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Cooling System Woes.....What am I doing wrong?

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Fabman

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Oil cooler is hanging from the front crash bar, maybe 3ish inches fore of the AC condenser.

Good point on the tstat. Stuck partially closed you're thinking?
Hanging the oil cooler like that is sub optimal. Should be up against the radiator with its own little shroud so air HAS to go through the cooler AND the radiator. Right now your basically blocking the radiator with it and neither one is particularly efficient.
 
Hanging the oil cooler like that is sub optimal. Should be up against the radiator with its own little shroud so air HAS to go through the cooler AND the radiator. Right now your basically blocking the radiator with it and neither one is particularly efficient.
Earlier in this thread you mentioned updating the early 3v cars to the later water flow paths of the 08 09 cars. Do you have any additional information about that? Looks like @Boone has some info, I’ll be searching but would love some assistance.
 
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Again, get rid of the under drive pulleys. This isn’t a drag car so stop under driving the water pump. The under driven water pump will cause your engine to run hotter. Get rid of the “coolant” and run straight distilled water with two bottles of water weter. Check the thermostat. After that, you need to consider a larger capacity radiator.
 
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Fabman

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Again, get rid of the under drive pulleys. This isn’t a drag car so stop under driving the water pump. The under driven water pump will cause your engine to run hotter. Get rid of the “coolant” and run straight distilled water with two bottles of water weter. Check the thermostat. After that, you need to consider a larger capacity radiator.
Correct.
 

Fabman

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Earlier in this thread you mentioned updating the early 3v cars to the later water flow paths of the 08 09 cars. Do you have any additional information about that? Looks like @Boone has some info, I’ll be searching but would love some assistance.
The early 3 valves have a goofy set up with a remote thermostat and 2 upper radiator hoses one coming from the head and one going to the thermostat. Hard to explain but it sucks. Remove the thermostat housing and use one radiator hose and plug the other. I think we used the 2008 lower hose as well. Boone has my old set up so he knows what I’m talking about.
 
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I just ordered an OEM water pump pulley and will compare the size to the steeda one that's on the car. I wasn't able to find the dimensions online. I'm hoping the OEM pulley is smaller and will turn the pump faster.

At this point I'm too lazy and not enough convinced it'll help to go about changing the crank pulley. Will report my findings.

Car already has a bigger radiator and distilled water+water wetter BTW.

Multiple people have claimed UDP's are a good thing for a road race car. But, every water pump is different so. Can't really use that as gospel.

It's a real bummer it's not possible to get pump curves for the OEM pump. That's all we need to know to solve this issue. If pump flow is linearly increasing GPM at OEM accessory speeds from 4k-7k RPM, then the issue is solved. But if the pump curve tapers off in the 4k-7k RPM range, then the answer is not so simple as pump is being under driven.
 

Fabman

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Fabman

Dances with Racecars
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Exp. Type
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Pleasanton: 1/2 way between Sonoma and Laguna Seca
Here it is....

stock vs SVT.PNG

Notice the fan is also a bigger diameter.
 
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Yes, besides the flaps there is one more blade in the fan and they are thinner so free air can pass through them easier. The stock GT fan has thicker blades and pretty much blocks the free air.

Here it is....

View attachment 68283

Notice the fan is also a bigger diameter.
Amazing, thank you!!

I never realized how much bigger the blades were on the OEM fan....

Fabman, did you do any testing with having the fan motor on/vs off while on track?
 
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Obvious question but the vanes on your AC condenser are all straight and clear, correct? At least on my '11 the condenser sits totally unprotected out front and over the years road junk totally collapsed and blocked a large portion of the condenser and the radiator behind it. If the condenser currently is sitting between your oil cooler and radiator, you might not notice prior damage?
 

Fabman

Dances with Racecars
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Pleasanton: 1/2 way between Sonoma and Laguna Seca
Amazing, thank you!!

I never realized how much bigger the blades were on the OEM fan....

Fabman, did you do any testing with having the fan motor on/vs off while on track?
I've been running electric fans on race cars since 70's. Initially I did a LOT of testing and free air always out flowed fan driven air by a LOT. This included both engine driven and electric fans, both shrouded and un shrouded.
On my stock car if I forgot to turn the fans off before the green flag the temp would climb fast, soon as I turned them off it would cool right down.
I haven't tried this with the Mustang because in my mind I've already answered that question.
 

Fabman

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Well, again, even though the OP doesn’t want to hear it, none of the factory built or third party built race cars ran under drive pulleys and the all had factory water pumps.
 
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Wanted to update the group here:

Sadly I don't have very good data other than the fact that I can still get the car to overheat (230+F).

I installed the SVT GT500 fan shroud, and an OEM water pump pulley (by my calculations, water pump is spinning 30% faster than it previously was, but still 30% slower than OEM speed. So to clarify, I previously had the water pump spinning 60% slower compared to OEM).

In morning sessions (55-70f ambient) the coolant temperature never went above 225 degrees which was GREAT. But in the afternoon sessions, ambient temperature were in the 75-85 range and I could get the car to hit 230 degree coolant temp, car would pull timing, etc after 1-2 hot laps.

The rate at which the coolant temps climbed seemed to be less than what was experienced previously. I think the cooling system capacity is definitely improved but it isn't as good as it needs to be.

Will look into a different radiator and putting stock crank pulley back on next.

Thank you all for the help, let me know if you have any other ideas.
 
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A noobie question for the group:

1642542365153.png
Can I remove the thermostat without draining the coolant (just want to test to see if the tstat is the culprit here)?

I'm 800 miles away from my car at the moment but if I remember correctly, the outlet of part#8592 is the top hose (hot side) of the radiator. So in theory could I unscrew part# 8592, remove part#8575 and then replace part#8592 without draining the coolant? I would burp the system but I don't want to deal with jacking the car up, draining the coolant, etc. just to do a little t-stat test.

Thanks everyone.
 
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A noobie question for the group:

View attachment 71919
Can I remove the thermostat without draining the coolant (just want to test to see if the tstat is the culprit here)?

I'm 800 miles away from my car at the moment but if I remember correctly, the outlet of part#8592 is the top hose (hot side) of the radiator. So in theory could I unscrew part# 8592, remove part#8575 and then replace part#8592 without draining the coolant? I would burp the system but I don't want to deal with jacking the car up, draining the coolant, etc. just to do a little t-stat test.

Thanks everyone.

Get ready to catch some water, but it's not a deal breaker, I'm going to say a little over a quart.
 

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