follow ft86club on our blog, twitter or facebook.
FT86CLUB
Ft86Club
Speed By Design
Register Garage Members List Calendar Search Today's Posts Mark Forums Read

Go Back   Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB > Technical Topics > Engine, Exhaust, Transmission

Engine, Exhaust, Transmission Discuss the FR-S | 86 | BRZ engine, exhaust and drivetrain.


User Tag List

Reply
 
Thread Tools Search this Thread
Old 11-15-2023, 08:23 PM   #57
Tatsu333
Senior Member
 
Join Date: Jan 2017
Drives: 2020 BRZ Sport Tech RS
Location: Canada
Posts: 372
Thanks: 452
Thanked 263 Times in 148 Posts
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by ZDan View Post
Do not know what my oil pressure is, no gauge. I'd probably worry if/when it dropped below maybe 32psi. For temp, in my '17 it always went to about 275F indicated (reportedly this corresponds to about 255F sump temp). In the new car it reads slightly below that, maybe 270F? I was never particularly worried at 275 indicated running 30wt synthetic. I guess if I had to call a cutoff temp, maybe 300F?

Which is I run 30wt for track duty. Track-only I'd probably run 40wt, but street/track in warmer months I just run 5w30.

Yeah, about that. That said, research of others suggests that my oil pressure has been dropping well below that during right-handers at the track in the new car... Might get an Accusump for next year.
I saw a post somewhere that someone "solved" their pressure drop issue by over-filling their oil by 1 quart for track use. Presumably they drained off the over-fill for the street.

I'm curious as to your thoughts on that idea? (and anyone else who'd like to chime in, feel free)
__________________
Tatsu333 is offline   Reply With Quote
The Following User Says Thank You to Tatsu333 For This Useful Post:
blsfrs (11-15-2023)
Old 11-15-2023, 10:40 PM   #58
blsfrs
Senior Member
 
blsfrs's Avatar
 
Join Date: Dec 2018
Drives: 2013 frs base
Location: central Virginia
Posts: 1,282
Thanks: 2,153
Thanked 1,228 Times in 587 Posts
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by ZDan View Post
Do not know what my oil pressure is, no gauge. I'd probably worry if/when it dropped below maybe 32psi. For temp, in my '17 it always went to about 275F indicated (reportedly this corresponds to about 255F sump temp). In the new car it reads slightly below that, maybe 270F? I was never particularly worried at 275 indicated running 30wt synthetic. I guess if I had to call a cutoff temp, maybe 300F?

Which is I run 30wt for track duty. Track-only I'd probably run 40wt, but street/track in warmer months I just run 5w30.

Yeah, about that. That said, research of others suggests that my oil pressure has been dropping well below that during right-handers at the track in the new car... Might get an Accusump for next year.
Last month at VIR, I was running Mobil 10w30, I was seeing oil psi in the mid 50's in the 230*-240* range. Closer to 250*, pressure was dropping to the 40's.

So, I'm seeing a rough trend of a 10psi drop per 10* temperature increase. If the trend continues, at 260* the psi is in the 30's. At 270* the redline pressure could be in the 20's, etc. Combine that with loss of pressure in right hand turns and you could have a problem.

I would like to not need a cooler but my gut is saying something different. I'm open to any solid data that says my gut is wrong.
blsfrs is offline   Reply With Quote
Old 11-16-2023, 08:13 AM   #59
ZDan
Senior Member
 
ZDan's Avatar
 
Join Date: May 2011
Drives: '23 BRZ
Location: Providence, RI
Posts: 4,634
Thanks: 1,417
Thanked 3,963 Times in 2,071 Posts
Mentioned: 85 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by Tatsu333 View Post
I saw a post somewhere that someone "solved" their pressure drop issue by over-filling their oil by 1 quart for track use. Presumably they drained off the over-fill for the street.

I'm curious as to your thoughts on that idea? (and anyone else who'd like to chime in, feel free)
Saw that as well, but IMO inconclusive. FWIW I've been running +1/2-quart overfilled this season as a hedge, but... @BRZ900 added half a quart beyond full and it made little/no difference to the pressure drops they were getting during right-handers. Also, a couple of rounds of baffle designs didn't help either. Accusump appears to be the only proven solution.
ZDan is offline   Reply With Quote
The Following 3 Users Say Thank You to ZDan For This Useful Post:
blsfrs (11-16-2023), Tatsu333 (11-16-2023), x808drifter (11-16-2023)
Old 11-16-2023, 08:46 AM   #60
ZDan
Senior Member
 
ZDan's Avatar
 
Join Date: May 2011
Drives: '23 BRZ
Location: Providence, RI
Posts: 4,634
Thanks: 1,417
Thanked 3,963 Times in 2,071 Posts
Mentioned: 85 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by blsfrs View Post
Last month at VIR, I was running Mobil 10w30, I was seeing oil psi in the mid 50's in the 230*-240* range. Closer to 250*, pressure was dropping to the 40's.
Assuming 55psi at 235F, and 48psi at 248F. 12.7% drop in pressure with +13F indicated oil temp, call it 10% per 10F.

