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

23
11
CA
Hello everyone,

I am at a loss.

S197 mustang with a lowly 3v 4.6 making 315whp.

  • Fluidyne Radiator
  • Edelbrock HV water Pump
  • UDP's
  • Massive hood louvers
  • Ducted in radiator
  • Oil cooler
  • Fresh coolant w/Redline water wetter+distilled water

Yet, somehow, I can get the ECT's so hot in weather that is over 75°F, that the car will cut power (pull timing) on me. I have an autometer gauge that's taking coolant temperature in the engine block. Cruising, sits at 190°F. 7/10ths pace on track, reads around 220°F. A lap at Race pace, the gauge will hit 230°F, car will cut power. If I continue to stay in it, the car will get up to 240°F. I've never pushed it beyond that for obvious reasons.

Why is it that nobody else has this problem?

Keep in mind, my stock coolant gauge shows no difference between 190°F cruising and 240°F overheating. So before you answer, please read this Disclaimer, because it happens every time I ask this question:

Before you reply saying you can run your car 10/10ths in 100°F ambient heat without issue, please consider that you are either not driving as hard as me, you aren't able to feel the car cut power, or you don't have the level of information that I have in regards to temperatures because you are relying on the stock gauge.

So to summarize I'm looking for good data from people who genuinely have a car that they can beat on lap after lap in hot ambient temps. Maybe this is a totally unrealistic expectation? But I'd like to think it isn't considering the FR500S program, spec iron cars, BOSS302S cars, etc.

Or, I am looking for data from people who have done the following mods:
  • FRPP GT500 fan shroud
  • Electric Water Pump
  • And any other mods that helped you
Thanks everyone :)
 

TMSBOSS

Spending my pension on car parts and track fees.
5,968
2,975
Exp. Type
HPDE
Exp. Level
5-10 Years
Illinois
Ducting!!!

Box in the area behind the grill to the radiator. Force as much air as possible through the radiator. Regardless of what car, generation etc. airflow through the radiator itself is key.
 

Mad Hatter

Gotta go Faster
3,611
2,136
Santiago, Chile
Before you reply saying you can run your car 10/10ths in 100°F ambient heat without issue, please consider that you are either not driving as hard as me, you aren't able to feel the car cut power, or you don't have the level of information that I have in regards to temperatures because you are relying on the stock gauge.

Here I think you are mixing things up a little. We can and do run races flat out in high temps all the time with considerably more HP (heat). Most of us don't trust the stock pcm gauges so that's why we install external gauges. Maybe you have a blockage in the radiator, pinched hose or faulty water pump or thermostat? A engine coolant temp of 240F is something I never had.... maybe you could use a steam turbine!!!

My oil temps at the track have gotten as high as 300F and still had no timing being pulled (its usually around 280F after about 20min flat out)

Your RWHP are pretty decent for a 4.6, what engine mods did you have??
 
23
11
CA
Some thing is not right for sure!! Maybe the water pump??? Or the water temp sensor is reading wrong? If you have SCT try logging the engine at the track.
Thanks for the replies Matt!

The tstat and water pump were both replaced about 2 years ago, and in normal driving the coolant systems stays at 190°F very nicely. With that being said, I think the gauge reads correctly. But my point is...even if the gauge is reading say...10-15°F off, I don't care. What I care about is the fact that the car cuts power. The cutting power is my main indicator here that I have a problem. The pinched hose and blocked radiator is something I haven't thought of. I'll take a look at the hoses today and see if there is anything obvious. Any way I could test to see if the radiator is bad other than dropping $500 on a new radiator? :(

And thank you, it's just bolt ons!
FRPP Intake
FRPP throttle body
UDP's
BBK Short tube headers
Lightweight flywheel
Good tune

Before I got the gauges installed, I would monitor temps with the SCT tuner, they would get up to about 230°F. But I was a much, much slower driver back then. lol
 

Mad Hatter

Gotta go Faster
3,611
2,136
Santiago, Chile
Oops!! I always get my C and F temps mixed up since we are full metric down here.... My pcm ECT temps get to 230F all the time. Maybe it could be a detonation problem thats pulling timing?? Some times it can even be something like a exhaust support that starts a false knock when it gets hot. At least with the Coyote PCM, not sure about the 4.6 though it probably is the same. Was haunted by false knocks at the track for quite a while. You can feel when the engine pulls a couple of degrees right away.

It might not be temperature related?
 
Why is it that nobody else has this problem?
Is there a chance you have air trapped in the system? Trapped air often impedes coolant flow, effectively resulting in an overheating condition. I know some engines/platforms are peskier than others when it comes to making sure the system is air-free when filling the coolant up. If you suspect that may be the case, you can use one of those 30-dollar radiator fill funnels (Lisle 24680, etc) and see if it bubbles out at all, or one of the vacuum systems that uses the venturi effect via an air compressor (also helps check for leaks in any hoses if the inHg doesn't hold steady).
 

Dave_W

Cones - not just for ice cream
272
268
Exp. Type
Autocross
Exp. Level
20+ Years
Connecticut
  • Edelbrock HV water Pump
  • UDP's
Just "thinking out loud" through this to come up with possibilities...

If you've got an underdrive pulley on the high-volume water pump (and/or crank), is the net adjusted flow from the water pump more or less than stock? Then again, if you're at higher rpm, the UDPs should be reducing the chance of impeller cavitation, if the impellers on the aftermarket pump are properly designed.

Have you tried a new ECT sensor? If the sensor is bad and reading high, maybe it could be triggering an ECU protection mode that's pulling the timing (and/or richening the mixture?). Just guessing.

Also, just trying to eliminate possibilities, are the hood louvers in a low-pressure area? If they're in a high(er)-pressure zone (like near the windsheild), they could actually be "backing up" the airflow through the radiator.
 

