my 78 Royale 403. Vacuum, Tachometer,
>>> Transmission fluid temperature at the Ragusa finned aluminum pan, and
> final
>>> drive oil temperature. The Tachometer and Vacuum gage are mounted
> between
>>> the drivers side windshield and the horse collar that surrounds the
> dash.
>>> The oil gages are mounted where the ash tray used to be.
>>> I often run my 403 between 3000 and 3600 rpm. With the final
> drive
>>> and wheel and tire combinations that I run, that is between 62 and 75
> miles
>>> per hour. The 403 is a happy camper in that rpm range.
>>> The 455 will not be hurt a bit at those rpms either.
>>> If I am climbing long continuous grades, I will manually
> downshift and
>>> run the 403 at 4200 - 4500 rpm at 10 to 12 inches of mercury (
> throttles
>>> 1/2 way open) for long stretches. My original engine is still
> equipped with
>>> a quadrajet carb and Doug Thorley Coated headers, dual mufflers and a
> 2
>>> 3/4" tail pipe. It has over 130,000 miles and burns a quart of 20 -50
>>> Valvoline Dino oil in about 1500 miles. Last time I checked
> compression, it
>>> pumped over 150 psi across the board. I can't complain about that
>>> performance. The best modification I ever did was the 3:70 final drive
>>> gearing.
>>> Jim Hupy
>>>
>>> On Sat, Jan 26, 2019, 9:21 AM roy keen
>>>> I wouldn't be without a tack and I wouldn't run a 455 at or above
> 4000
>>> rpm
>>>> for any length of time especially in these western mountains with the
>>> pedal
>>>> to the metal. If you do and the motor wasn't modified for high rpm
> you
>>> may
>>>> be sorry you did.3000 is a lot safer.
>>>> --
>>>> Roy Keen
>>>> Minden,NV
>>>> 76 X Glenbrook
>>>>
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> https://apc01.safelinks.protection.outlook.com/?url=http%3A%2F%2Flist.gmcnet.org%2Fmailman%2Flistinfo%2Fgmclist_list.gmcnet.org&amp ;data=02%7C01%7C%7C7c770bac075c41cc84b208d6846e6627%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636842007023353764&sdata=oEOuMRm96pVz9yQi80zX ZFTJWwQuPaaHoPmj%2BJTAnBQ%3D&reserved=0
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> https://apc01.safelinks.protection.outlook.com/?url=http%3A%2F%2Flist.gmcnet.org%2Fmailman%2Flistinfo%2Fgmclist_list.gmcnet.org&amp ;data=02%7C01%7C%7C7c770bac075c41cc84b208d6846e6627%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636842007023353764&sdata=oEOuMRm96pVz9yQi80zX ZFTJWwQuPaaHoPmj%2BJTAnBQ%3D&reserved=0
>>
>>
>> --
>>
>> *John Phillips*
>> _______________________________________________
>> GMCnet mailing list
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>
>
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> https://apc01.safelinks.protection.outlook.com/?url=http%3A%2F%2Flist.gmcnet.org%2Fmailman%2Flistinfo%2Fgmclist_list.gmcnet.org&amp ;data=02%7C01%7C%7C7c770bac075c41cc84b208d6846e6627%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636842007023353764&sdata=oEOuMRm96pVz9yQi80zX ZFTJWwQuPaaHoPmj%2BJTAnBQ%3D&reserved=0
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Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340413 is a reply to message #340333] Sun, 27 January 2019 13:39 Go to previous messageGo to next message
bobby5832708 is currently offline  bobby5832708   United States
Messages: 237
Registered: November 2006
Location: Winter Springs FL
Karma: 3
Senior Member
"That is exactly what I am saying and there was no lock-up version of torque converter for transmissions of this era. That did not come along until CAFE hit the scene."


I seem to remember that Studebaker had a lockup torque converter decades ago, so a bit of Googling found this article which, in part, says:

Lockup clutches were used in some nonautomotive torque converters before World War II, but the first regular-production automotive application was the 1949 Packard Ultramatic Drive, which established a model for subsequent transmission designs. It was followed in fairly short order by the 1950 Studebaker Automatic Drive, which took a somewhat different approach to the same problem.


https://ateupwithmotor.com/terms-technology-definitions/split-torque-lockup-converters/?cookie-state-change=1548616977986

Correct me if I am wrong but 1949 and 1950 was waaaaaay before the CAFE age (law was enacted by Congress in 1975). For some reason I always insist on accurate data. If this article about Studebaker and Packard transmissions is inaccurate please let me know.

