Cooling question on a GT, N/A

[Sirl]

Car is a 2000 GT, N/A, only pushing 260/300.
95% track car, about 6 track weekends a year, down here in S. Florida.

Water temp is hitting about 220+ after about 5 hard laps.

160 t-stat
Mishimoto alum. radiator
Running water and water wetter only
Termi bumper cover.
Still have the little air dam underneath
I had the bottom of the bumper cover to the radiator covered/boxed. Tried it both ways this weekend with it on and off, did not make a difference.

Still have A/C in the car as well.

Here's the question, does anyone have any idea how much cooling the a/c condenser is robbing from the car?? Is it blocking a lot of airflow?
If I lose the condenser, will it run cooler??

Runs fine on the street, about 180ish in hot traffic

I dont know what else to try, although I have a GT500 hood vent, but thats a last resort.

TIA,

 

[wheelhopper]

If it is 90% track you should ditch the AC regardless. Lets the air flow a little better and one less item the motor has to work to turn.

How about an oil cooler? I have that on my fox body and it is rare that my water temp is above 190 and that my oil is above 230.

 

[NELCO]

If it is 90% track you should ditch the AC regardless. Lets the air flow a little better and one less item the motor has to work to turn.

How about an oil cooler? I have that on my fox body and it is rare that my water temp is above 190 and that my oil is above 230.

Dead On!!!!!!

Nelco

 

[racebronco2]

If it is 90% track you should ditch the AC regardless. Lets the air flow a little better and one less item the motor has to work to turn.

How about an oil cooler? I have that on my fox body and it is rare that my water temp is above 190 and that my oil is above 230.

Do you drive to and from the track in your car?
One thing about the a/c is it sure feels nice and refreshing on the drive home in the heat of the summer. Yes it does allow the airflow a little better but is it really worth getting rid of if you drive the car in the summer? Not for me it isn't. The a/c compressor takes very little hp to turn when it is not engaged.

The problem with many cars that are driven on the street and the track is they run too hot. I know countless people running foxbodies, sn95's and new edge mustangs. The problem is not enough airflow.

My open track cobra at about 550rwhp runs about 220* in temps around 100*. I think most of the is due to the real heat extractor hood. It used to run about 205 before i installed 2 heat exchangers.

 

[wheelhopper]

Heck no, I don't drive my car to the track. Never have. The closest track to me is 2 hours away and I have always been fortunate enough to have a car trailer and truck even before I started OT. I don't want to take the risk of being 5 hours from home, which usually I am, and having a car issue then having to make it home.

In any event I don't see why a specialized hood or any extreme measures would be needed to control heat on a 260hp car. That is what my car makes and I play cat and mouse with a friend of mine, who dyno's near exact what I do in a 2002 GT. We drive plenty hard turning 2:18-2:19 times at VIR. He has no aftermarket parts for cooling at all and does not have any heat issues. He has talked about getting a larger radiator, but that is it. Since Sirl already has that I would do the next easy cheap thing. I think you would be fine after that.

 

[Sirl]

Well, I do drive the car to Homestead and Palm Beach, but trailer it to Sebring.

Occasional dinner with the wife, and car shows. I LOVE having the ac down here and really dont want to get rid of it.
Like I said, I do have a GT500 hood scoop, looking for a shitty hood to try it out on.
I cant imagine how hot my oil is getting.. probably to hot.
So, your thinking... either losing the a/c and/or, doing the heat extractor hood deal..??

I was looking at the a/c condenser yesterday, its not like there is massive air passages.. pretty narrow, I'm sure air is not flowing that great.. plus, at 100k miles, some fins are bent down, and some junk between the fins.

Hard being a "tweener"... half street half track...

Oh, I was running with no t-stat, but was recommended to put a 160 in, thinking the water is not having a chance to cool down... I put the 160 in, and no change either.

Guess I'm at a crossroads here.

By the way, what oil cooler would you recommend??

Also been thinking about the MM oil filter relocation kit, and maybe an oil cooler at the same time.

 

[N/Angel]

I'm running my car N/A at the moment and I only hit 206 degrees coolant temp in heavy traffic when the car doesn't move. Drops quickly once the fan comes on.
On the track or on long Autobahn WOT runs my coolant is never above 180.
I have a LFP race radiator, no thermostat and an oil cooler placed on the driverside opening of the Terminator bumper. Separating the coolant and oil makes the difference I believe.

 

[Sirl]

Angel, main question is, Do you have the A/C Condenser still, in front of the radiator??

