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428 thermostat

Started by 2112, March 18, 2018, 02:31:20 AM

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shelbydoug

#15
Quote from: zray on March 21, 2018, 10:21:55 AM
Quote from: 427heaven on March 21, 2018, 09:30:04 AM
I think we understand the law of averages that the auto manufacturers needed an AVERAGE temp T stat for cars shipped all over the world. 180 seemed to be the number-......."

Well, 180 was NOT the number that the Ford engineers were thinking of in 1966 across the entire V-8 range of engines, small blocks, and the  big blocks that were going into the full size Fords too.  They wanted the operating temperature  to be 190 minimum, and 200 - 212 was optimum.

Am still looking for my '67/'68 shop manual, so can't say for sure, . But I do know for certain that  '65/'66/'67 HiPo and the  & C code 289's, as well as the big block engines going in the full size cars in 1966, did not come from the factory with a 180 degree thermostat. They  came with 190 / 192  thermostats. Those don't even fully oven until the engine is 210 - 212 degrees F.

I'm always amazed at the number of people who think 210 - 212 degrees is overheating.....

Z

You are absolutely correct. These are 12 psi systems which means overheating with 50/50 is around 240.

I know that the issue with the thermostats is really that particularly with the big blocks, they can be very difficult to restart when hot, so people tend to want to over cool them.

I also see this even with racers that want to cool the oil down to around 180 degrees and take steps to do that.

Somewhere over 212F is where you want the oil temps to be. Probably a minimum of 220 is about right.



The discussion of -0100 with the oil cooler is a good example. The documentation showing that oil temp over 230 needed to have cooling considerations. TO ME clearly the number that Engineering was aiming at was 230.

The higher the compression ratios on these engines, even the 289's, the more difficult it is to even turn them over hot.

I truly believe that is where all this issue stems from.


I have seen my starter wire SMOKING from trying to restart a hot engine. Mr.Gaines is going to be very upset when he reads this BECAUSE I MELTED an original "production" starter solenoid.  Melted to the point that it could be in a Salvatore Dalli abstract painting. His painting is valuable. My solinoid isn't since it's now garbage?



One VERY critical factor I have found is that virtually no one checks the sealing ability of the radiator caps.

I bought a Stant cooling system tester kit and have found it to be invaluable. You pressurize the complete system with it to make sure it holds pressure AND you pressure test the caps with it.

It was a hundred bucks and worth it's weight in gold!



I'm embarrassed to admit that I had several caps that wouldn't hold the pressure.

The "Mustangs" need to hold 12 psi and the Pantera 15. If they don't, you get these phantom over heating issues.



I get the part that people are stubborn and don't want to listen. It took me thirty years to get on board with this and see the light. You could use me as the poster boy for that?  ;)

The first thing I do with a new radiator cap is test it for pressure holding ability. I would say that one out of three or one out of four NEW caps leak from my testing.

That right there is a problem if you can't test them yourself? ;D


The other place to look is the neck of the radiator itself. If it isn't perfectly flat, it won't permit the cap to seal entirely.


I have seen 289's with pop-up pistons (a c/r of around 11.8:1) not able to turn over hot with the stock equipment starter. MANY GT500 owners have gone to aftermarket starters for the cranking ability. Stock even 10:1 is marginal for the starter. Cold ok, but hot, probably not until the thing cools off in a hour or so?

68 GT350 Lives Matter!

shelbydoug

Quote from: 6s1802 on March 21, 2018, 11:00:49 AM
I overheat at 210

That is NOT POSSIBLE IF your system is holding pressure. That simply means YOUR system is open to atmospheric pressure.
68 GT350 Lives Matter!

zray

Quote from: shelbydoug on March 21, 2018, 11:12:04 AM
Quote from: 6s1802 on March 21, 2018, 11:00:49 AM
I overheat at 210

That is NOT POSSIBLE IF your system is holding pressure. That simply means YOUR system is open to atmospheric pressure.

+1000

I would ask 6s1802 what is your definition of overheating, what are the symptoms ?  As ShelbyDoug says, if your system is holding 12 - 13 lbs. pressure, the coolant cannot boil at 210 or even 220.



Z



shelbydoug

I think one of us should post the anti-freeze chart here that shows boiling temps with 50/50 at various temps?

I don't have the time at the moment. Maybe later? Anyone want to do it? I think it is on the Prestone web page?
68 GT350 Lives Matter!

csheff

Is it still good to drill a small hole top side of thermostat as suggested in original posting on old site?

Bob Gaines

Quote from: csheff on March 21, 2018, 11:39:56 AM
Is it still good to drill a small hole top side of thermostat as suggested in original posting on old site?
Yes
Bob Gaines,Shelby Enthusiast, Shelby Collector , Shelby Concours judge SAAC,MCA,Mid America Shelby

KR Convertible

Quote from: csheff on March 21, 2018, 11:39:56 AM
Is it still good to drill a small hole top side of thermostat as suggested in original posting on old site?

It is beneficial on the original style to allow air pockets to bleed out.  I doubt you would need it on the high flow design, if there's even room to drill the flange.

zray

#22
Quote from: shelbydoug on March 21, 2018, 11:32:22 AM
I think one of us should post the anti-freeze chart here that shows boiling temps with 50/50 at various temps?

I don't have the time at the moment. Maybe later? Anyone want to do it? I think it is on the Prestone web page?

couldn't navigate the Prestone site to find the chart, but there's this:

https://durathermfluids.com/pdf/techpapers/pressure-boiling-point.pdf

note,  found a lot of misleading info on the Evans waterless coolant website:

https://www.evanscoolant.com/how-it-works/benefits/no-overheating/


".....Water turns into steam at 212°F. Mixing traditional ethylene glycol antifreeze with water in a 50-50 ratio increases the boiling point to 223°F, which is close to the operating temperature of an engine. Evans waterless coolants have a boiling point of over 375°F, far above the operating temperature of the engine....."