While I sometimes wish my GMC had a wider spread of gear ratios, I would think a lockup converter would be a benefit while cruising at light to moderate loads.


Bob Heller
2017 Winnebago 29VE
Winter Springs FL
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340417 is a reply to message #340413] Sun, 27 January 2019 14:32 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
If your nervous going over 3,000rpm, your off page in your experience with
engines.
There are times when I'm passing at hwy speeds when I will reve 4,500 for
short duration .
Back in the 90's there were lot of guys that knew engines and they inspired
me to move the gear ratio to 3.70.
Lock up converters we used in the 90's and did not really see any
worthwhile gains.
I and 15 other owners are running the 4.10 ratio with good results.
Opinions are good but my experience and feedback is hard to beat as we have
sold over 3,000 3.70 and get very good feedback.455 does better with 3.70
and have seen noticeable poor result with 3.55 and 3.42.
We're the only one that carry a 50,000 mile warranty .

On Sun, Jan 27, 2019 at 11:51 AM Bob Heller wrote:

> "That is exactly what I am saying and there was no lock-up version of
> torque converter for transmissions of this era. That did not come along
> until
> CAFE hit the scene."
>
>
> I seem to remember that Studebaker had a lockup torque converter decades
> ago, so a bit of Googling found this article which, in part, says:
>
> Lockup clutches were used in some nonautomotive torque converters before
> World War II, but the first regular-production automotive application was
> the
> 1949 Packard Ultramatic Drive, which established a model for subsequent
> transmission designs. It was followed in fairly short order by the 1950
> Studebaker Automatic Drive, which took a somewhat different approach to
> the same problem.
>
>
>
> https://ateupwithmotor.com/terms-technology-definitions/split-torque-lockup-converters/?cookie-state-change=1548616977986
>
> Correct me if I am wrong but 1949 and 1950 was waaaaaay before the CAFE
> age (law was enacted by Congress in 1975). For some reason I always insist
> on
> accurate data. If this article about Studebaker and Packard transmissions
> is inaccurate please let me know.
>
> While I sometimes wish my GMC had a wider spread of gear ratios, I would
> think a lockup converter would be a benefit while cruising at light to
> moderate loads.
> --
> Bob Heller
> 1974 X-Canyonlands 26ft
> Original 455 exc for timing chain,
> Rockwell intake, valve covers. 145k miles.
> Winter Springs FL
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340420 is a reply to message #340417] Sun, 27 January 2019 15:37 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Mac, to answer your lock up question, yes "BUT" it depends. Lockup means
several things depending upon whether it is a full mechanical lockup type,
or a hydraulic lockup type. The hydraulic type still slips a bit, and is
smoother in operation. Quieter, too.
Yes, but if it locks up below the usable torque curve, it might lug
the engine. Just what it does, there are no perfect torque converters, only
ones that work a few percentage points better than the others.
Jim Hupy

On Sun, Jan 27, 2019, 12:33 PM Jim Kanomata If your nervous going over 3,000rpm, your off page in your experience with[/color]
> engines.
> There are times when I'm passing at hwy speeds when I will reve 4,500 for
> short duration .
> Back in the 90's there were lot of guys that knew engines and they inspired
> me to move the gear ratio to 3.70.
> Lock up converters we used in the 90's and did not really see any
> worthwhile gains.
> I and 15 other owners are running the 4.10 ratio with good results.
> Opinions are good but my experience and feedback is hard to beat as we have
> sold over 3,000 3.70 and get very good feedback.455 does better with 3.70
> and have seen noticeable poor result with 3.55 and 3.42.
> We're the only one that carry a 50,000 mile warranty .
>
> On Sun, Jan 27, 2019 at 11:51 AM Bob Heller wrote:
>
>> "That is exactly what I am saying and there was no lock-up version of
>> torque converter for transmissions of this era. That did not come along
>> until
>> CAFE hit the scene."
>>
>>
>> I seem to remember that Studebaker had a lockup torque converter decades
>> ago, so a bit of Googling found this article which, in part, says:
>>
>> Lockup clutches were used in some nonautomotive torque converters before
>> World War II, but the first regular-production automotive application was
>> the
>> 1949 Packard Ultramatic Drive, which established a model for subsequent
>> transmission designs. It was followed in fairly short order by the 1950
>> Studebaker Automatic Drive, which took a somewhat different approach to
>> the same problem.
>>
>>
>>
>>
> https://ateupwithmotor.com/terms-technology-definitions/split-torque-lockup-converters/?cookie-state-change=1548616977986
>>
>> Correct me if I am wrong but 1949 and 1950 was waaaaaay before the CAFE
>> age (law was enacted by Congress in 1975). For some reason I always
> insist
>> on
>> accurate data. If this article about Studebaker and Packard transmissions
>> is inaccurate please let me know.
>>
>> While I sometimes wish my GMC had a wider spread of gear ratios, I would
>> think a lockup converter would be a benefit while cruising at light to
>> moderate loads.
>> --
>> Bob Heller
>> 1974 X-Canyonlands 26ft
>> Original 455 exc for timing chain,
>> Rockwell intake, valve covers. 145k miles.
>> Winter Springs FL
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340421 is a reply to message #340417] Sun, 27 January 2019 15:47 Go to previous messageGo to next message
Dolph Santorine is currently offline  Dolph Santorine   United States
Messages: 1236
Registered: April 2011
Location: Wheeling, WV
Karma: -41
Senior Member
We have a boat we play with on the Ohio River.