I'm starting to think more and more that the a/c condeser is not letting enough air flow. its 13 years old, the fins are about as wide apart as a credit card, maybe.

Think i'm gonna remove that, and see if it helps.

Thanks for all your input.

 

[N/Angel]

no, no A/C, sorry forgot to mention.

 

[racebronco2]

Angel, main question is, Do you have the A/C Condenser still, in front of the radiator??

I'm starting to think more and more that the a/c condeser is not letting enough air flow. its 13 years old, the fins are about as wide apart as a credit card, maybe.

Think i'm gonna remove that, and see if it helps.

Thanks for all your input.

It would help out if you did clean out the a/c condenser and radiator. It's probably full of all sorts of things.

wheelhopper runs on high speed tracks where he never uses 2nd gear, the track where i live almost all of them 2nd gear is needed. The difference is the higher the speed the more air is forced thru the radiator. If you are using second gear like me the slowest turn is 35mph, not a whole lot of air is being forced thru the radiator at those speeds. I would think that is why he hasn't had any cooling issues with his cobra or his track car either that or he drives like an old ladyoke:. Just kidding there. But honestly lower speed tracks are going to need more cooling than higher speed tracks.

I just checked and at willow springs if you are doing a mid 1:30's the average speed is only 93 mph. At this track the front straight a 260hp mustang is doing about 130mph.

At AAA speedway a STR1 car does low 1:40's and hitting close to 160mph on the front staight is only averaging 95mph. A 260hp mustang running a little less than 2 minutes is averaging 85mph but speeds on the front straight are closer to 135mph.

At AAA speedway without the front straight times are in the 1:15 range and average speed is around 78mph.

Wheelhopper the tracks you run at what are the average times and speeds?

 

[racebronco2]

I have done a lot of datalogging over the years. What i have found is that the engine temps rise as the rpms increase, after a shift they continue to rise a little more and they actually start to decrease in the mid rpm range , start to rise and again continue til after the shift etc. If you are on a track the you are only using 2 gears compared to 4 gears, the temps on the car using 4 gears are going to run hotter. Why because you are using more hp over all.

 

[Sirl]

Thanks for all the info!
Homestead is a Roval, 2nd, 3rd, 4th each to redline, then, back to 2nd, etc. etc.

I decided, the condenser is coming out. It may be some time, but I'll post up the results.

fyi, the radiator is fairly new, 6-8 months. condenser, stock, never cleaned, 13 years and 101k miles.


Maybe a silly question, but is it possible to run a smaller condenser?? like half the size?? or is that ridiculous?

 

[sn95Cobrakai]

Not to hijack thread, but I feel your pain.
I have heating issues as well. I have A/C, running OEM Thermostat, Running 70/30% mix water/antifreeze with water wetter, 3-core Fluidyne radiator, stock cobra oil cooler, and stock Air Dam. I have a 98 cobra Making around 300hp
I am seeing temps average 220* and going up past 240* before I have to pull off at thee track. On the street it is around 200* and goes to 230* in traffic.

I am not sure if its my water/coolant mix, or thermostat, or what that is causing the high temps but my friends high HP motors don't have these problems. So I am definitely tuning in to see if they can help resolve your problem and hopefully get some ideas to remedy mine.

 

[racebronco2]

Thanks for all the info!
Homestead is a Roval, 2nd, 3rd, 4th each to redline, then, back to 2nd, etc. etc.

I decided, the condenser is coming out. It may be some time, but I'll post up the results.

fyi, the radiator is fairly new, 6-8 months. condenser, stock, never cleaned, 13 years and 101k miles.

Maybe a silly question, but is it possible to run a smaller condenser?? like half the size?? or is that ridiculous?

Not to hijack thread, but I feel your pain.
I have heating issues as well. I have A/C, running OEM Thermostat, Running 70/30% mix water/antifreeze with water wetter, 3-core Fluidyne radiator, stock cobra oil cooler, and stock Air Dam. I have a 98 cobra Making around 300hp
I am seeing temps average 220* and going up past 240* before I have to pull off at thee track. On the street it is around 200* and goes to 230* in traffic.

I am not sure if its my water/coolant mix, or thermostat, or what that is causing the high temps but my friends high HP motors don't have these problems. So I am definitely tuning in to see if they can help resolve your problem and hopefully get some ideas to remedy mine.

Maybe wheelhopper can chime in. I would bet that he winds out 3rd and maybe 4th. His speeds are higher therefor he would have more cooling taking place. The problem is at the slower speeds.

sn95Cobrakai, is the track you run is it a slower or faster track? What is the average speed?

