I hear a lot of talk about how the GT500's especially with inboards can overheat. Is this a real problem and is there something I should do to head this off? Not use stock radiator, fan etc? Will have everything newly rebuilt, engine, water pump, clutch fan on and on. Or will this really not be a problem?
Use a 180 or 190 deg thermostat as it keeps the coolant in the radiator longer where it is cooled, then circulated. Your water pump should be for a big block. Some people put the wrong impeller in when it is rebuilt as they don't think it matters.... it does. As long as your block and radiator are clean there should not be an issue.
A 180 or 190? What about a 160?
Use at least a 180, for sure. In my GT 500, with a 600 hp 427 with 12.5 compression, I ran mostly distilled water, with two small bottles of water wetter, and a little coolant. Never overheated in Texas summer with stock radiator and 180 thermo.
It all depends on what you consider over heating?
Do you mean "boil over point"?
The GT500 has a 12 psi pressure cap and system. With a 50/50 mixture of anti-freeze, it won't boil over until around 240F. Anything under that is not over heating if you are talking about boilover.
Do BB Mustangs run hot? You bet ya'! Try one with an automatic transmission with A/C in Phoenix? ;)
Probably the biggest problem is going to be a restart when the engine is at "full operating temps".
Secondarily, with a '67 GT500 in particular, the carbs will boil over immediately after shut down as built and delivered new.
The best solutions to that is to isolate the carbs and to put in a high torque starter. Personally I wouldn't run anything but a 160 thermostat and a full three core radiator.
I absolutely plan on isolating the carbs and fuel logs and gear reduction starter. Don't want it running at 210+ at a stop sign hurting anything puking out water.
Quote from: Frankie on March 25, 2019, 08:46:19 AM
A 180 or 190? What about a 160?
Not a good idea. Lot of opinions about why not. The engines have to reach the designed-to-operate temperature and 160 doesn't allow that to happen. On a big block, get the distributor set up correctly then time the engine correctly. A timing issue is sometimes seen in running hot/boil over.
Fellas. You are both missing the point. The normal operating temperature of this engine is in the 220 range. That is NORMAL. It's not overheating there.
It's actually good to at least 230-235.
Look at the 50/50 anti-freeze chart at 12 psi. That will show you what is normal.
There is no place that you are going to get a 428 to run at 212 or over unless you are talking Antartica.
This is the same issue people have with Panteras. As soon as they see 230 on the gauge they become "Chicken Little" and right away, "the sky is falling".
The pressurized system is used for a reason. If you are boiling over at 212F then you radiator cap isn't permitting the system to properly pressurize.
Are you saying that from the factory the temp gauge would be reading dead center of "normal" and the engine temp would be at 230? I don't know big blocks much witch is why I ask these questions but it seems like when you parked it you would be walking out to a puddle of antifreeze when you came back to the car? That's my goal drive it around and not freak that the temp gauge is climbing and leaving a streak of water/antifreeze. Can I do that with stock components?
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
It is a 100% No expense spared rebuild .030 bore by Barry Rabotnick of Survival in MI
Quote from: acman63 on March 25, 2019, 10:40:10 AM
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?
Quote from: tonys_shelby on March 25, 2019, 09:26:07 AM
I absolutely plan on isolating the carbs and fuel logs and gear reduction starter. Don't want it running at 210+ at a stop sign hurting anything puking out water.
230 would be considered normal. 220 would be better. 210 isn't hot enough. As discussed all clearances spec'd by manufacturers are stated for "normal operating temps". The temperature is part of the clearances specified.
All engines NEED to operate above the boiling point of water (212F) in order to boil out the moisture in the engine oil. Otherwise all you are doing is creating oil sludge which WILL create excessive engine wear and accelerate it.
You need to be careful with this also with oil coolers. They really should be run with an oil thermostat that doesn't open until it's over 212. Otherwise you are actually over cooled.
Engineering wise, this was all taken care of with a 12 psi cooling system. It raises the boiling point of the coolant to about 242 F. That's the boil over point.
What exactly the silly stock temperature gauge indicates is almost irrelevant to this discussion. It has no temperature markings. You need an accurate way to measure the temperature and give you an accurate reading.
That all makes perfect sense!
I have found that it is beneficial to add a GANO or TEFBA filter into the upper hose
to catch rust particles and debris left over from the rebuild process. This saves
the radiator. We have caught debris in all the engines that have been rebuilt.
Sue
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?
Quote from: 2112 on March 25, 2019, 11:10:07 AM
Quote from: acman63 on March 25, 2019, 10:40:10 AM
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
Quote from: Frankie 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?
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?
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
Keith are you running all rest of the stock equipment, water pump, raid, etc?
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.
-Keith
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 didn't 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 doesn't even come close to overheating in 115 degree days in Arizona now.
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.
Quote from: tonys_shelby on March 25, 2019, 10:54:39 AM
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.
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.
-Keith
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.
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.
Quote from: tonys_shelby 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.
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.
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.
-Keith