It’s an 8.1 liter (496 cubic Inch) big block Chevrolet

It’s perfectly happy making 4800 RPM (what boaters describe at WOT) for hours on end.

Of course, it does so while making 460 horsepower or so, and drinking an appropriate amount of fuel.

35 gallons per hour with a 100 gallon fuel tank.

Let’s just say I don’t run at that power setting often.

I remind other pilots that boaters have $100 hamburgers as well.

Dolph

DE AD0LF

Wheeling, West Virginia

1977 26’ ex-PalmBeach
Howell EFI & EBL, Reaction Arms, Sullybilt Bags, Manny Transmission

“The Aluminum and Fiberglass Mistress"

> On Jan 27, 2019, at 3:32 PM, Jim Kanomata wrote:
>
> If your nervous going over 3,000rpm, your off page in your experience with
> engines.
> There are times when I'm passing at hwy speeds when I will reve 4,500 for
> short duration .
> Back in the 90's there were lot of guys that knew engines and they inspired
> me to move the gear ratio to 3.70.
> Lock up converters we used in the 90's and did not really see any
> worthwhile gains.
> I and 15 other owners are running the 4.10 ratio with good results.
> Opinions are good but my experience and feedback is hard to beat as we have
> sold over 3,000 3.70 and get very good feedback.455 does better with 3.70
> and have seen noticeable poor result with 3.55 and 3.42.
> We're the only one that carry a 50,000 mile warranty .
>
> On Sun, Jan 27, 2019 at 11:51 AM Bob Heller wrote:
>
>> "That is exactly what I am saying and there was no lock-up version of
>> torque converter for transmissions of this era. That did not come along
>> until
>> CAFE hit the scene."
>>
>>
>> I seem to remember that Studebaker had a lockup torque converter decades
>> ago, so a bit of Googling found this article which, in part, says:
>>
>> Lockup clutches were used in some nonautomotive torque converters before
>> World War II, but the first regular-production automotive application was
>> the
>> 1949 Packard Ultramatic Drive, which established a model for subsequent
>> transmission designs. It was followed in fairly short order by the 1950
>> Studebaker Automatic Drive, which took a somewhat different approach to
>> the same problem.
>>
>>
>>
>> https://ateupwithmotor.com/terms-technology-definitions/split-torque-lockup-converters/?cookie-state-change=1548616977986
>>
>> Correct me if I am wrong but 1949 and 1950 was waaaaaay before the CAFE
>> age (law was enacted by Congress in 1975). For some reason I always insist
>> on
>> accurate data. If this article about Studebaker and Packard transmissions
>> is inaccurate please let me know.
>>
>> While I sometimes wish my GMC had a wider spread of gear ratios, I would
>> think a lockup converter would be a benefit while cruising at light to
>> moderate loads.
>> --
>> Bob Heller
>> 1974 X-Canyonlands 26ft
>> Original 455 exc for timing chain,
>> Rockwell intake, valve covers. 145k miles.
>> Winter Springs FL
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340429 is a reply to message #340333] Sun, 27 January 2019 18:45 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
Messages: 1085
Registered: October 2008
Location: Colfax, CA
Karma: 11
Senior Member
BobDunahugh wrote on Thu, 24 January 2019 20:40
( GRIN ) When someone says that any RPM's over 3300 RPM's. will just burn the engine up. Due to high piston speeds. That is absolutely, positively not true. Bob Dunahugh 78 Royale
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I agree with Bob. I lost my governer gear on a rolling rally. We could not pull the governor because the pin had worked out, hitting the case and locking it in. (Who knows why, because that roll pin is tight!)

