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[GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326856] Thu, 07 December 2017 14:56 Go to next message
BobDunahugh is currently offline  BobDunahugh   United States
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We were with some GMC people last weekend. And it was mentioned that one person wouldn't leave till the engine was to full operating temps. It's true that there is less wear at full engine temp. But that temp is reached much faster while driving. As there is more fuel burned while on the move. Thus the engine has more BTU's used up in the process. The cylinder walls, an pistons have had 2000 degrees put to them. As to the oil getting moved around. In one minute. The oil filter, and all oil passages were full to start with. The oil pump has delivered about another 6 qts to get every moving part lubed. The engine has had the crank rotate around 700 times in that minute.. I'm sure there are lots of thoughts on this one. I use the one minute idea. One of the things that help these engines last so long. ( As long as there maintained properly.) Is you don't use them for short trips. Thus less cold starts per mile. As a interesting side note. The 403 piston travels less feet per mile then a 455. So does a 403 piston/rings last longer? Bob Dunahugh 78 Royale.
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Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326873 is a reply to message #326856] Thu, 07 December 2017 18:39 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Bob,
I am going to respond to these inline and based on log time engine test lab experience.
BobDunahugh wrote on Thu, 07 December 2017 15:56
We were with some GMC people last weekend. And it was mentioned that one person wouldn't leave till the engine was to full operating temps.
=> There nothing good that happens to in an idling engine.

It's true that there is less wear at full engine temp. But that temp is reached much faster while driving.
=> In my durability dynos, the rule was always to stay under 1500 and 15"Map (~14" vacuum) until lube oil it 100°F. This never took very long.

As there is more fuel burned while on the move. Thus the engine has more BTU's used up in the process. The cylinder walls, an pistons have had 2000 degrees put to them. As to the oil getting moved around. In one minute. The oil filter, and all oil passages were full to start with.
=> Whether the oil passages were full or not is an open issue and depends on the engine and how long it had been sitting. It can take 30 seconds to a minute for all the places that get oil to actually get any after a long sit. That 100°F is never very far behind.

The oil pump has delivered about another 6 qts to get every moving part lubed. The engine has had the crank rotate around 700 times in that minute.. I'm sure there are lots of thoughts on this one. I use the one minute idea. One of the things that help these engines last so long. ( As long as there maintained properly.) Is you don't use them for short trips. Thus less cold starts per mile.
=> You are very correct about cold starts being tough on every thing. This is why capital engines (like it ships) are kept hot with heating systems when not actually running.

As a interesting side note. The 403 piston travels less feet per mile then a 455. So does a 403 piston/rings last longer?
=> Hang on tight, here we go....
Piston travel is a definite issue, but it takes a back seat to BMEP (Brake Mean Effective Pressure). BMEP is what makes the force to push the piston so then engine makes torque. More BMEP is more load on the rings.
The larger piston 4.351 (403) vs 4.126 (455) would make for lower BMEP at the same torque,
BBUUTT
The shorter stroke 3.385 vs 4.250 means it takes more BMEP for the same torque output.

Bob Dunahugh 78 Royale.


To move the coach down the road will take XX horsepower. HP = RPM X Torque / 5252
So, if you put a high numerical final drive on a 403 so it does not need as much BMEP to get down the road, you can unload the rings and probably before you get to the same piston travel per mile, you may beat break even. It is a given that spinning the short stoke engine will be more to its liking. (This is exactly why I am such a great proponent of 3.70s in for 403 coaches.)

Now, did that clear anything up for anybody?
If you can form a question, I will do my best to provide an answer that you can understand.

Matt


Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
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Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326875 is a reply to message #326856] Thu, 07 December 2017 20:11 Go to previous messageGo to next message
cbryan   United States
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Matt,

With reference to the idling before setting off issue, and the piston feet per minute, I am assuming that the higher compression, the higher BMEP, all things else being equal, the greater ring and cylinder wall wear?

That, if true, might mean that the new Mazdas with their "Skyactiv" technology with 14 to 1 compression will wear out sooner. There is the factor as well, that I have read that engines last far longer with fuel injection due to the excessively rich condition with carbs when cold. Like, about twice as much mileage on a engine before it is worn out.

Looking at the factor that friction increases as the square of RPM, it would also make sense that operating at low RPM would add engine longevity as well, assuming that the friction increase at least is partly located in the piston-cylinder interface and will result in increased wear. Hard to see where if there is no friction, that any wear at all will occur.