They conveniently leave out the fact that when the system is pressurized, the boiling point of 50/50 antifreeze is much much higher.


Z

NOTE:  at the bottom of the page Evan's does mention that pressurized systems have a higher boiling point, only the poo-poo the effectiveness of  the pressure on actual boiling point. not impressed .

shelbydoug

#23
That's the chart. Thanks.


It clearly shows that in order to boil over at 212 it would need to have no anti-freeze and completely open to the atmosphere.

The Pantera people constantly go through this "I'm overheating" thing.

They see a water temp of around 240 on a gauge that only goes up to 230, in a 15psi system that is good for 259.


With the Shelby's it's mostly the big block SEEMS to run hotter? It DOESN'T.  It just takes up more room in the engine compartment, so it's tighter quarters. The flow through the radiator dumps into the engine compartment with less room to dissipate into.

Plus you have a temp gauge that doesn't show you actual numbers. Just high/low.

"Just adds to the paranoia. Like a Police car behind you".  8)



It is undeniable though that it can be a challenge to restart a hot 427 or 428. No question. I've even heard this from the 427 Cobra owners back in the day.

The 427 s/c had two batteries behind the passenger seat for access but you don't need two batteries for access, just to restart a hot engine.

A Tilton starter fixes a lot of that issue though AND you need to keep the battery as fully charged as you can. That means you need to run the engine for about 20 minutes EVERY DAY with an original type battery. Plus the original battery is debatably, as batteries go, on the attractive side but those things would turn into a corpse the first winter it went through.
68 GT350 Lives Matter!

2112

Doug, I wanted to thank you for breaking your long posts up into paragraphs. Even if they are short ones.

Those long run-on single paragraph posts, with zero breaks, are murder to read thru on a screen.

shelbydoug

#25
Quote from: 2112 on March 21, 2018, 12:47:03 PM
Doug, I wanted to thank you for breaking your long posts up into paragraphs. Even if they are short ones.

Those long run-on single paragraph posts, with zero breaks, are murder to read thru on a screen.

Even harder to write. Sorry. One thought brings up another and if two people tell two people...etc

They actually are multiple thoughts and need to be punctuated as such or better.  I just don't think some answers are necessarily simple ones, just presented better by me. Me bad.
68 GT350 Lives Matter!

pbf777

#26
160 is too low for optimum power and minimum wear.Z [/quote]

     O.K.. Allow me to jump in here and stir the pot some. 

     This simple, strait-to-the-point statement is not necessarily incorrect, but also not necessarily accurate, depending on the many variables at hand. i.e. "IT DEPENDS"    ;)

     There are some ultimate requirements and limitations associated with nominal engine temperature as perceived (note that the gauge value does not necessarily indicate the actual sum at critical points), but, this required value as delivered by the thermostat may vary. And, this could definitely turn into a book, lets just list a few simplistic observations.
     The oil needs to be of a temperature which promotes good flow; adequate heat to add vaporization of fuel particularly within the induction tract, but not to ignore said value within the combustion area also; and evaporation of water condensation within the crankcase; but, not excessive temperature values which may exceed these requirements, and may offer negative effects including, but not limited to, initiating a detonation scenario upon the combustion process.
     If I were to identify a minimum & maximum temperature sum of the typical American V8 engines' oil and water, ideally before one entertained placing this engine under any significant some of duress: 140° - 220°, give or take? A few considerations for the cooler or warmer operating temperature might be:
     COOLER = horsepower potential due in part to cooler & denser inlet charge, reduction of detonation & pre-ignition events, improved lubrication & cooling values of the oil providing reduced wear on load-bearing surfaces, etc.; perhaps indicating that for higher R.P.M.s, loads and durations, one may chose to utilize a cooler thermostat value. Also, in the warmer environments, unfortunately the cooler radiator is less efficient as increasing the temperature differential between it and the ambient temperature increases its' effectiveness.
     WARMER = improved "efficiency" with improved air/fuel mixing and combustion (particularly at low engine speeds), improved emissions acceptance, also a reduction in wear from "fuel-washing" and pollution of the crankcase, and with the reduction of viscosity of oil (due to heat) a reduction in pumping losses, older engines with excessive clearances might even "seal-up" better with heat and reap an improvement in operation, etc. Oh, and for the folks in the northern territories, the heater works better! Therefor, if one "short-hops", and or "puts-about", I would definitely install a warmer thermostat value.
     One of the real concerns, often overlooked, within the subject of engine temperature is not so much whether it's 20° more or less, but rather if it can be maintained at a constant sum. As the castings do not really care what temperature they are in operation (within reason), but do change dimensionally, and therefor loading and surface wear characteristics of so-called "familiarized wear surfaces" fluctuate imparting increased wear rates.
     Just a few thoughts, left out a lot, but this could consume one in study.    ;)

     Scott.


     
     
     

     

2112

Instead of exactly when a thermostat starts to open, maybe a good question to ask would be do all thermostats flow equally once they are fully open, at say 200°?

shelbydoug

Poor flow would be indicated by a steady rising operating temperature. Hot spots inside of the engine are more important.
68 GT350 Lives Matter!

427heaven

Well we could go on forever with this, but what about pinging when you are just toodling around the neighborhood at 200 degrees temp say cruising the LV strip at 110 degrees outside. All things equal quality, of fuel,timing,carbs etc. In many of my cars I don't even run a T stat I just change the hole size in a water flow restricter. your not trying to open up anything your just trying to regulate your coolant flow capabilities. With this you can find the sweet spot in any car. Not rocket science,just a little trial and error.