Anyway, I drove about 120 miles home in low gear. I never used to run my 455 over 3200 and never even 3000 for long times. All I can say is after a while, 4000 RPMs doesn't sound so bad.

After you fix the transmission, you think, "This is sure a nice quiet coach."


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340464 is a reply to message #340405] Mon, 28 January 2019 19:30 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
Messages: 354
Registered: July 2017
Location: Sacrameot
Karma: -1
Senior Member
James,
So from about 2000 to 3000 RPM the slippage reduces but never locks up. The
more slippage in the converter the more heat is generated which does
require more fuel burn. The extra fuel burn must not be very much or we
would be seeing people talking about upgrading to a lockup converter to
save fuel.
Correct me if I am wrong but I figured my front wheels at the present tire
pressure have an effective circumference of 84 inches. 2500 engine RPM
/3.07 final drive gives a wheel RPM of 814. 814 * 84 /12 inches per foot *
60 minutes per hour / 5280 feet per mile comes out to 64.8 MPH with 0 slip.
Comes out to 25.9 miles/1000RPM.

I have felt that running in the low 2000sands would lengthen engine life as
long as the engine was not working hard.

My car rarely gets to 2500 RPM.

On Sun, Jan 27, 2019 at 7:44 AM James Hupy wrote:

> Depending upon whether or not your torque converter is original or has been
> upgraded, you probably have a converter with a 2500 rpm stall speed. That
> is NOT TO SAY THAT IT "LOCKS UP" because it never really does that. There
> is always some slippage between engine speed and transmission input shaft
> speed.
> A true "lock up" converter is the same as a manual clutch (very little
> slippage).
> So, at 2100 rpm, your engine is turning faster than your transmission
> input shaft, and some heating of the transmission fluid is occurring as a
> result of that slippage. Engineers have to account for energy loss through
> moving something by applying a force (work) or by heat loss.
> Jim Hupy
>
>
> On Sun, Jan 27, 2019, 7:12 AM Matt Colie
>> johnd01 wrote on Sun, 27 January 2019 04:55
>>> Matt
>>>
>>>> I have the original Avion VIN A26000 with a GMC Firewall VIN of
>>>> TZE064V10116 with a 455 and headers. Given that our drive wheels
> are
>>>> about 15% larger than the car version the 3.07 would be like having
> a
>> 2.60
>>>> in the Toronado towing package. Not much of a towing package. So
>> unless you
>>>> are going to do a lot of flatland 80 mph driving in a very light
>> coach a
>>>> higher final drive ratio would be in order. A 3.53 would match the
>> Toronado
>>>> towing package . Will a higher final drive ratio take some of the
>> strain
>>>> off of the transmission and the rest of the drivetrain?
>>>
>>> * My coach is a very light 23. With the stock cam, it suffered at
> 60~65.
>>> That was 21~2200 with the converter slip (it is not fully engaged at
>> those*
>>> *road speeds). *
>>> Are you implying that you need more RPMs to get the torque converter to
>>> lock up/not slip? Is there a lockup clutch in our converter?
>>
>> Yes John,
>>
>> That is exactly what I am saying and there was no lock-up version of
>> torque converter for transmissions of this era. That did not come along
>> until
>> CAFE hit the scene. (Unless you were brave enough to try to drive a
> street
>> car with a "Clutch-Flyt".
>>
>> Matt
>>
>> Quote:
>>> On Sat, Jan 26, 2019 at 9:48 AM James Hupy wrote:
>>>
>>>> I have four extra gages on my 78 Royale 403. Vacuum, Tachometer,
>>>> Transmission fluid temperature at the Ragusa finned aluminum pan,
> and
>> final
>>>> drive oil temperature. The Tachometer and Vacuum gage are mounted
>> between
>>>> the drivers side windshield and the horse collar that surrounds the
>> dash.
>>>> The oil gages are mounted where the ash tray used to be.
>>>> I often run my 403 between 3000 and 3600 rpm. With the final
>> drive
>>>> and wheel and tire combinations that I run, that is between 62 and
> 75
>> miles
>>>> per hour. The 403 is a happy camper in that rpm range.
>>>> The 455 will not be hurt a bit at those rpms either.
>>>> If I am climbing long continuous grades, I will manually
>> downshift and
>>>> run the 403 at 4200 - 4500 rpm at 10 to 12 inches of mercury (
>> throttles
>>>> 1/2 way open) for long stretches. My original engine is still
>> equipped with
>>>> a quadrajet carb and Doug Thorley Coated headers, dual mufflers and
> a
>> 2
>>>> 3/4" tail pipe. It has over 130,000 miles and burns a quart of 20
> -50
>>>> Valvoline Dino oil in about 1500 miles. Last time I checked
>> compression, it
>>>> pumped over 150 psi across the board. I can't complain about that
>>>> performance. The best modification I ever did was the 3:70 final
> drive
>>>> gearing.
>>>> Jim Hupy
>>>>
>>>> On Sat, Jan 26, 2019, 9:21 AM roy keen
>>>> > I wouldn't be without a tack and I wouldn't run a 455 at or above
>> 4000
>>>> rpm
>>>> > for any length of time especially in these western mountains with
> the
>>>> pedal
>>>> > to the metal. If you do and the motor wasn't modified for high rpm
>> you
>>>> may
>>>> > be sorry you did.3000 is a lot safer.
>>>> > --
>>>> > Roy Keen
>>>> > Minden,NV
>>>> > 76 X Glenbrook
>>>> >
>>>> > _______________________________________________
>>>> > GMCnet mailing list
>>>> > Unsubscribe or Change List Options:
>>>> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>> >
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>>
>>>
>>>
>>> --
>>>
>>> *John Phillips*
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>>
>> --
>> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
>> Electronically Controlled Quiet Engine Cooling Fan
>> OE Rear Drum Brakes with Applied Control Arms
>> SE Michigan - Twixt A2 and Detroit
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--