Not anything I have measured, to be sure. I have been an advocate for setting out immediately with a cold engine, not asking more than the minimum until there's an indication on the temperature gauge, or on my Toyota, when the green "cold engine" light goes out. I've never worn out an engine in my life. Oops, those chain saws I lunched due to using on-hand outboard oil in the fuel mix, I wore them out. How easy it is to believe I am smarter than the company engineers. And to find out the hard way they were right. It took two chain saws before the light came on. You have to use 2-stroke oil rated for "air cooled engines", at least my experience has bought me that knowledge.

Thanks for sharing your hard-won knowledge with us. It's really interesting.

Carey



Carey from Ennis, Texas 78 Royale, 500 Cadillac, Rance Baxter EFI.
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326877 is a reply to message #326875] Thu, 07 December 2017 22:01 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Your not going to wear out an engine, but you will start consuming oil.
The new synthetic oils will protect the warm engine even at higher rpm

Sent from my iPhone

> On Dec 7, 2017, at 6:11 PM, Carey Bryan wrote:
>
> Matt,
>
> With reference to the idling before setting off issue, and the piston feet per minute, I am assuming that the higher compression, the higher BMEP, all
> things else being equal, the greater ring and cylinder wall wear?
>
> That, if true, might mean that the new Mazdas with their "Skyactiv" technology with 14 to 1 compression will wear out sooner. There is the factor as
> well, that I have read that engines last far longer with fuel injection due to the excessively rich condition with carbs when cold. Like, about twice
> as much mileage on a engine before it is worn out.
>
> Looking at the factor that friction increases as the square of RPM, it would also make sense that operating at low RPM would add engine longevity as
> well, assuming that the friction increase at least is partly located in the piston-cylinder interface and will result in increased wear. Hard to see
> where if there is no friction, that any wear at all will occur.
>
> Not anything I have measured, to be sure. I have been an advocate for setting out immediately with a cold engine, not asking more than the minimum
> until there's an indication on the temperature gauge, or on my Toyota, when the green "cold engine" light goes out. I've never worn out an engine in
> my life. Oops, those chain saws I lunched due to using on-hand outboard oil in the fuel mix, I wore them out. How easy it is to believe I am smarter
> than the company engineers. And to find out the hard way they were right. It took two chain saws before the light came on. You have to use 2-stroke
> oil rated for "air cooled engines", at least my experience has bought me that knowledge.
>
> Thanks for sharing your hard-won knowledge with us. It's really interesting.
>
> Carey
>
>
> --
> Carey from Ennis, Texas
> 78 Royale, 500 Cadillac, Rance Baxter EFI.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326900 is a reply to message #326875] Fri, 08 December 2017 10:06 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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cbryan wrote on Thu, 07 December 2017 21:11
Matt,

With reference to the idling before setting off issue, and the piston feet per minute, I am assuming that the higher compression, the higher BMEP, all things else being equal, the greater ring and cylinder wall wear?

That, if true, might mean that the new Mazdas with their "Skyactiv" technology with 14 to 1 compression will wear out sooner. There is the factor as well, that I have read that engines last far longer with fuel injection due to the excessively rich condition with carbs when cold. Like, about twice as much mileage on a engine before it is worn out.

Looking at the factor that friction increases as the square of RPM, it would also make sense that operating at low RPM would add engine longevity as well, assuming that the friction increase at least is partly located in the piston-cylinder interface and will result in increased wear. Hard to see where if there is no friction, that any wear at all will occur.

Not anything I have measured, to be sure. I have been an advocate for setting out immediately with a cold engine, not asking more than the minimum until there's an indication on the temperature gauge, or on my Toyota, when the green "cold engine" light goes out. I've never worn out an engine in my life. Oops, those chain saws I lunched due to using on-hand outboard oil in the fuel mix, I wore them out. How easy it is to believe I am smarter than the company engineers. And to find out the hard way they were right. It took two chain saws before the light came on. You have to use 2-stroke oil rated for "air cooled engines", at least my experience has bought me that knowledge.

Thanks for sharing your hard-won knowledge with us. It's really interesting.

Carey

Carey,

Unfortunately, higher compression does not make for a universally higher BMEP. Compression ratio is a static number and BMEP is completely dynamic. There is a lot that goes into BMEP, but all BMEP does come out as torque.

Skyactiv is a Mazda label for lots of new stuff. It covers a diesel, a transmission and a direct injection SI engine. The claimed 14:1 may be real, but for it to be an SI (Spark Ignition) engine - even while direct injected, it needs to control the manifold pressure. Direct injection for SI engines is not new. The DB605 used in the BF109 was a direct injected engine.