Sirl and sn95Cobrakai, take a flashlight and shine it thru your radiator from the engine side to the front of the vehicle. If it is partially clogged you will be able to see it. My observation is that it's really bad where the grill opening and bumper opening are located. It's really clean where they is no direct airflow.

Downsizing the a/c condenser will not keep the a/c cool enough inside the cab. I'm not sure if they even make any 1/2 the size.

 

[wheelhopper]

Just got back from VIR. I use 3rd, 4th, and have a useable 5th gear.

I have run a fair number of tracks and different configurations. The shortest was VIR South at 1.6 miles with one 180 degree turn. I doubt I'll do that track ever again and don't usually look to do tracks less than 2 miles long. I can never remember using 2nd gear. I am sure I tried it a number of times but found it just to low and I would have to up shift so soon it was not worth using. I find the same with the students I teach, unless they are turtling and then I sip my coffee while they cruise around the track.

I don't know what the average speeds and times are at the tracks I run. I just try to run as fast as I can.

 

[N/Angel]

on a side note, not sure if useful and proven information... a while back in the Terminator section there was the discussion about the Mishimoto radiator being less effective then the OEM unit.
I saw a Mishimoto unit at the shop this year and compared to my LFP it was quite a bit smaller/thinner. Not sure if size really matters when it comes to radiators, but I always thought so :shrug:

 

[racebronco2]

on a side note, not sure if useful and proven information... a while back in the Terminator section there was the discussion about the Mishimoto radiator being less effective then the OEM unit.
I saw a Mishimoto unit at the shop this year and compared to my LFP it was quite a bit smaller/thinner. Not sure if size really matters when it comes to radiators, but I always thought so :shrug:

What helps more is more surface area. Radiator thickness is less effective.

 

[racebronco2]

If your on a track that uses mostly 3rd and 4th compared to 2nd,3rd and 4th you are using alot less hp over all. Less hp means less heat equals cars running cooler. If you have a 260 hp mustang and use only 3rd and 4th your average hp will be around 210hp for both gears combined will be 420hp if you are running 3000-5500rpm. If you are using 2nd, 3rd and 4th your combined hp will be 630hp if you are using 3000-5500rpm. So you can see that you will generate 50% more heat than if you are using only 3rd and 4th. That's why you have heard (mostly when discussing Terminators on track ) to shift earlier and to the next higher gear on the straights. Why? Because you are not using as much hp. Running on the autoban at 150mph barely into boost does not generate nearly as much heat when you are wot in second, 3rd and 4th gear. In fact you have alot more airflow at those speeds.

 

[wheelhopper]

^I just got a chuckle from reading that.

An engine makes horsepower at a given RPM regardless of what gear it is in. If it makes 260hp at 5500rpm, then regardless of whether it is in 2nd, 3rd, or 4th it is making that power. An engine will run cooler in 3rd gear vs 2nd, as long as it is installed in a way that it is receiving additional cooling due to increased air flow over the radiator compared to motor siting still making power. Such as on a dyno run.

Also the supercharged car running at 150mph on the Autobahn is making less boost due to the rpm of the motor and supercharger based on the final drive gear the car is in.

 

[racebronco2]

^I just got a chuckle from reading that.

An engine makes horsepower at a given RPM regardless of what gear it is in. If it makes 260hp at 5500rpm, then regardless of whether it is in 2nd, 3rd, or 4th it is making that power. An engine will run cooler in 3rd gear vs 2nd, as long as it is installed in a way that it is receiving additional cooling due to increased air flow over the radiator compared to motor siting still making power. Such as on a dyno run.

Also the supercharged car running at 150mph on the Autobahn is making less boost due to the rpm of the motor and supercharger based on the final drive gear the car is in.

I was talking about the average hp for each gear 3000-5500rpm. I think i know hp at 5500rpm is the same no matter what gear you are in. If you are using more gears you are going to need more cooling because you will be at peak hp more often. Peak hp is what creates the most heat. Being in second gear will cause the temps to rise faster because you are at peak hp so much faster than 3rd or 4th gear. The air entering the grill opening is going much slower at 60mph in second then it is say at 95mph in third.

N/ANGEL had said in a previous post something to the effect that why can't her car go any faster on the autoban. She didn't want to push her car any higher rpms, she didn't want to hurt her car. Therefor it wasn't wot just maintaining the speed which wouldn't hardly be into boost.

Once the driver is up to speed they are making less boost because the driver is just maintaining the speed not still at wot. With 3.55's and a blower it's capable of speeds alot higher then 150mph.