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Track Time Limited due to High CHT

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67Fast_V

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Thanks, I look at it more as multiple approaches complimenting each other, rather then making choices. I don't want to mess with ducting and opening up the grilles before I add a way to extract all the additional air that will be coming in (hood buffering and lift), so adding louvers seems to be a good first step. I will have an opportunity to test it first and then add ducting and test again. Would be interesting to see progression. As long as I can cut up to 10 degrees just with louvers, that would be great.

My goals for the reference - I have manual GT with PP1, so no issues with transmission oil heating up everything else. However, I also have a roush/fp supercharger, which is adding quite a lot of heat. I don't have issues short shifting, as I'm not chasing any lap records and have enough torque at any point in rev range. I also live up north, so I don't have to deal with very high ambients. In my recent HPDE event, the first day it was 50F and raining almost all day, next day it went up to 65F with sun. Car did great, especially on first day I don't think I saw CHT's going over 210F. On a second day, it started climbing towards 225F, but 1-2 cooldown laps per session kept it in check. As long as I can stay within 230F range during warmer days, I would be happy with the result.
Interesting project. Cool to see lots of different applications. The SC will certainly make cooling a challenge if you push hard. On the hood vent, I would not expect 10 deg F reduction ... more like 4-5F. However, the more leaks there are (and bigger grille if you go in that direction), the more cooling benefit you will get from the hood vent.

In practice, it's difficult to determine the exact benefits of cooling mods because of inconsistent conditions. Max temp is driven my max heat load and that will vary quite significantly from lap to lap and day to day. I have found that unless I get at least 2 laps back to back, both at full effort (hammered), I don't know the max temps.

There has been many of my sessions where I see 230-235F type max CHT but this is not a true indication of where I stand, unfortunately. For example it took the 4th session at my last event to get 3 consecutive laps at full bore. I was feeling good about the benefits of my hood vent up until that point. Seeing temps in the 230F range and a nice reduction on the tranny temps as well. And then the reality set in and got reminded of the physics. What an awesome learning process, though. Cheers.
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Interesting project. Cool to see lots of different applications. The SC will certainly make cooling a challenge if you push hard. On the hood vent, I would not expect 10 deg F reduction ... more like 4-5F. However, the more leaks there are (and bigger grille if you go in that direction), the more cooling benefit you will get from the hood vent.

In practice, it's difficult to determine the exact benefits of cooling mods because of inconsistent conditions. Max temp is driven my max heat load and that will vary quite significantly from lap to lap and day to day. I have found that unless I get at least 2 laps back to back, both at full effort (hammered), I don't know the max temps.

There has been many of my sessions where I see 230-235F type max CHT but this is not a true indication of where I stand, unfortunately. For example it took the 4th session at my last event to get 3 consecutive laps at full bore. I was feeling good about the benefits of my hood vent up until that point. Seeing temps in the 230F range and a nice reduction on the tranny temps as well. And then the reality set in and got reminded of the physics. What an awesome learning process, though. Cheers.
Exactly. The difference between 50F/raining vs 65F/sunshine is 15 degrees difference in CHT in exactly same car setup and driving skill level. That's why I feel that any heat extraction would bring a big benefit. Even if it's 5 degrees reduction, it's great as long as it's consistent. Ducting should bring another big improvement and adding sprinklers from windshield washer idea should make it pretty reliable for my case. SC does add a lot of heat, but then I can shift at 6k and still be faster than majority of other cars at the straights. At least until that ZL1 or 911 turbo shows up šŸ˜„
 

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I'm going to repeat my warnings. 230+ is cooking your engine. It should never see over 200 in anger and proper operating temp is roughly 185 F. The stock rads are completely undersized. Just because you're not in limp mode doesn't mean you're not overheating.
 
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I'm going to repeat my warnings. 230+ is cooking your engine. It should never see over 200 in anger and proper operating temp is roughly 185 F. The stock rads are completely undersized. Just because you're not in limp mode doesn't mean you're not overheating.
Thanks for the warning. Just a few quick thoughts ... (1) The stock t-stat puts CHT at 190-205F just trying around town in traffic. (2) The factory fans don't come on until CHT =212F (the low setting, high setting is 223F), ... unless the AC is on. And (3) take a look at the factory PP1 radiator geometry and compare that to the geometry of other radiators in high performance cars. I think you might be impressed. Cheers.
 