Just in my working lifetime, engine building technology has made amazing changes everywhere. One of the biggest has been the capability of manufactures to make round cylinder bores. The round bore allows a low tension ring. The low tension ring allows the use of both a better oil control hone finish on the bore wall and a better wearing alloy for the compression rings. This all adds up pretty fast.

There is a variety of engine dynomometer that is just a big DC machine on bearings. The reason I said machine is because they are capable of both motoring and absorbing. Very early in every engine program, we would do a motoring curve. With the intake at WOT, spin the engine at continually increasing speed to see that A: Everything works as it should (disasters are less exciting with cold engine) and B: Actually measure the internal friction. The observed friction increase was typically very linear until higher speeds when the pumping loss for the charge air would get in the way. If you happen to notice, the more recent engines pay a lot of attention to the intake and exhaust design. This is not just your imagination. There is a lot that can be done there. And with the EPA pushing so many things, smaller engines doing more work can be an advantage to many things.

The wet fuel issue was first noticed when passcar engines were converted to gas fuel - either LP or natural - and it is real, but they do still have wear issues. Those engine still do not live forever, but an industrial 455 on natural gas will come pretty close. Those were shipped with hard exhaust seats and forged cranks.

Let's not get into the problems of crankcase scavenged 2-stokes. They are a breed all to there own. You are not nearly the only person to discover that the wrong lube oil is a bad idea.

It is my honor to share as much as I can. I get to where I am with the help and guidance of many good people.

Matt


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
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326966 is a reply to message #326856] Sun, 10 December 2017 07:01 Go to previous messageGo to next message
Chris Tyler is currently offline  Chris Tyler   United States
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Observations about wear from compression ratio and stroke:

If static compression were an issue, diesel engines wouldnt last very long.

I don't know that the marginal increase in stroke itself [ie piston travel]is a significant factor in ring wear. What I have observed though is that longer stroke engines, particularly with shorter or less than optimim rod length:stroke ratio seem to have much worse bore wear, probably from the side load. The bores almost always seem to be out of round

May be less of an issue with lower RPM/load and higher nickel blocks.


76 Glenbrook
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326969 is a reply to message #326856] Sun, 10 December 2017 09:21 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Water. Water is the issue during a long cold and lazy warm up. More than a gallon is produced for each gallon of fuel burn. Thankfully most exits via exhaust but the rest ends up in the oil until it boils off. After about 60 Secs (and bags have reached auto level) I drive off gently to minimize idling. Then drive normally but not aggressively til normal temp. On a sliding scale I would adjust times with temp drop. Might be 2 mins below zero and driving more gently at first as well. But road load is your friend in the anti watering war. Also the dash heat will work much sooner and forward progress beats 0 MPG any day.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326970 is a reply to message #326969] Sun, 10 December 2017 10:04 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Ring reversal under combustion pressures wears rings, cylinder bores and
piston ring lands and grooves about as much as anything else. Compound that
with dirty intake air fuel mixture, and not enough lubrication at the top
of the bore and you can see why the top of the bores wear more than the
bottom does. Further compound that issue by doing it when the engine oils
and coolant is not at operating temperature and you have your answer to why
cold engines wear more quickly than warmed up ones do. Many more factors to
consider here, but that's enough to keep this conversation going for now.
Jim Hupy
Salem, Or (currently at a GMC CASCADER rally at Westport, Washington. It is
a balmy 39 degrees farenheit and the sun is just peeking over the clear
cloudless horizon. Travel home today, where it currently is 28 degrees.)

On Dec 10, 2017 7:22 AM, "John R. Lebetski" wrote:

> Water. Water is the issue during a long cold and lazy warm up. More than a
> gallon is produced for each gallon of fuel burn. Thankfully most exits via
> exhaust but the rest ends up in the oil until it boils off. After about 60
> Secs (and bags have reached auto level) I drive off gently to minimize
> idling. Then drive normally but not aggressively til normal temp. On a
> sliding scale I would adjust times with temp drop. Might be 2 mins below
> zero
> and driving more gently at first as well. But road load is your friend in
> the anti watering war. Also the dash heat will work much sooner and forward
> progress beats 0 MPG any day.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
>
>
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Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326981 is a reply to message #326856] Sun, 10 December 2017 15:31 Go to previous messageGo to next message
Johnny Bridges is currently offline  Johnny Bridges   United States
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With flat motors, we said as soon as it would take full throttle without stumbling, it's warm enough to fly. By the time you do your runup, and cycle the prop, it'll be that warn. Same with the gmc, by the time you check everything after you crank it and get out on the streert, it's ready to ride, and uless you live at an exit, the GMC should be warm enough for freeway speeds.

