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[GMCnet] Two SandJ engine report [message #272586] Tue, 24 February 2015 21:20 Go to next message
glwgmc is currently offline  glwgmc   United States
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Registered: June 2004
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Senior Member
We are nearing the 8000 mile point on the SandJ engine in the Royale and the 1500 mile mark on the one in the Clasco. So far I am most impressed with both of them. They are very strong with high and steady oil pressure (50 to 60 hot cruise and 30 to 40 hot idle). The one in the Royale has now fully loosened up and is fully broken in so it is quite a bit more powerful than the not yet broken in engine in the Clasco. We are on our way north on the I5 going over the five passes for Sharon to have some upper and lower eye lid surgery on Thursday and are in the Royale so she will have the large king sized plus bed for her recovery.

It is so relaxing to climb mountain passes so easily with no down shifting required and no need to keep your eyes on the gauges. Both coaches are geared the same, both have an aluminum radiator, both are set with cam timing four degrees advanced, both have the same tires, both have new carb and distributor, so are easy to directly compare. The only difference is the Royale is a bit heavier, has more sound deadening, has a Patterson carb and distributor, and has headers while the Clasco has stock exhaust manifolds and a JimB carb and distributor.

So far, the as yet broken in SandJ engine in the Clasco does not seem as strong as the one in the Royale. And, I still have not yet sorted out why the Clasco runs too cool while the Royale laughs at hills and stays right around the 195 thermostat temp. I have a 180 in the Clasco and it runs well below that.

Based on my very positive experience with both SandJ engines I would not hesitate to recommend them to any of you in need of a new engine. I also would not hesitate to recommend JimH to do the RandR.

Jerry

Jerry Work
The Dovetail Joint
Fine furniture designed & hand crafted
in the 1907 former Masonic Temple building
in historic Kerby, OR
http://jerrywork.com

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Jerry & Sharon Work
78 Royale
Kerby, OR
Re: [GMCnet] Two SandJ engine report [message #272589 is a reply to message #272586] Tue, 24 February 2015 22:49 Go to previous messageGo to next message
zhagrieb is currently offline  zhagrieb   United States
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Location: Portland Oregon
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Best of luck to Sharon.

Glenn


Glenn Giere, Portland OR, K7GAG '73 "Moby the Motorhome" 26'
Re: [GMCnet] Two SandJ engine report [message #272591 is a reply to message #272586] Tue, 24 February 2015 23:18 Go to previous messageGo to next message
cbryan   United States
Messages: 451
Registered: May 2012
Location: Ennis, Texas
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Senior Member
Jerry,

Sounds much like that headers might help. Now, if you could trade the manifold with the header between the Royale and the Clasco and retest, we could get an idea about the value of the headers. Rob Mueller cites a 17 hp increase for headers. Sounds about right to explain the difference. I think that a change of thermostat in the Clasco would be helpful. Sometimes I have experienced that old coolant gets acidic and damages thermostats, or so I was told by a friend in the repair business.

I sure don't expect you to switch those exhaust appliances. But, it would be interesting. You note that the quieter is the Royale with headers. I read that headers, even while muffled well were noisier. Another myth busted. It is also true that changing exhaust systems might involve rejetting the carbs, as well. Or, just to keep busy, change the carbs as well, after seeing if the power followed the headers.

Best,

Carey


Carey from Ennis, Texas 78 Royale, 500 Cadillac, Rance Baxter EFI.
Re: [GMCnet] Two SandJ engine report [message #272615 is a reply to message #272591] Wed, 25 February 2015 10:29 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Location: Sydney, Australia
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G'day,

It was 17 ft lb torque and 10 horsepower at 3200 rpm, which is way above the "normal" operating RPM range of our engines. If you
look at the data down where we run you'll see it is much less.

http://www.gmcmhphotos.com/photos/aa-miscellaneous-photos/p40002-manifolds-vs-headers-455-olds.html

This data is from the same engine a couple of days apart and AFAIC clearly demonstrates the value of headers when it comes to
performance.