Quote:
So, I'm seeing a rough trend of a 10psi drop per 10* temperature increase. If the trend continues, at 260* the psi is in the 30's. At 270* the redline pressure could be in the 20's, etc. Combine that with loss of pressure in right hand turns and you could have a problem.
Pressure will not drop off linearly with temperature. It'll be more like 10%/10F. At that rate, I calculate ~40psi at 275F (55psi @ 235F * 0.9^3 = 40psi). This isn't going to be exactly right either, but a lot closer than assuming linear decrease in pressure.

Quote:
I would like to not need a cooler but my gut is saying something different. I'm open to any solid data that says my gut is wrong.
I researched this pretty heavily when I bought my '17. Looking at failures I was kind of amazed at how many engine failures were cars with oil coolers. Near as I could tell there was *zero* correlation between failures and whether the car had an oil cooler or not.

This info, combined with tracking the car and seeing oil temp always stabilize just below 275F and never continuing to rise, and knowledge that good synthetic oils are good for over 300F *sump* temps, I decided I didn't need one.

Anyway here's some data (link to thread: https://www.ft86club.com/forums/showthread.php?t=91820 ) to show how much pressure you get going from 20wt to 30wt with no cooler at ~275F (blue and yellow) , and then what happens with a cooler at 250F (green). Note that pressure is about *the same* with 30wt oil either without the cooler at 275F, or *with* oil cooler at 250F. I.e. the pressure drop due to this cooler totally offsets whatever pressure gain there should have been due to the oil running thicker at lower temp.

Answering the thread title, yes, "need" for an oil cooler for these cars is massively overstated/overblown. I'd go beyond that even and say that they more often cause problems than solve any. My 0.02!
Attached Images
 

Last edited by ZDan; 11-16-2023 at 09:00 AM.
ZDan is offline   Reply With Quote
The Following 3 Users Say Thank You to ZDan For This Useful Post:
blsfrs (11-16-2023), Tatsu333 (11-16-2023), Teseo (11-17-2023)
Old 11-16-2023, 11:09 AM   #61
autoracer86
Senior Member
 
autoracer86's Avatar
 
Join Date: Jul 2022
Drives: Toyota GT86
Location: Ireland
Posts: 576
Thanks: 511
Thanked 391 Times in 249 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by blsfrs View Post
Last month at VIR, I was running Mobil 10w30, I was seeing oil psi in the mid 50's in the 230*-240* range. Closer to 250*, pressure was dropping to the 40's.

So, I'm seeing a rough trend of a 10psi drop per 10* temperature increase. If the trend continues, at 260* the psi is in the 30's. At 270* the redline pressure could be in the 20's, etc. Combine that with loss of pressure in right hand turns and you could have a problem.

I would like to not need a cooler but my gut is saying something different. I'm open to any solid data that says my gut is wrong.
I am with you on this @blsfrs. Running a cooler and keeping the oil pressure high just makes sense. Only a few people on this forum say not to run a cooler....

The best you can do is get your own data and do what gives you piece of mind. Which from what I can tell you're already doing.

What works for some people doesn't work for others. Like you I got myself an oil pressure setup and so far at cooler temps it seems fine. If I see pressure under say 45/40 at higher temps I am going to get a proper cooler(running a oem setup at the moment)

Anyway do you
autoracer86 is offline   Reply With Quote
The Following User Says Thank You to autoracer86 For This Useful Post:
blsfrs (11-16-2023)
Old 11-16-2023, 10:02 PM   #62
ZDan
Senior Member
 
ZDan's Avatar
 
Join Date: May 2011
Drives: '23 BRZ
Location: Providence, RI
Posts: 4,634
Thanks: 1,417
Thanked 3,963 Times in 2,071 Posts
Mentioned: 85 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by autoracer86 View Post
I am with you on this @blsfrs. Running a cooler and keeping the oil pressure high just makes sense. Only a few people on this forum say not to run a cooler....
It is no prob to simply run higher-viscosity oil if you're worried about oil pressure drop due to temp.

That said, we do have evidence (see above post) that an oil cooler itself can have enough pressure drop that there is zero benefit as far as "higher pressure". Hotter 5w30 oil at 275F without an oil cooler is at about the same pressure as 5w30 oil at 250F with an oil cooler.

