Author Topic: Will my GT500 overheat when I get done building it?  (Read 5074 times)

67 GT350

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Re: Will my GT500 overheat when I get done building it?
« Reply #15 on: March 25, 2019, 08:03:31 PM »
Off topic, but what about small block, what should they run at and what thermostat should be used? I was always under the old school thought that you want your motor running the coolest? Guess I am wrong?
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acman63

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Re: Will my GT500 overheat when I get done building it?
« Reply #16 on: March 25, 2019, 08:55:45 PM »
nobody has mentioned the engine build.

did you take the block and heads  to a rust stripper to make sure all the insides are stripped of rust?
did you have the block baked out to clean all the passages after stripping?
what is the overbore more than 30
did you use torque plates to machine the bores - they simulate a head being installed,  we measured a block in 3 places  prior to installing the torque plate and it was .004  difference after sitting overnight -  rings have to move that far each time up an down
did you machine the block at operating temp - real high end shops can do this
did you have the block blueprinted?  square the decks

Ive found that if you do these the engine runs very smooth and cooler  -  its not something the normal engine builder does

I hadn't heard of machining the block at operating temperature before. I like it, but guess it would be hard to find a shop to do it.

Are you  saying up to .030" should be ok for the bore increase?

I think they started doing that with Nascar engines  which makes sense to machine block at the temp its going to be, just like it makes sense to machine a block with the torque plate installed

30 0ver FE  should be OK with a proper build

BarryR  has a great reputation with FEs
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shelbydoug

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Re: Will my GT500 overheat when I get done building it?
« Reply #17 on: March 26, 2019, 07:32:03 AM »
Off topic, but what about small block, what should they run at and what thermostat should be used? I was always under the old school thought that you want your motor running the coolest? Guess I am wrong?

An engine is an engine. The same criteria applies to all.

One thing that I noticed on rebuilds is that the solvent used to "boil out" blocks, heads and other components has changed. Ten years ago when I got my stuff back out of the "tank", they looked like new castings with no remnants of anything. Now it doesn't even take all of the paint off?
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Re: Will my GT500 overheat when I get done building it?
« Reply #18 on: March 29, 2019, 09:24:07 PM »
I have a '67 GT 500 with a healthy build. I am running distilled water and a wetting agent. It doesn't even run anywhere near mid-gauge. I would not run a 160 Thermostat. Run the 180 FlowKooler high flow.  This is the one I am running.  -Keith

https://www.summitracing.com/search/model/fe?keyword=robert%20shaw%20thermostat&ar=1&kr=robert%20shaw%20fe%20thermostat
« Last Edit: March 31, 2019, 12:43:58 AM by 1967 eight barrel »

tonys_shelby

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Re: Will my GT500 overheat when I get done building it?
« Reply #19 on: March 30, 2019, 11:12:57 AM »
Keith are you running all rest of the stock equipment, water pump, raid, etc?

1967 eight barrel

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Re: Will my GT500 overheat when I get done building it?
« Reply #20 on: March 30, 2019, 10:28:39 PM »
My only change to the cooling system is the Edelbrock water pump. The radiator and everything else is OE Ford. Make sure your fan clutch is in good working order too.

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« Last Edit: March 31, 2019, 12:34:54 AM by 1967 eight barrel »

Mike James

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Re: Will my GT500 overheat when I get done building it?
« Reply #21 on: March 31, 2019, 10:14:10 PM »
I was having overheating issues during break-in.  Bob Gaines recommended a 160 high flow thermostat and I advanced the timing by ear, instead of with the light.  I probable tinkered with the timing for a day until it started just right, accelerated hard, and didnít ping.  Also make sure to check your jetting and have jets close to 67 (adjust from here based on elevation above sea level).

My car doesnít even come close to overheating in 115 degree days in Arizona now.

shelbydoug

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Re: Will my GT500 overheat when I get done building it?
« Reply #22 on: April 01, 2019, 06:49:46 AM »
That's as it should be. The weakest link, even on a properly running FE is a hot restart. Often the starter wants to run away and hide.

Actually that is a little unfair because even a high compression small block will have the same problem.