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(Keeping this great discussion going)

What are everyone's thoughts between going just with racelouvers rx center vent, or rx center + rt side hood vents? Are sides really worth it or center vent would do most of the work anyways?
I'm on the very edge of what it takes to keep a 6MT GT cool if you're going to really bang on it and you're running 305mm 200TW tires at the track. If racing, running RComps, or trying to lap in Texas at 105F ambient, I'd probably be back to the drawing board.

Just ran Mid-O at 70F ambient saw a max CHT of 210-213 in the slower high RPM sections and it drops to 206-208 at the end of the longer straights.

I added cooling items one at a time until I got there, but I did add all the race louvers at once.

The recipe I followed to get there was Mishi Rad, 90-95% boxed in, Race Louvers, Setrab 6 series 25 row oil cooler spaced ~1/8" off the condenser.
 

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I'm going to repeat my warnings. 230+ is cooking your engine. It should never see over 200 in anger and proper operating temp is roughly 185 F. The stock rads are completely undersized. Just because you're not in limp mode doesn't mean you're not overheating.
If you refer to CHT's, then I'm not sure how it's even possible, to be honest. 195-200F is the normal temp for me when I'm cruising on highway in 6th. I see 185F only when engine is not fully warmed up. The moment I find myself in traffic in a relatively hot day, temps start climbing up above 210F. The fans don't even kick in until over 215F. If you talk about coolant temps, then it's a different case of course.
 
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I'm on the very edge of what it takes to keep a 6MT GT cool if you're going to really bang on it and you're running 305mm 200TW tires at the track. If racing, running RComps, or trying to lap in Texas at 105F ambient, I'd probably be back to the drawing board.

Just ran Mid-O at 70F ambient saw a max CHT of 210-213 in the slower high RPM sections and it drops to 206-208 at the end of the longer straights.

I added cooling items one at a time until I got there, but I did add all the race louvers at once.

The recipe I followed to get there was Mishi Rad, 90-95% boxed in, Race Louvers, Setrab 6 series 25 row oil cooler spaced ~1/8" off the condenser.
Thanks for sharing. Lots of different approaches. Your temps are great as far as I'm concerned. I'm running 305/ RE71r's.

Removing the oil heat load from the coolant will certainly help. As mentioned above, I'm going to try to keep the factory oil cooler. Based on my data/experience, I expect to be able to do it.

How are your max oil temps w/ that Setrab?
 

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Thanks for sharing. Lots of different approaches. Your temps are great as far as I'm concerned. I'm running 305/ RE71r's.

Removing the oil heat load from the coolant will certainly help. As mentioned above, I'm going to try to keep the factory oil cooler. Based on my data/experience, I expect to be able to do it.

How are your max oil temps w/ that Setrab?
Fair warning--I could not flog the car until I separated the oil cooling. I was stuck short shifting at 6-6500RPM at reasonable ambient temps or it would start to derate.

I have not put a separate gauge on the oil cooling yet (I know that's a terrible idea), but separating oil from the coolant was the final fix to get CHT down and keep calculated oil temps out of the derate zone.

I'm going to try and get gauges on the diff, trans, engine oil before I head to Nelsons next weekend.
 

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Thanks for the warning. Just a few quick thoughts ... (1) The stock t-stat puts CHT at 190-205F just trying around town in traffic. (2) The factory fans don't come on until CHT =212F (the low setting, high setting is 223F), ... unless the AC is on. And (3) take a look at the factory PP1 radiator geometry and compare that to the geometry of other radiators in high performance cars. I think you might be impressed. Cheers.
1- Yep, the thermostat is the first thing to change. A 160* thermostat is fully open by 175.

2- Fans don't do much at speed. They are for traffic.

3- It's not a matter of being impressed with a rad. It has to keep the car at the right temperature. If it can't, then we need to find one that can.

I don't necessarily have the blueprint of how to fix the problem (I shared some ideas earlier), but I do know the engine temperatures which many people seem ok with, I am not. At the very least, you're losing significant power, flirting with big bearing clearances and making the ECU work to avoid spark knock.
 
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Fair warning--I could not flog the car until I separated the oil cooling. I was stuck short shifting at 6-6500RPM at reasonable ambient temps or it would start to derate.