*John Phillips*
_______________________________________________
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Unsubscribe or Change List Options:
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Tid Bits. Should we be concerned about over reving our Olds engines. [message #340465 is a reply to message #340464] Mon, 28 January 2019 21:27 Go to previous messageGo to previous message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
The REAL KEY to whether or not you are doing damage to your engine at low
rpms is load / throttle opening. If you are running at 15 inches of mercury
at 1500 rpm, you are not likely to do much damage. However, if you are
running with 4 inches of mercury, you will be lugging the heck out of your
engine.
Jim Hupy
Salem, Or

On Mon, Jan 28, 2019, 5:27 PM John Phillips James,[/color]
> So from about 2000 to 3000 RPM the slippage reduces but never locks up. The
> more slippage in the converter the more heat is generated which does
> require more fuel burn. The extra fuel burn must not be very much or we
> would be seeing people talking about upgrading to a lockup converter to
> save fuel.
> Correct me if I am wrong but I figured my front wheels at the present tire
> pressure have an effective circumference of 84 inches. 2500 engine RPM
> /3.07 final drive gives a wheel RPM of 814. 814 * 84 /12 inches per foot *
> 60 minutes per hour / 5280 feet per mile comes out to 64.8 MPH with 0 slip.
> Comes out to 25.9 miles/1000RPM.
>
> I have felt that running in the low 2000sands would lengthen engine life as
> long as the engine was not working hard.
>
> My car rarely gets to 2500 RPM.
>
> On Sun, Jan 27, 2019 at 7:44 AM James Hupy wrote:
>
>> Depending upon whether or not your torque converter is original or has
> been
>> upgraded, you probably have a converter with a 2500 rpm stall speed. That
>> is NOT TO SAY THAT IT "LOCKS UP" because it never really does that. There
>> is always some slippage between engine speed and transmission input shaft
>> speed.
>> A true "lock up" converter is the same as a manual clutch (very
> little
>> slippage).
>> So, at 2100 rpm, your engine is turning faster than your
> transmission
>> input shaft, and some heating of the transmission fluid is occurring as a
>> result of that slippage. Engineers have to account for energy loss
> through
>> moving something by applying a force (work) or by heat loss.
>> Jim Hupy
>>
>>
>> On Sun, Jan 27, 2019, 7:12 AM Matt Colie >
>>> johnd01 wrote on Sun, 27 January 2019 04:55
>>>> Matt
>>>>
>>>> > I have the original Avion VIN A26000 with a GMC Firewall VIN of
>>>> > TZE064V10116 with a 455 and headers. Given that our drive wheels
>> are
>>>> > about 15% larger than the car version the 3.07 would be like
> having
>> a
>>> 2.60
>>>> > in the Toronado towing package. Not much of a towing package. So
>>> unless you
>>>> > are going to do a lot of flatland 80 mph driving in a very light
>>> coach a
>>>> > higher final drive ratio would be in order. A 3.53 would match the
>>> Toronado
>>>> > towing package . Will a higher final drive ratio take some of the
>>> strain
>>>> > off of the transmission and the rest of the drivetrain?
>>>>
>>>> * My coach is a very light 23. With the stock cam, it suffered at
>> 60~65.
>>>> That was 21~2200 with the converter slip (it is not fully engaged at
>>> those*
>>>> *road speeds). *
