Is need of external oil cooler overblown

[autoracer86]

Originally Posted by blsfrs

It seems some of the JR Dual rads have more pressure drop than others.

Just curious, have you done an oil analysis?

Do you happen to know if there is any info on the JR race when it comes to pressure drop ?

[ZDan]

FWIW I ran 50 track days with my '17 BRZ PP, hitting upwards of 275F indicated at every single one of them. Usually ran 5w30 but also 0w20 for a few events. Never any issues. Friend's '17 with similar street/track miles as mine had his fail at Palmer MA last year, and he ran an oil cooler.

I think the indicated temperature is a calculated/adjusted value, not straight reporting from the sensor. I can't find it now but somewhere in these forums someone reported that 275F indicated corresponds to 255F measured sump temp. That's down to where you'd be ok with non-synthetic even (not that I would recommend it). Synthetics are good for sump temps up to at least 300F.

Obsession with lower oil temperatures in these cars is IMO misguided. It would be one thing if high track oil temps correlated with failure rate, but as near as I can tell as many failed tracked engines have had oil coolers as not. I researched that obsessively for months before I bought my first BRZ in Dec. 2017 and then again after I started tracking it. No correlation between failures and cooler vs. no-cooler.

[autoracer86]

Any information on why your friends motor failed ?

[ZDan]

Originally Posted by autoracer86

Any information on why your friends motor failed ?

He found a decent amount of RTV partially blocking the pickup tube...

[autoracer86]

Originally Posted by ZDan

He found a decent amount of RTV partially blocking the pickup tube...

Oh okay. I wonder if logging oil pressure could help catch something like that before it’s too late. Thanks for the info

[blsfrs]

Originally Posted by autoracer86

Do you happen to know if there is any info on the JR race when it comes to pressure drop ?

These guys had a significant drop in their GR86. Later in the thread a guy had a drop that was blamed on reusing the dual rad after a rocker arm ejection.

https://www.ft86club.com/forums/showthread.php?t=153935

I had a huge drop as well.

https://www.ft86club.com/forums/showthread.php?t=153186

[autoracer86]

Thanks for the links. I will be logging oil pressure for my next track day. Hopefully I don’t need to remove the oil cooler I won’t be buying the jr dual that’s for sure…

I have a first gen fyi so not sure how much of the info is the links apply. Either way it was a good read

[blsfrs]

Originally Posted by autoracer86

Thanks for the links. I will be logging oil pressure for my next track day. Hopefully I don’t need to remove the oil cooler I won’t be buying the jr dual that’s for sure…

I have a first gen fyi so not sure how much of the info is the links apply. Either way it was a good read

My car is 1st gen. One of the posters (with the JR dual rad) in the first thread is also 1st gen.

IMHO: The oiling systems in the 2 engines are similar enough where the pressure drop due to cooler restrictions should be comparable.

As I understand it, the issue with the Gen 2 is with right turns due to pan and pickup configuration.

If you are comfortable with @ZDan's research, a cooler is a waste of time and money.

[ZDan]

Originally Posted by blsfrs

As I understand it, the issue with the Gen 2 is with right turns due to pan and pickup configuration.

Yup. I am 0% worried about running Redline 5w30 (or even Subaru 0w20 really) at 275F indicated oil temp. But I am strongly considering an Accusump for the '23, as pressure drop in right handers is a known real thing, and failures are happening. Ansix Auto has a great vid documenting pressure drops before and after Accusump, goes from being frankly quite worrying, to meh, prolly no big deal...

[autoracer86]

I’m more worried about pressure than temps. I will just see what the data shows after my next track day and go for there.

[new2subaru]

Originally Posted by blsfrs

It seems some of the JR Dual rads have more pressure drop than others.

Just curious, have you done an oil analysis?

I thought that was debunked and was a Honda thing. We're talking Gen 1? As far a I recall there wasn't an issue with pressure dropping.

It's cheaper and more beneficial to just drop the oil. I drop it every 2-3 track days. It's about $35 CDN without filter. It's not worth getting an analysis done. Yes, it could be overkill but it's cheap insurance.

[blsfrs]

Originally Posted by ZDan

Yup. I am 0% worried about running Redline 5w30 (or even Subaru 0w20 really) at 275F indicated oil temp. But I am strongly considering an Accusump for the '23, as pressure drop in right handers is a known real thing, and failures are happening. Ansix Auto has a great vid documenting pressure drops before and after Accusump, goes from being frankly quite worrying, to meh, prolly no big deal...

In your current and 2017 twin, what radiators are you using?

[ZDan]

Stock, coolant temps never get much above 200F

Originally Posted by blsfrs

In your current and 2017 twin, what radiators are you using?

[blsfrs]

Originally Posted by ZDan

Stock, coolant temps never get much above 200F

Why do you have to break all of the rules?

Everybody "knows" you have to have a racing radiator and an oil cooler. The internet says so, so it must be true.