My advice: don't bother with an oil cooler, these cars at stock power output just don't need them, and they add failure points. Engines *have been lost* due to leaky plumbing of aftermarket oil coolers! Also you are adding a fire risk. It's just not worth it when oil temps are *well* within reasonable range for good synthetic.
ZDan is offline   Reply With Quote
The Following 5 Users Say Thank You to ZDan For This Useful Post:
blsfrs (11-17-2023), Tatsu333 (11-17-2023), Teseo (11-17-2023), Tokay444 (11-17-2023), x808drifter (11-17-2023)
Old 11-19-2023, 12:36 PM   #63
blsfrs
Senior Member
 
blsfrs's Avatar
 
Join Date: Dec 2018
Drives: 2013 frs base
Location: central Virginia
Posts: 1,282
Thanks: 2,153
Thanked 1,228 Times in 587 Posts
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by ZDan View Post
It is no prob to simply run higher-viscosity oil if you're worried about oil pressure drop due to temp.

That said, we do have evidence (see above post) that an oil cooler itself can have enough pressure drop that there is zero benefit as far as "higher pressure". Hotter 5w30 oil at 275F without an oil cooler is at about the same pressure as 5w30 oil at 250F with an oil cooler.

My advice: don't bother with an oil cooler, these cars at stock power output just don't need them, and they add failure points. Engines *have been lost* due to leaky plumbing of aftermarket oil coolers! Also you are adding a fire risk. It's just not worth it when oil temps are *well* within reasonable range for good synthetic.
Thank you for the links.

I guess it gets down to one's comfort level.

At redline, am I comfortable at 270* and oil psi in the 30's? Or, do I want to risk the down sides of a cooler and maintain 230* and 50 psi?
blsfrs is offline   Reply With Quote
The Following User Says Thank You to blsfrs For This Useful Post:
autoracer86 (11-19-2023)
Old 11-19-2023, 03:22 PM   #64
Tokay444
Anti stance.
 
Tokay444's Avatar
 
Join Date: Feb 2016
Drives: 17 White 860. RCE Tarmac 2. RE-71RS
Location: Not Canada
Posts: 1,692
Thanks: 915
Thanked 990 Times in 566 Posts
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Or do you want to run appropriate weight oil for the type of driving you’re doing?
Tokay444 is offline   Reply With Quote
The Following User Says Thank You to Tokay444 For This Useful Post:
ZDan (11-20-2023)
Old 11-20-2023, 01:59 PM   #65
terboboost
Member
 
terboboost's Avatar
 
Join Date: Feb 2022
Drives: 2013 BRZ HKS Turbo
Location: Chicago, IL
Posts: 61
Thanks: 1
Thanked 38 Times in 23 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by blsfrs View Post
It was a relatively cool day. My temperatures would be higher on a hot day with lower oil pressure.

So @ZDan and @terboboost, what does your pressure run at 260*? And what is your cut off point for pressure and temp? I've read where syn oil doesn't break down like dino oil does but it does thin out at high temperatures. What minimum pressure are you guys comfortable with at redline? 30-35 psi?
This is what I'm comfortable with for oil pressure:
Oil Temp: 176*F
Idle Pressure: 7.3psi or more
6000 rpm: 73psi or more

I assume that the Subaru engineers are aware that oil pressure drops as temps rise, and have spec'd the oil system appropriately.

We know a good synthetic oil can withstand higher then 300*F sump temperatures. Oil pressure is not what prevents metal on metal contact in bearings, oil shear performs that job.

Personally, I overfill .5-1 qt and maintain oil temps below about 270. However, the 270 limit is mostly because if oil temps are getting that hot, there are a million other parts on the car that are also getting very very hot, and I'm trying to protect the entire car, ESPECIALLY the components whose temperature I do not know.

I'd stop trying to fix a problem that doesn't exist.
__________________
IG: @terboboost | Twitter: @terboboost | youtube.com/@terboboost | D-corp.co
terboboost is offline   Reply With Quote
The Following 3 Users Say Thank You to terboboost For This Useful Post:
blsfrs (11-20-2023), x808drifter (11-20-2023), ZDan (11-21-2023)
Old 11-20-2023, 02:08 PM   #66
x808drifter
LMGTFY
 
x808drifter's Avatar
 
Join Date: Mar 2016
Drives: 13 FRS, 91 Miata
Location: Lava Town, HI
Posts: 2,776
Thanks: 5,561
Thanked 3,648 Times in 1,625 Posts
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by terboboost View Post

I'd stop trying to fix a problem that doesn't exist.
THIS
x808drifter is offline   Reply With Quote
The Following User Says Thank You to x808drifter For This Useful Post:
blsfrs (11-20-2023)
Old 11-20-2023, 03:26 PM   #67
blsfrs
Senior Member
 
blsfrs's Avatar
 
Join Date: Dec 2018
Drives: 2013 frs base
Location: central Virginia
Posts: 1,282
Thanks: 2,153
Thanked 1,228 Times in 587 Posts
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by terboboost View Post
This is what I'm comfortable with for oil pressure:
Oil Temp: 176*F
Idle Pressure: 7.3psi or more
6000 rpm: 73psi or more

I assume that the Subaru engineers are aware that oil pressure drops as temps rise, and have spec'd the oil system appropriately.

