Track Time Limited due to High CHT

[GTP]

Yeah, I was about to say that maybe he's a really fast driver!

I run square setup of 275 MPSP4's as an intermediate driver, and everything gets really hot! I pack oven mitts just in case I have to take off a wheel. I log temps between sessions. But so far I've only run 20min sessions. Not sure the car will hold up for several 30min sessions.

I'm most concerned with A10 temp first, then diff, then oil. I really need a Mach1, lol.

Sponsored

 

[bnightstar]

And there’s nothing wrong with the car.

I’m asking a cheaply designed and built 460hp car to move nearly 4000lbs around a track at 95% of the car’s capability on 200Tw 305’s and I’m a half assed decent driver.

It makes an ass-pile of heat doing this so I’m having to figure out how to get the heat out.

Can I ask what Viscosity of oil and brand you are using. The Ford Racing School cars actually only have external oil cooler and the OEM radiator but they somehow run without issues for long sessions. They however use 5W50 oil instead of the recommended for road cars 5W20 or 5W30. With that in mind switching viscosity might help with cooling the CHT better.

 

[NeverSatisfied]

Can I ask what Viscosity of oil and brand you are using. The Ford Racing School cars actually only have external oil cooler and the OEM radiator but they somehow run without issues for long sessions. They however use 5W50 oil instead of the recommended for road cars 5W20 or 5W30. With that in mind switching viscosity might help with cooling the CHT better.

It’s something else I’ve been considering. My thought was get oil temps down to an acceptable level and stick with recommended oil—I change it after every 2 days of track time.

My car’s a ‘21 which calls for 5/30, but may switch to 5/40 this go around. Was hoping to avoid 5/50 with the cost jump!

Agreed that there’s got to be a correlation between all the fluid temps so pulling more heat out of the oil has to help ect some.

I have no idea how ford gets away with a factory radiator? I can lap my car all day now at 90-95% and it’ll stay cool. It’s that last little bit, where I’m beating the absolute snot out of it for more than 10+ minutes is where it starts to have issues.

 

[bnightstar]

It’s something else I’ve been considering. My thought was get oil temps down to an acceptable level and stick with recommended oil—I change it after every 2 days of track time.

My car’s a ‘21 which calls for 5/30, but may switch to 5/40 this go around. Was hoping to avoid 5/50 with the cost jump!

Agreed that there’s got to be a correlation between all the fluid temps so pulling more heat out of the oil has to help ect some.

I have no idea how ford gets away with a factory radiator? I can lap my car all day now at 90-95% and it’ll stay cool. It’s that last little bit, where I’m beating the absolute snot out of it for more than 10+ minutes is where it starts to have issues.

Yeah I know my laps are also limited because of that issue where car start pulling timing after 2 laps or so and I saw temps all the way up to 242F CHT. Which is something I'm not comfortable with especially since the ambient was only 80F or so. With that in mind I'm also looking for solutions kind of don't want to cut the hood and play with the front facia. Also Ford Racing school cars are racing school cars so maybe they are not driven as hard as our cars. I looked at Steeda 20 car and looks like they get away with oil cooler mounted behind the lower front facia instead of where the Mishimoto mounts. Also they reported that Mishimoto Oil Cooler is not working good enough for them (same reported Terry Fair when he was running a '18 on track). Tackaling CHT temps is my next priority so I guess I will go with Kenny Brown 3 pass radiator, better oil cooler maybe Aluminium Coolant tank (Steeda) and probably a racing hood.

 

[tosha]

kind of don't want to cut the hood and play with the front facia.

I have gotten a second hood from Marketplace for a reasonable price, did all the cutting and wrapped it. That way I can swap back to stock hood fairly quickly, and the cost was less than getting something like unpainted Vicrez GT500 hood.

 

[NeverSatisfied]

Yeah I know my laps are also limited because of that issue where car start pulling timing after 2 laps or so and I saw temps all the way up to 242F CHT. Which is something I'm not comfortable with especially since the ambient was only 80F or so. With that in mind I'm also looking for solutions kind of don't want to cut the hood and play with the front facia. Also Ford Racing school cars are racing school cars so maybe they are not driven as hard as our cars. I looked at Steeda 20 car and looks like they get away with oil cooler mounted behind the lower front facia instead of where the Mishimoto mounts. Also they reported that Mishimoto Oil Cooler is not working good enough for them (same reported Terry Fair when he was running a '18 on track). Tackaling CHT temps is my next priority so I guess I will go with Kenny Brown 3 pass radiator, better oil cooler maybe Aluminium Coolant tank (Steeda) and probably a racing hood.

