Foot to floor, but data sez big "accel pedal %" dropoff

[ZDan]

For me, for my usage, option 1, by far.

The tuner's 275F limit is appropriately conservative, presumably assuming 0w20 weight oil. Personally I haven't seen anything to suggest that 275F should be a problem running good synthetic 30-weight.

FWIW I never encountered any factory oil temp cutoff running the same oil temps. I've read that there may be one around 300F?

Originally Posted by FR-S2GT86

So in your situation, what do you think would be the better fix out of these two examples?

1) Increase the thermal safety limit so that the ECU can't limit the power output of the engine when the oil reaches the original temperature setpoint,

or

2) Install an oil cooler so that the oil temperature doesn't reach the original thermal limit in the first place.

[Goingnowherefast]

Originally Posted by ZDan

Personally I haven't seen anything to suggest that 275F should be a problem running good synthetic 30-weight.

But again, it's not the oil breaking down that's the danger here. It's the worry that the viscosity of the oil drops low enough that it's unable to provide adequate lubrication to the bearings. I'd recommend sending your oil out to Blackstone for analysis if you plan on not running and oil cooler.

[FR-S2GT86]

Originally Posted by ZDan

For me, for my usage, option 1, by far.

The tuner's 275F limit is appropriately conservative, presumably assuming 0w20 weight oil. Personally I haven't seen anything to suggest that 275F should be a problem running good synthetic 30-weight.

FWIW I never encountered any factory oil temp cutoff running the same oil temps. I've read that there may be one around 300F?

Just out of curiosity, did you verify with your tuner what the stock temperature limit is, whether it be 300 degrees like you've read somewhere, or some other value, and that he specifically lowered this limit in his tune?

If he indeed lowered the limit, then I agree with you that you should be fine in the short term. However, if you're regularly tracking your car, I agree with @Kelse92 in that for the overall life of your engine, you should still install an oil cooler. If I were in your shoes and in the same situation, I would.

[DarkSunrise]

Originally Posted by ZDan

FWIW I never encountered any factory oil temp cutoff running the same oil temps. I've read that there may be one around 300F?

Just curious if anyone has actually seen the oil temp based compensation tables in their tunes. In romraider Ive seen and played around with the coolant and IAT based timing compensation tables with some success but I’ve never found any tables that pull timing based on oil temps.

[ZDan]

Originally Posted by Goingnowherefast

But again, it's not the oil breaking down that's the danger here. It's the worry that the viscosity of the oil drops low enough that it's unable to provide adequate lubrication to the bearings. I'd recommend sending your oil out to Blackstone for analysis if you plan on not running and oil cooler.

You pick oil viscosity based on operating temps. At 275F, I think 30-weight is fine, at least for limited track usage. If I was track-only, I might go 40-weight. Probably HTHS more relevant anyway, 5w30 Redline is 3.7 HTHS.

I haven't sent oil out for analysis because I've seen reports of others who have. After typical HPDE-type track usage, "high" oil temps, with no oil cooler, the reports I've seen show little to no degradation of the oil, and normal amounts of wear metals.

[ZDan]

Originally Posted by FR-S2GT86

Just out of curiosity, did you verify with your tuner what the stock temperature limit is, whether it be 300 degrees like you've read somewhere, or some other value, and that he specifically lowered this limit in his tune?

No, and frankly I don't see any need to bother him about it. I know that my custom tune specifically commanded reduced throttle once ~275F was reached above some rpm limit. I wanted that feature removed, he instead bumped it to 285F, which is fine as I know it never continues upward from ~270-275F anyway and yeah, if it *does* start to go higher in retrospect I'd like the cutoff about there.

If he indeed lowered the limit, then I agree with you that you should be fine in the short term. However, if you're regularly tracking your car, I agree with @Kelse92 in that for the overall life of your engine, you should still install an oil cooler. If I were in your shoes and in the same situation, I would.

I think that the risks of running 3.7 HTHS 5w30 synthetic at 275F for 15-20 minute track sessions are minimal. The risks of having an aftermarket cooler are non-zero and in fact we have seen *plenty* of reports of leaks (oil dropped on track = bad, also fire hazard!) and even engine failures. My oil temp reliably goes up to just over 270F indicated and it *stays* there. Data logging confirms this. Spending time, $$$$, effort while introducing multiple new possible points of failure for me, for my usage, makes zero sense.