I have not put a separate gauge on the oil cooling yet (I know that's a terrible idea), but separating oil from the coolant was the final fix to get CHT down and keep calculated oil temps out of the derate zone.

I'm going to try and get gauges on the diff, trans, engine oil before I head to Nelsons next weekend.
There is always a near infinite amt of work to do. Well at least you have an easy port to access for the oil temp w/ your Setrab oil cooler. I looked for a location to check oil temps w/ the stock system and couldn't find anywhere to tap into. If someone knows where a oil temp sensor could be install in the stock system, please chime in.

Curious based on your experience, at what temperature does this de-rate occur and what is the mechanism? I assume it will pull timing and/or enrichen but when and how much?

I finally pulled my stock tune file yesterday to start the process of getting familiar w/ the engine control. What a nightmare to try to sort. Going to take awhile. Zero experience.

So far I noticed the WOT lambda is set to 0.82. Seem pretty rich to me. Also I noticed that several tables have engine coolant temp (ECT) as a control input ... and not CHT. But I'm not sure if it's actually using ECT, though. If someone knows for sure, please chime in. Note that at higher temps/load, ECT is about 13F lower than CHT. Cruising around town, they are identical. Only once CHT climbs, they start to deviate.
 

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There is always a near infinite amt of work to do. Well at least you have an easy port to access for the oil temp w/ your Setrab oil cooler. I looked for a location to check oil temps w/ the stock system and couldn't find anywhere to tap into. If someone knows where a oil temp sensor could be install in the stock system, please chime in.

Curious based on your experience, at what temperature does this de-rate occur and what is the mechanism? I assume it will pull timing and/or enrichen but when and how much?

I finally pulled my stock tune file yesterday to start the process of getting familiar w/ the engine control. What a nightmare to try to sort. Going to take awhile. Zero experience.

So far I noticed the WOT lambda is set to 0.82. Seem pretty rich to me. Also I noticed that several tables have engine coolant temp (ECT) as a control input ... and not CHT. But I'm not sure if it's actually using ECT, though. If someone knows for sure, please chime in. Note that at higher temps/load, ECT is about 13F lower than CHT. Cruising around town, they are identical. Only once CHT climbs, they start to deviate.
Iā€™m not sure what ect or cht triggers it but it starts pulling timing as the calculated oil temp gets from the yellow to the red.

I like the Setrab sandwich adapter for the oil because I run straight m22 oring to -10an with no fitting restrictions. Downside is thereā€™s no ports on the Setrab sandwich plate.

I did find an extension for the oem oil pressure switch that has two extra ports on it that I plan to use to tap pressure and temp. Not sure I like the idea of three sensors hanging off an extension though.
 

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How do you guys retrieve the inferred oil temp? I cannot seem to find a PID for it that works through my obd2 connector, and I don't have a gauge for it in the digital dash.
 
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Iā€™m not sure what ect or cht triggers it but it starts pulling timing as the calculated oil temp gets from the yellow to the red.

I like the Setrab sandwich adapter for the oil because I run straight m22 oring to -10an with no fitting restrictions. Downside is thereā€™s no ports on the Setrab sandwich plate.

I did find an extension for the oem oil pressure switch that has two extra ports on it that I plan to use to tap pressure and temp. Not sure I like the idea of three sensors hanging off an extension though.
Good to know, thanks. My oil temp has been on green-yellow edge. I will go hunting for the oil pressure sensor, see what it looks like. If you or someone has a photo, that would be helpful too.
 

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Good to know, thanks. My oil temp has been on green-yellow edge. I will go hunting for the oil pressure sensor, see what it looks like. If you or someone has a photo, that would be helpful too.
On the gen three itā€™s berries behind alternator above oil filter
 
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67Fast_V

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How do you guys retrieve the inferred oil temp? I cannot seem to find a PID for it that works through my obd2 connector, and I don't have a gauge for it in the digital dash.
I was bummed to find out as well that there is no PID available that HPtuners device will pull. The only way to look at the oil temp is on the center console display. You will see it read Normal or Warm, etc. Then just click on it and it will display a "color" graph.

Ford has indicated what the color ranges are. The edge of green yellow is 280F . The edge of yellow red is 296F. At the end of the session, basically at the start of the cool down lap, I toggle over to see where the temp lies. Then I write down where the needle was positioned when I get back to the pits. Terrible method, but that's all I have at the moment.
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