I definitely would go bigger than the mishimoto radiator in hindsight.

And recommend a MONSTER oil cooler. I don’t see anything off the shelf that looks big enough. My Setrab 25 row was not enough. I’m hopeful this 50 row will do the trick

With full gauges now I’m just not comfortable seeing ect go 210+ and oil creep over 250 which was happening for me once I exceeded 225 CHT.

I have yet to test my 50 row oil cooler, gutted shroud, running mostly distilled water and upped the oil wt. to see if that does it. Should be on track in another couple weeks. I gotta be close to the finish line. Will report back.

 

[mkcotton]

I am starting to have these heat issues as well. I was hoping that those that have resolved or greatly improved their temps issues could recommend the better of the two below. I already have an aluminum cooling tank (which helps about 3-5 degrees). Looking for before and after temps, installation ease and durability Thx!

Mishimoto Radiator: https://www.americanmuscle.com/mishimoto-perf-aluminum-radiator-1517gt.html

CSF Radiator: https://www.americanmuscle.com/csf-...h-performance-all-aluminum-radiator-7073.html

 

[nbjeeptj]

I went with the earls equivalent of a Setrab series9 60 row. It is the one designed to work with the Watson racing radiator close out. Since I am piecing this oil cooler setup together myself with no instructions I am wandering if flow direction will matter (oil in top out bottom, or other way around), and is it necessary to bleed air out or prime the setup, once its installed. It just seams that air could get trapped in this system pretty easy and I cant see a way to bleed it out. I may be way overthinking this but I do not want to starve the engine for oil on startup or send a big bubble of air to a bearing at a unexpected time.

 

[NeverSatisfied]

I went with the earls equivalent of a Setrab series9 60 row. It is the one designed to work with the Watson racing radiator close out. Since I am piecing this oil cooler setup together myself with no instructions I am wandering if flow direction will matter (oil in top out bottom, or other way around), and is it necessary to bleed air out or prime the setup, once its installed. It just seams that air could get trapped in this system pretty easy and I cant see a way to bleed it out. I may be way overthinking this but I do not want to starve the engine for oil on startup or send a big bubble of air to a bearing at a unexpected time.

Interwebs typically recommend both in and out are on the top to avoid air pockets and drain back which makes sense in my head.

Despite this, I ran your orientation for years trouble free in a Miata feeding in from the bottom and out from the top.

Any time i crack the oil cooler open, I pull the coil plugs and crank it quite a bit. In your situation on first install, I'd prefill the oil cooler best I could through the "outlet" before priming.

I think you're on the way to trouble free lapping with your setup.

 

[Scootsmcgreggor]

Interwebs typically recommend both in and out are on the top to avoid air pockets and drain back which makes sense in my head.

Despite this, I ran your orientation for years trouble free in a Miata feeding in from the bottom and out from the top.

Any time i crack the oil cooler open, I pull the coil plugs and crank it quite a bit. In your situation on first install, I'd prefill the oil cooler best I could through the "outlet" before priming.

I think you're on the way to trouble free lapping with your setup.

Mine are on the side and I have no drain back issues FWIW.

 

[67Fast_V]

I went with the earls equivalent of a Setrab series9 60 row. It is the one designed to work with the Watson racing radiator close out. Since I am piecing this oil cooler setup together myself with no instructions I am wandering if flow direction will matter (oil in top out bottom, or other way around), and is it necessary to bleed air out or prime the setup, once its installed. It just seams that air could get trapped in this system pretty easy and I cant see a way to bleed it out. I may be way overthinking this but I do not want to starve the engine for oil on startup or send a big bubble of air to a bearing at a unexpected time.

Looking good . My only suggestion is to close-off the axial gap between the oil cooler and the radiator around the perimeter of the oil cooler. Otherwise, the air coming through the grille will go around the oil cooler (through the gap) and not through the fins of the oil cooler.

Certainly some air will go through the oil cooler but you will be losing a good amount as the flow will by-pass and fill the gap downstream. And what this will do is make the oil cooler much less effective. What you want to do is give the air only one way to go ... and that is ... through the oil cooler and then through the radiator.

Would suggest some side "blocking" panels made of aluminum or plastic sheets on all 4 sides to close-off that gap. Just make sure whatever might contact the radiator fins, that it's a soft seal strip and doesn't have a hard edge. Or I guess you could leave a small axial gap between the side "blocking" panels and the radiator fins.