[FR-S2GT86]

Originally Posted by ZDan

No, and frankly I don't see any need to bother him about it. I know that my custom tune specifically commanded reduced throttle once ~275F was reached above some rpm limit. I wanted that feature removed, he instead bumped it to 285F, which is fine as I know it never continues upward from ~270-275F anyway and yeah, if it *does* start to go higher in retrospect I'd like the cutoff about there.



I think that the risks of running 3.7 HTHS 5w30 synthetic at 275F for 15-20 minute track sessions are minimal. The risks of having an aftermarket cooler are non-zero and in fact we have seen *plenty* of reports of leaks (oil dropped on track = bad, also fire hazard!) and even engine failures. My oil temp reliably goes up to just over 270F indicated and it *stays* there. Data logging confirms this. Spending time, $$$$, effort while introducing multiple new possible points of failure for me, for my usage, makes zero sense.

Understood, good luck. And congratulations, I hope you keep kicking ass at the track.

If I were to start tracking my car after supercharging, I think I would try to introduce some additional cooling in the form of a distilled water mist directly into the intercooler/radiator/air conditioning condenser stack during mid to high RPMs. It wouldn't be too difficult to set up. I did notice that when I was installing my intercooler that the upper 1/3 of the radiator was very clean compared to the lower 2/3, as if air wasn't passing through it. Probably due to the design of the grille and the crash bar behind it. This might be a safer and inexpensive alternative that you could consider for those hot track days.

[Dzmitry]

Originally Posted by Goingnowherefast

But again, it's not the oil breaking down that's the danger here. It's the worry that the viscosity of the oil drops low enough that it's unable to provide adequate lubrication to the bearings. I'd recommend sending your oil out to Blackstone for analysis if you plan on not running and oil cooler.

https://www.ft86club.com/forums/showthread.php?t=146810

[ZDan]

Originally Posted by FR-S2GT86

Understood, good luck. And congratulations, I hope you keep kicking ass at the track.

Thanks! 2 points up going into last event which is at more of a Miata track, New Hampshire Motor Speedway (South Oval config).

If I were to start tracking my car after supercharging, I think I would try to introduce some additional cooling in the form of a distilled water mist directly into the intercooler/radiator/air conditioning condenser stack during mid to high RPMs. It wouldn't be too difficult to set up.

My approach would be to see how it goes with the stock cooling. If oil and coolant temps remain in check, I wouldn't bother...

I did notice that when I was installing my intercooler that the upper 1/3 of the radiator was very clean compared to the lower 2/3, as if air wasn't passing through it. Probably due to the design of the grille and the crash bar behind it. This might be a safer and inexpensive alternative that you could consider for those hot track days.

As I think about it, my *first* mod would be to vent the hood, which should improve cooling while reducing front lift. Hell maybe I should do that anyway, it's a zero-point mod with my club!

[gcranston]

Dan, I'm getting close to hood vents as well. Let's chat at NHMS.

[Goingnowherefast]

Originally Posted by Dzmitry

https://www.ft86club.com/forums/showthread.php?t=146810

That's not his car though lol. Every engine is different and the use case and climate is vastly different. I'm just saying it's pretty cheap insurance - like an oil cooler.

[ZDan]

Originally Posted by gcranston

Dan, I'm getting close to hood vents as well. Let's chat at NHMS.

Do you have a sawzall?

[Dzmitry]

Originally Posted by Goingnowherefast

That's not his car though lol. Every engine is different and the use case and climate is vastly different. I'm just saying it's pretty cheap insurance - like an oil cooler.

Oh yes agreed. I thought you were just looking for general UOA info from this platform under high temps.

[ZDan]

Originally Posted by Goingnowherefast

That's not his car though lol. Every engine is different and the use case and climate is vastly different. I'm just saying it's pretty cheap insurance - like an oil cooler.

Oil analysis would tell me what's going on in my engine, which would be good info. I might do it but honestly I'm not that worried.

Adding an oil cooler when it isn't necessary is not "cheap insurance". You're adding some risks, but you're not ensuring you won't have issues. Engines (particularly '13s) have had oiling-related failures while running an oil cooler. The oiling-related problems FA20 engines have had seem to me to be more related to oil delivery rather than oil temperature.