Here's the source of the data: http://www.gmccoop.com/koba_built_motors.htm

Regards,
Rob M.
The Pedantic Mechanic
USAussie - Downunder
USA '75 Avion - Double Trouble TZE365V100426
AUS '75 Avion - The Blue Streak TZE365V100428


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Carey Bryan
Sent: Tuesday, February 24, 2015 11:19 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Two SandJ engine report

Jerry,

Sounds much like that headers might help. Now, if you could trade the manifold with the header between the Royale and the Clasco
and retest, we could get an idea about the value of the headers. Rob Mueller cites a 17 hp increase for headers. Sounds about
right to explain the difference. I think that a change of thermostat in the Clasco would be helpful. Sometimes I have experienced
that old coolant gets acidic and damages thermostats, or so I was told by a friend in the repair business.

I sure don't expect you to switch those exhaust appliances. But, it would be interesting. You note that the quieter is the Royale
with headers. I read that headers, even while muffled well were noisier. Another myth busted. It is also true that changing
exhaust systems might involve rejetting the carbs, as well. Or, just to keep busy, change the carbs as well, after seeing if the
power followed the headers.

Best,

Carey


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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Two SandJ engine report [message #272619 is a reply to message #272586] Wed, 25 February 2015 11:09 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Location: S. Ontario, Canada
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Jerry,
The thermostat sets the minimum engine operating temperature once the engine has warmed up. If your engine has a 180 thermostat but as you say, runs much cooler than that,
then:
-the thermostat is defective in that it is opening too soon, or maybe stuck open
-your engine temperature sender is faulty
-your engine temperature gauge is not reading correctly

Just my farmboy mechanic troubleshooting thoughts.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: [GMCnet] Two SandJ engine report [message #272623 is a reply to message #272586] Wed, 25 February 2015 13:14 Go to previous messageGo to next message
Darryl is currently offline  Darryl   United States
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Location: Northern California
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Jerry

I've got about 7,000 miles on my S&J 403 installed about a year ago. It's running strong. I'm very pleased.

Darryl


Darryl Meyers 1978 Eleganza II El Dorado Hills, CA
Re: [GMCnet] Two SandJ engine report [message #272625 is a reply to message #272586] Wed, 25 February 2015 13:27 Go to previous messageGo to next message
RandyM is currently offline  RandyM   United States
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Registered: December 2013
Location: San Antonio, TX
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Member
Are your engines 403s or 455s?

Besides your carb, distributor and exhaust, is there any internal changes to the stock set-up?

Randy
Re: [GMCnet] Two SandJ engine report [message #272632 is a reply to message #272615] Wed, 25 February 2015 14:03 Go to previous messageGo to next message
cbryan   United States
Messages: 451
Registered: May 2012
Location: Ennis, Texas
Karma: 3
Senior Member
[quote title=USAussie wrote on Wed, 25 February 2015 10:29]G'day,

It was 17 ft lb torque and 10 horsepower at 3200 rpm, which is way above the "normal" operating RPM range of our engines. If you
look at the data down where we run you'll see it is much less.

http://www.gmcmhphotos.com/photos/aa-miscellaneous-photos/p40002-manifolds-vs-headers-455-olds.html

This data is from the same engine a couple of days apart and AFAIC clearly demonstrates the value of headers when it comes to
performance.

Here's the source of the data: http://www.gmccoop.com/koba_built_motors.htm

Regards,
Rob M.
The Pedantic Mechanic

Rob,

I appreciate this correction. It's interesting to see those dyno differences, close to apples and apples. It's 17 lb/ft, and 10 HP.
Thanks, I thought I couldn't take your name in vain without your noticing!

Carey


Carey from Ennis, Texas 78 Royale, 500 Cadillac, Rance Baxter EFI.
Re: [GMCnet] Two SandJ engine report [message #272638 is a reply to message #272625] Wed, 25 February 2015 14:50 Go to previous message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
Karma: -62
Senior Member
There is not much difference. They are both .030" Over born 455. Both have
the same camshaft, and are both advanced 4 degrees from straight up. Both
have "J" heads. Both have the same cast iron exhaust manifolds. Both have
the same exhaust systems. Both have exhaust cross overs blocked. Both have
HEI ignitions, and quadrajet carbs. Both engines crank the same compression
pressure. Pea's in a pod? Maybe not, but close. As Jerry said, one is well
broken in, one is new and tight. When the clasco loosens up fully, we will
optimize tune up specs.
Jim Hupy
Salem, Or
78 GMC ROYALE 403
On Feb 25, 2015 12:21 PM, "Randy Meek" wrote:

> Are your engines 403s or 455s?
>
> Besides your carb, distributor and exhaust, is there any internal changes
> to the stock set-up?
>
> Randy
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