--johnny


76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. "I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326985 is a reply to message #326856] Sun, 10 December 2017 17:56 Go to previous messageGo to next message
Ray Erspamer is currently offline  Ray Erspamer   United States
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Well....my brain turned to OATMEAL on this thread. Happy someone understands it.

Ray Erspamer 78 GMC Royale 414-484-9431
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326988 is a reply to message #326985] Sun, 10 December 2017 20:01 Go to previous messageGo to next message
Kingsley Coach is currently offline  Kingsley Coach   United States
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Ah, Man...as my guru John Muir said... " Fire it up and roll one, that's
how much warm up it needs !"

Peace Brother...

https://en.wikipedia.org/wiki/John_Muir_(engineer)

On Sun, Dec 10, 2017 at 7:56 PM, Ray Erspamer wrote:

> Well....my brain turned to OATMEAL on this thread. Happy someone
> understands it.
> --
> Ray Erspamer
> 78 GMC Royale
> 414-484-9431
>
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1977 Eleganza II 26-3
Antigonish, NS

Life is too short to hold a grudge; slash some tires and call it even !
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Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326993 is a reply to message #326856] Sun, 10 December 2017 23:04 Go to previous messageGo to next message
cbryan   United States
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Matt,

Thanks for your response with regard to motoring (running by electric motor with no fuel to the engine), a gasoline automobile engine when it was cold to graph the friction to rpm factor. I was surprised to read that your experience that the friction was pretty linear. I have since looked on the net and found some engineers at MIT have done the same thing, and their graphs, both predicted and measured look much like a linear relationship with some mild upward curve until as you say pumping losses begin to rise quickly. I have also glanced at equations of total engine friction vs RPM and one factor does increase as the square of RPM, but it is only one of a number of factors, the others being linear, if I understand them. Real world experience as you have related to us is helpful. (I imagine you ran with throttle plates fully open?)

With reference to the comment by Jim K on never wearing an engine out but seeing them increase oil consumption. I have never worn an engine to the point that the oil consumption was over, say, 1000 miles per quart. Most were negligible. I don't like to burn oil. Not too religious about oil changing, but I do avoid high RPM if I can.

Got a story Chris, about a friend who bought a diesel over the road truck new some years ago. It used a 3208 Caterpillar engine. In the first three months, he cracked a piston. Took it back to the Cat dealer, and when he picked it up, he asked the dealer what he did. "Just replaced the piston." He said, "What, no boring, no honing, just replaced the piston and rings?", Dealer says, "Yes, you will be OK." He ran the truck 750,000 miles and sold it and it ran years afterward. So, even with diesel fuel having some lubricating properties, the high compression is no problem for it, as you say.

One more story. I have gone to China 12 times now, and remember the Volkswagen Santana taxis all over the place. Gasoline, manual shift. The first few times I rode in them, I had to bite my tongue. They short shifted them, first to about 7 mph, second to 12,skip to fourth and lug the engine up a ways and to fifth, to get the rest of the way to 35 mph. I confidently predicted to myself that they were beating the bearings out of the engine. I looked at the odometer, 270,000 kilometers. Other taxis were achieving like mileages. Got back from China last month, and on that trip they were doing the same thing. I figured more economy due to two factors, lower friction, and the largest factor, smaller pumping losses due to greater throttle opening. Fuel injected, ordinary cars otherwise. Four door midsize sedans.

Carey








Carey from Ennis, Texas 78 Royale, 500 Cadillac, Rance Baxter EFI.
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326994 is a reply to message #326985] Mon, 11 December 2017 07:54 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Ray Erspamer wrote on Sun, 10 December 2017 18:56
Well....my brain turned to OATMEAL on this thread. Happy someone understands it.

Ray,

I am glad that you made this statement....

What you need to know is:
Nothing good happens at idle.
Never abuse a cold engine.

So, if the engine is stable enough to pull the vehicle, go.
If the temperature gauge is off the pin, run it.

It that not easier to grasp?

Matt


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
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #326995 is a reply to message #326994] Mon, 11 December 2017 08:08 Go to previous messageGo to next message
Ray Erspamer is currently offline  Ray Erspamer   United States
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Absolutely! Thank you. My techniques has been.....start it up, let it fast idle for a minute....and if the choke is set right it will either go or cough....if it coughs I let it warm up a bit more. If it pulls steady I drive it without abusing it.