 

[67Fast_V]

I am starting to have these heat issues as well. I was hoping that those that have resolved or greatly improved their temps issues could recommend the better of the two below. I already have an aluminum cooling tank (which helps about 3-5 degrees). Looking for before and after temps, installation ease and durability Thx!

Mishimoto Radiator: https://www.americanmuscle.com/mishimoto-perf-aluminum-radiator-1517gt.html

CSF Radiator: https://www.americanmuscle.com/csf-...h-performance-all-aluminum-radiator-7073.html

It appears that I may be in the minority here, but the cooling issues with these GTs is not caused by the radiator size. The PP1 radiator is actually pretty big for a 460 hp engine. I have compared it to other much higher HP engines and Ford did well to spec out a radiator w/ a lot of surface area.

In my opinion, the cooling issue with these GT's from the factory is 80-90% related to the lack of airflow through the radiator. The radiator surface area is fine. My track data pretty much proves this.

All of my mods to date have been changes to drive more air through the radiator. And these changes have resulted in a significant reduction in CHT, all conditions equivalent. I have not removed/replaced any of the factory main cooling components. Still running stock rad, oil cooler, and trans cooler. I have modified the OEM fan shroud, sealed the radiator perimeter, and installed a hood vent. And also installed a 170F t-stat, removed some anti-freeze, and added some water wetter. However those 3 items have no or very minor impact to cooling under track conditions.

I have a track event this Thurs and hope to test out my 95% sealed radiator. I say hope, cus I need 2-3 back to back flat out laps to prove-out the modification. The traffic almost always hinders me from doing this. And my inconsistent driving doesn't help. I expect CHT=238-239F max. Previous max was 247F. So about a 8-9F reduction ... per my calculations going from ~50% sealed to 95% sealed. But let's see how it does on the track. Going to be blistering hot ambient temp (92+F). maybe 100F on the track.

If this works as intended, then I will install my modified grille and that should take care of the CHT problem for my application (HPDE, 20-25 min sessions, A10, 200 tread, stock hp, 3rd - 7th gear, max rpm shifts). The only uncertainty is whether I can get the calc oil temp below the 280F threshold ... w/ the factory oil cooler. I think yes, but gotta get the data. Who knows what Ford is doing behind the seen w/ that calculation.

 

[bnightstar]

I have a track event this Thurs and hope to test out my 95% sealed radiator. I say hope, cus I need 2-3 back to back flat out laps to prove-out the modification. The traffic almost always hinders me from doing this. And my inconsistent driving doesn't help. I expect CHT=238-239F max. Previous max was 247F. So about a 8-9F reduction ... per my calculations going from ~50% sealed to 95% sealed. But let's see how it does on the track. Going to be blistering hot ambient temp (92+F). maybe 100F on the track.

So if I'm seeing 242F max CHT there is nothing to worry about ?

 

[NeverSatisfied]

So if I'm seeing 242F max CHT there is nothing to worry about ?

I think you’re really pushing it at those temps.

From what I’m seeing at 10-20f ect/cht delta, 245 cht has you at 230F+ ect. Oil temp at 280f+ is really pushing things too.

I’m my ‘21 Ford agrees with me in that any extended time at 235+ Cht and the car is pulling timing. It’s subtle. there’s no dash warnings or rpm limit, but she’s not giving me all 460 horses.

I think another variable in temp problems from car to car we don’t have a great yardstick for is lap times. From my experience, even 1 second of delta in lap times makes a big difference in fluid temps.

 

[bnightstar]

I think you’re really pushing it at those temps.

From what I’m seeing at 10-20f ect/cht delta, 245 cht has you at 230F+ ect. Oil temp at 280f+ is really pushing things too.

I’m my ‘21 Ford agrees with me in that any extended time at 235+ Cht and the car is pulling timing. It’s subtle. there’s no dash warnings or rpm limit, but she’s not giving me all 460 horses.

I think another variable in temp problems from car to car we don’t have a great yardstick for is lap times. From my experience, even 1 second of delta in lap times makes a big difference in fluid temps.

I never seen the oil temps even into yellow though. ECT's were up to 224F according to track addict logging. But the CHT's was high at 242 cht. I didn't feel pulled timing and improved my times a lot this time out. But I still think that better cooling is obviously needed.

Sponsored