>>>> Are you implying that you need more RPMs to get the torque converter
> to
>>>> lock up/not slip? Is there a lockup clutch in our converter?
>>>
>>> Yes John,
>>>
>>> That is exactly what I am saying and there was no lock-up version of
>>> torque converter for transmissions of this era. That did not come
> along
>>> until
>>> CAFE hit the scene. (Unless you were brave enough to try to drive a
>> street
>>> car with a "Clutch-Flyt".
>>>
>>> Matt
>>>
>>> Quote:
>>>> On Sat, Jan 26, 2019 at 9:48 AM James Hupy wrote:
>>>>
>>>> > I have four extra gages on my 78 Royale 403. Vacuum, Tachometer,
>>>> > Transmission fluid temperature at the Ragusa finned aluminum pan,
>> and
>>> final
>>>> > drive oil temperature. The Tachometer and Vacuum gage are mounted
>>> between
>>>> > the drivers side windshield and the horse collar that surrounds
> the
>>> dash.
>>>> > The oil gages are mounted where the ash tray used to be.
>>>> > I often run my 403 between 3000 and 3600 rpm. With the final
>>> drive
>>>> > and wheel and tire combinations that I run, that is between 62 and
>> 75
>>> miles
>>>> > per hour. The 403 is a happy camper in that rpm range.
>>>> > The 455 will not be hurt a bit at those rpms either.
>>>> > If I am climbing long continuous grades, I will manually
>>> downshift and
>>>> > run the 403 at 4200 - 4500 rpm at 10 to 12 inches of mercury (
>>> throttles
>>>> > 1/2 way open) for long stretches. My original engine is still
>>> equipped with
>>>> > a quadrajet carb and Doug Thorley Coated headers, dual mufflers
> and
>> a
>>> 2
>>>> > 3/4" tail pipe. It has over 130,000 miles and burns a quart of 20
>> -50
>>>> > Valvoline Dino oil in about 1500 miles. Last time I checked
>>> compression, it
>>>> > pumped over 150 psi across the board. I can't complain about that
>>>> > performance. The best modification I ever did was the 3:70 final
>> drive
>>>> > gearing.
>>>> > Jim Hupy
>>>> >
>>>> > On Sat, Jan 26, 2019, 9:21 AM roy keen
>>>> >> I wouldn't be without a tack and I wouldn't run a 455 at or above
>>> 4000
>>>> > rpm
>>>> >> for any length of time especially in these western mountains with
>> the
>>>> > pedal
>>>> >> to the metal. If you do and the motor wasn't modified for high
> rpm
>>> you
>>>> > may
>>>> >> be sorry you did.3000 is a lot safer.
>>>> >> --
>>>> >> Roy Keen
>>>> >> Minden,NV
>>>> >> 76 X Glenbrook
>>>> >>
>>>> >> _______________________________________________
>>>> >> GMCnet mailing list
>>>> >> Unsubscribe or Change List Options:
>>>> >> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>> >>
>>>> > _______________________________________________
>>>> > GMCnet mailing list
>>>> > Unsubscribe or Change List Options:
>>>> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>> >
>>>>
>>>>
>>>> --
>>>>
>>>> *John Phillips*
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>>>
>>> --
>>> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
>>> Electronically Controlled Quiet Engine Cooling Fan
>>> OE Rear Drum Brakes with Applied Control Arms
>>> SE Michigan - Twixt A2 and Detroit
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
> --
>
> *John Phillips*
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
_______________________________________________
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Unsubscribe or Change List Options:
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