The "issue", if you want to call it that, is accentuated by a car with A/C and automatic transmission.

Brand new Ford starters will normally handle it adequately but they tend to loose torque as the armature outside diameter wears down. Even a rebuild won't hope that. In fact it will often make it worse since a good rebuild will put that in a lathe to be recut.

Personally I long ago went to the little Toyota sourced aftermarket high torque/race starters. So far I haven't had one of those starter fail.
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pbf777

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Re: Will my GT500 overheat when I get done building it?
« Reply #23 on: April 01, 2019, 08:37:23 PM »
It is a 100% No expense spared rebuild .030 bore by Barry Rabotnick of Survival  in MI

     If so, then what was the resultant cylinder wall thickness, as indicated by a sonic test procedure, post finish bore preparation; as this may be a indicator of issues of any excessive core-shift within the block casting, and its' resultant cooling difficulties in operation later.     ???

     Remember, the FE block has been described as being of "Thin-Wall" casting technique, and many would be amazed at how thin these castings are in places sometimes, and this can lead to insurmountable heat invasion into the cooling system.    :o

     Scott.



1967 eight barrel

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Re: Will my GT500 overheat when I get done building it?
« Reply #24 on: April 03, 2019, 12:51:12 AM »
You can be rest assured that all is well if Barry Robotnic did the rebuild. He would have never built the engine without a sonic check with adequate thickness. I wouldn't worry about anything except being sure your cooling system is up to par. 160 is too cool. Don't run under 180. It causes excessive wear. Keep in mind that too cool will wear an engine out. A radiator core in proper repair, fan clutch, quality water pump impeller and fan shroud helps tremedously. If you're not planning on certain judged classes I would go with an edelbrock water pump.  I would run distilled water and water wetter, not coolant as well. If you're in a climate that freezes,you have little choice but to use antifreeze.

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Bob Gaines

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Re: Will my GT500 overheat when I get done building it?
« Reply #25 on: April 03, 2019, 01:47:20 AM »
Not related to cooling but something that is overlooked after you get done rebuilding your engine is the heater core. They have a bad habit of blowing out after fresh rebuilds . I would change it or have it pressure checked while the engine is out . Nothing messier then having one blow out during a test drive and you get on it to test the new engines performance. That extra pressure can burst a weak heater core.  Suddenly your interior fills up with possibly gallons (depending on how bad the core ruptures) hot water, steam and ether mixed with water wetter or antifreeze. Both can be a sticky mess on the carpet . Just a reminder.
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tonys_shelby

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Re: Will my GT500 overheat when I get done building it?
« Reply #26 on: April 03, 2019, 06:30:40 AM »
All good stuff,  everything is new or rebuilt including heater core.  I did rebuild the water pump I would like to keep the original one. Rebuilt with the correct Heavy Duty size impeller/ shaft bearing etc from Dead Nuts On so I'm hoping that will be good. It does sound like that is the " weak link" and we will see if I need to change it I guess but I will try and see. Now I will need to find a place to take the radiator to and have it gone through, cleaned out pressure tested etc.

shelbydoug

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Re: Will my GT500 overheat when I get done building it?
« Reply #27 on: April 03, 2019, 07:20:54 AM »
All good stuff,  everything is new or rebuilt including heater core.  I did rebuild the water pump I would like to keep the original one. Rebuilt with the correct Heavy Duty size impeller/ shaft bearing etc from Dead Nuts On so I'm hoping that will be good. It does sound like that is the " weak link" and we will see if I need to change it I guess but I will try and see. Now I will need to find a place to take the radiator to and have it gone through, cleaned out pressure tested etc.

Pressure test the entire system once assemmbled and the cap separately. The system needs to hold 12 psi WITHOUT leaking down. 15 wouldn't be a bad idea. TEST THE CAP.
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Re: Will my GT500 overheat when I get done building it?
« Reply #28 on: April 03, 2019, 12:07:57 PM »
The caps are #13. The system will bleed down after a bit, but 15LBS is a good idea. A lot of the heater cores are aluminum now as well. I'd stay away from the cheap ones. New motors are tight and tend to run a bit warmer than those that have been run in.
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