We know a good synthetic oil can withstand higher then 300*F sump temperatures. Oil pressure is not what prevents metal on metal contact in bearings, oil shear performs that job.

Personally, I overfill .5-1 qt and maintain oil temps below about 270. However, the 270 limit is mostly because if oil temps are getting that hot, there are a million other parts on the car that are also getting very very hot, and I'm trying to protect the entire car, ESPECIALLY the components whose temperature I do not know.

I'd stop trying to fix a problem that doesn't exist.
Can you clarify a couple of things?

Did you mean 276*? What oil are you running?

And, at that temperature you have 73 psi at 6k rpm? Where is your sensor reading and is it reading correctly?

From what you guys say, high temp and lower pressure will work, but is it optimal?

Last edited by blsfrs; 11-20-2023 at 04:21 PM.
blsfrs is offline   Reply With Quote
Old 11-20-2023, 04:23 PM   #68
terboboost
Member
 
terboboost's Avatar
 
Join Date: Feb 2022
Drives: 2013 BRZ HKS Turbo
Location: Chicago, IL
Posts: 61
Thanks: 1
Thanked 38 Times in 23 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by blsfrs View Post
Can you clarify a couple of things?

Did you mean 276*?

And, at that temperature you have 73 psi at 6k rpm? Where is you sensor reading and is it correctly?

From what you guys say, high temp and lower pressure will work, but is it optimal?

Those are the factory service manual specifications, so it is 176*F.

I don't know what "optimal" oil temperature and pressure is. I only know what the factory engineers designed for mixed with 20 years of motorsports experience of what "works". That's all I need to stay on track with a reliable machine.
__________________
IG: @terboboost | Twitter: @terboboost | youtube.com/@terboboost | D-corp.co
terboboost is offline   Reply With Quote
The Following 2 Users Say Thank You to terboboost For This Useful Post:
blsfrs (11-20-2023), ZDan (11-21-2023)
Old 11-20-2023, 04:55 PM   #69
EAGLE5
Dismember
 
EAGLE5's Avatar
 
Join Date: Mar 2013
Drives: 2013 Red Scion FR-S
Location: Castro Valley
Posts: 5,562
Thanks: 2,153
Thanked 4,002 Times in 2,157 Posts
Mentioned: 43 Post(s)
Tagged: 1 Thread(s)
Garage
1. I'm pretty sure that temperature is not so good for oil or the engine.
2. I'm pretty sure that I don't want to keep changing my oil for rare track events.
3. I'm pretty sure that we don't have a scientific data sample.
4. I'm pretty sure that on a 100+ degree day at the track, especially with e85, the car can use every bit of cooling it can get. Those on asphalt temps are going to be even higher. With an oil cooler, even on 5-30, I'm not worried because I can get the heat out.
EAGLE5 is offline   Reply With Quote
The Following 3 Users Say Thank You to EAGLE5 For This Useful Post:
blsfrs (11-21-2023), new2subaru (11-21-2023), Ultramaroon (11-20-2023)
Old 11-20-2023, 05:00 PM   #70
Tokay444
Anti stance.
 
Tokay444's Avatar
 
Join Date: Feb 2016
Drives: 17 White 860. RCE Tarmac 2. RE-71RS
Location: Not Canada
Posts: 1,692
Thanks: 915
Thanked 990 Times in 566 Posts
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Does the JDM car have a different oiling system than the USDM model?
Tokay444 is offline   Reply With Quote
 
Reply

Tags
haha

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Full Race external oil cooler kit duqx Engine, Exhaust, Bolt-Ons 1 01-20-2019 09:41 PM
External mic placement Shark_Bait88 Tracking / Autocross / HPDE / Drifting 22 06-13-2016 07:39 PM
Anyone have info on the BRZ OEM external oil cooler (Japan only)? mav1178 Engine, Exhaust, Transmission 5 04-22-2016 01:20 AM
External Wastegate Question TurboBRZ Forced Induction 23 07-22-2015 01:38 PM


All times are GMT -4. The time now is 05:21 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
User Alert System provided by Advanced User Tagging v3.3.0 (Lite) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.

Garage vBulletin Plugins by Drive Thru Online, Inc.