Ray Erspamer 78 GMC Royale 414-484-9431

[Updated on: Mon, 11 December 2017 08:12]

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Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #327001 is a reply to message #326995] Mon, 11 December 2017 10:18 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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It is all about setting the choke.
Too much is not good either.
Ray, I feel your procedure is good as it is better on the lean side during
choke mode.

On Mon, Dec 11, 2017 at 6:08 AM, Ray Erspamer wrote:

> Absolutely! Thank you. My techniques has been.....start it up, let it
> fast idle for a minute....and if the choke is set right it will either go
> and
> cough....if it coughs I let it warm up a bit more. If it pulls steady I
> drive it without abusing it.
> --
> Ray Erspamer
> 78 GMC Royale
> 414-484-9431
>
> _______________________________________________
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--
Jim Kanomata
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www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #327009 is a reply to message #326856] Mon, 11 December 2017 11:04 Go to previous messageGo to next message
tgeiger is currently offline  tgeiger   United States
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I like reading thru this but I'm in the se boat, half of it is over my head. I'm kinda thinking the conclusion was let it warm up a couple minutes and drive on?? Not sure, but anyhow I wanted to mention for me after the crossover ports were blocked, this has been a bear to keep running after a cold start. When it gets 20 or 30 here in KC iif I have to drive her somewhere then she not too happy about it unless she gets 5 or 10 on the warm up. Am I missing something on that mod?

Tom
76 Eleganza 2
KCMO
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #327010 is a reply to message #327009] Mon, 11 December 2017 11:14 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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CallTom,
So you have an electric choke?
If you did not you neglected to make a required change.
Call me and I will advise you as to what you need to do.
There are always somethings that are not pointed out as it is assumed
people should know. I for one tend to over explain as I never know that
they do not know.


On Mon, Dec 11, 2017 at 9:04 AM, tom geiger wrote:

> I like reading thru this but I'm in the se boat, half of it is over my
> head. I'm kinda thinking the conclusion was let it warm up a couple minutes
> and drive on?? Not sure, but anyhow I wanted to mention for me after the
> crossover ports were blocked, this has been a bear to keep running after a
> cold start. When it gets 20 or 30 here in KC iif I have to drive her
> somewhere then she not too happy about it unless she gets 5 or 10 on the
> warm up.
> Am I missing something on that mod?
>
> Tom
> 76 Eleganza 2
> KCMO
>
> _______________________________________________
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Jim Kanomata
Applied/GMC
jimk-AT-appliedairfilters-DOT-com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #327014 is a reply to message #326856] Mon, 11 December 2017 12:35 Go to previous messageGo to next message
tgeiger is currently offline  tgeiger   United States
Messages: 241
Registered: February 2006
Location: kansas city
Karma: 0
Senior Member
Hey Jim, I do have a electric choke. I will give you a call. No worries on over explaining with me, not at ground zero but still hovering below the tree line.
Re: [GMCnet] 2 interesting topics. Warming up your engine before leaving the drive. Piston travel. [message #327050 is a reply to message #327009] Tue, 12 December 2017 11:54 Go to previous message
Matt Colie is currently offline  Matt Colie   United States
Messages: 6474
Registered: March 2007
Location: S.E. Michigan
Karma: 32
Senior Member
tgeiger wrote on Mon, 11 December 2017 12:04
I like reading thru this but I'm in the se boat, half of it is over my head. I'm kinda thinking the conclusion was let it warm up a couple minutes and drive on?? Not sure, but anyhow I wanted to mention for me after the crossover ports were blocked, this has been a bear to keep running after a cold start. When it gets 20 or 30 here in KC iif I have to drive her somewhere then she not too happy about it unless she gets 5 or 10 on the warm up. Am I missing something on that mod?

Tom
76 Eleganza 2
KCMO

Tom,

By next winter, I will know more, but I suspect that you are partly correct. My experience is not with an Olds 455, but I have run more than a few V-8s that did not have the heat riser in the intake manifold. They are always "cold blooded". One of the things that I know you will need is the thing called a warm air stove and damper in the intake horn. While these were mostly unneeded, with the cold intake, they may now be needed.

There is another thing that is sort of hidden. If you are running the choke element off the alternator output, you may need to look up and get the temperature switch so it does not open too soon.

As said, ask me again next year.

Matt


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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