JDee

Ancient Racer
1,169
1,043
Exp. Type
W2W Racing
Exp. Level
20+ Years
halfway between Mosport and Shannonville
RaceLouvers RT hood vent pulled my temps from over 240 down to around 210. Nothing else added. Also took almost a second off my lap times. Best bang for the buck mod I ever did. There's a big difference in louver effectiveness across various brands and also where they are mounted.
 
23
11
CA
Thank You all for the replies,

The sensor for the autometer gauge is about 1yr old. I had the coolant system flushed and radiator installed by a shop that is very competent with late model mustangs (GTR high performance) about a year ago, but it definitely wouldn't hurt to check or give the system a burp. Is there any way that air bubbles could get into the system overtime?

The hood louvers themselves are custom units that Al @ racelouvers designed + built for me. I worked closely with Al in regards to the shape, size and position for maximum cooling. They are the maximum effort RX trim model

Al suspects that the edelbrock water pump is the culprit. I am 50/50 on it.

I called edelbrock this morning asking if they could provide me with a pump curve and/or a GPM rating at a certain RPM. They couldn't provide this info for me. Not very reassuring...

Some food for thought.....Below are some photos of some of water pump impellers available for my car. Interesting to see the differences in impeller design:

OEM style:
1623099033617.png

Edelbrock:
1623099049690.png

EMP Stewart "HP" water pump
1623099061103.png
 

Dave_W

Cones - not just for ice cream
272
268
Exp. Type
Autocross
Exp. Level
20+ Years
Connecticut
Are the vanes on the Edelbrock much further outboard than the other two compared to the edge with the o-ring, or is it for a different application? If you still have the stock pump, you could try putting it back in just to A/B test.
 
23
11
CA
Are the vanes on the Edelbrock much further outboard than the other two compared to the edge with the o-ring, or is it for a different application? If you still have the stock pump, you could try putting it back in just to A/B test.
Dave, I just ordered a motorcraft pump, should get here tomorrow. But from the pics it definitely appears to be that way. At this point I don't know what else could be causing such glaring issues given that under normal operating conditions the coolant system is fine.
 

Grant 302

basic and well known psychic
Edelbrock:
1623099049690.png
Wow. Looks like a pretty crappy design to me. Maybe it’s more suitable for drag race applications.
 
3,826
3,167
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Thank You all for the replies,

The sensor for the autometer gauge is about 1yr old. I had the coolant system flushed and radiator installed by a shop that is very competent with late model mustangs (GTR high performance) about a year ago, but it definitely wouldn't hurt to check or give the system a burp. Is there any way that air bubbles could get into the system overtime?

The hood louvers themselves are custom units that Al @ racelouvers designed + built for me. I worked closely with Al in regards to the shape, size and position for maximum cooling. They are the maximum effort RX trim model

Al suspects that the edelbrock water pump is the culprit. I am 50/50 on it.

I called edelbrock this morning asking if they could provide me with a pump curve and/or a GPM rating at a certain RPM. They couldn't provide this info for me. Not very reassuring...

Some food for thought.....Below are some photos of some of water pump impellers available for my car. Interesting to see the differences in impeller design:

OEM style:
View attachment 65718

Edelbrock:
View attachment 65719

EMP Stewart "HP" water pump
View attachment 65720
I made 700/700 with my super charged 3v stroker and a mizzere water pump worked perfectly on road courses. Good radiator, good ducting, hood vents and no ac condenser. I now have a gen 2 Coyote with that same combination and its flawless. Make sure there is a way for air bubbles to escape. Check my build thread for details.
 
3,826
3,167
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Hello everyone,

I am at a loss.

S197 mustang with a lowly 3v 4.6 making 315whp.

  • Fluidyne Radiator
  • Edelbrock HV water Pump
  • UDP's
  • Massive hood louvers
  • Ducted in radiator
  • Oil cooler
  • Fresh coolant w/Redline water wetter+distilled water

Yet, somehow, I can get the ECT's so hot in weather that is over 75°F, that the car will cut power (pull timing) on me. I have an autometer gauge that's taking coolant temperature in the engine block. Cruising, sits at 190°F. 7/10ths pace on track, reads around 220°F. A lap at Race pace, the gauge will hit 230°F, car will cut power. If I continue to stay in it, the car will get up to 240°F. I've never pushed it beyond that for obvious reasons.

Why is it that nobody else has this problem?

Keep in mind, my stock coolant gauge shows no difference between 190°F cruising and 240°F overheating. So before you answer, please read this Disclaimer, because it happens every time I ask this question:

Before you reply saying you can run your car 10/10ths in 100°F ambient heat without issue, please consider that you are either not driving as hard as me, you aren't able to feel the car cut power, or you don't have the level of information that I have in regards to temperatures because you are relying on the stock gauge.

So to summarize I'm looking for good data from people who genuinely have a car that they can beat on lap after lap in hot ambient temps. Maybe this is a totally unrealistic expectation? But I'd like to think it isn't considering the FR500S program, spec iron cars, BOSS302S cars, etc.

Or, I am looking for data from people who have done the following mods:
  • FRPP GT500 fan shroud
  • Electric Water Pump
  • And any other mods that helped you
Thanks everyone :)
Oops...I forgot, I also have that GT500 fan in the original post.
 
23
11
CA
Wow. Looks like a pretty crappy design to me. Maybe it’s more suitable for drag race applications.
I can't comment on if it's crappy or not, but I am worried about if it is intended for a drag application....ie more efficient at low RPM idling in the pits. I actually like the design.....with ships at least, a prop with more blades (ie the oem water pump) will be better at low RPM, but excessively cavitate at high RPM and increase drag. The edelbrock pump has the least "intrusive" design from what I can tell.
 

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