Oil Pressure Drop

[OldBiker]

Latest from 900BRZ:

Yeah!! So the best solution: large capacity oil plan + integrated baffle. Excellent video to go along with it, explaining the experiment and logic. Can't wait to see the final product!

[ZDan]

Yeah, that looks like the ultimate answer. Meanwhile before pan is available, Accusump looks like the best solution at the moment.

Tryna decide whether to go ahead and get Accusump and then the deeper aftermarket oil pan solution when it is available, or get an ND2...

[Frost]

Originally Posted by ZDan

Yeah, that looks like the ultimate answer. Meanwhile before pan is available, Accusump looks like the best solution at the moment.

Tryna decide whether to go ahead and get Accusump and then the deeper aftermarket oil pan solution when it is available, or get an ND2...

ND2 is tremendous amounts of fun but that suspension is way to soft for anyone who wants to be competitive. I personally would get one for a sunday driver but not necessarily a time attack or track rat.

[ZDan]

Originally Posted by Frost

ND2 is tremendous amounts of fun but that suspension is way to soft for anyone who wants to be competitive. I personally would get one for a sunday driver but not necessarily a time attack or track rat.

Yeah no way it would stay on stock suspension, would be getting coilovers, roll bar, and a lower and more supportive drivers seat right away. We are spoiled with BRZ seats!

[Dirty Harry]

Originally Posted by ZDan

Yeah, that looks like the ultimate answer. Meanwhile before pan is available, Accusump looks like the best solution at the moment.

Tryna decide whether to go ahead and get Accusump and then the deeper aftermarket oil pan solution when it is available, or get an ND2...

So you think the issue is that serious that you’d swap cars? Pretty big call. I don’t know heaps about the issue, but it sounds like it’s the main flaw with the new one. So the first gen didn’t have these types of issues at all?

[whataboutbob]

Originally Posted by Dirty Harry

So you think the issue is that serious that’d you’d swap cars? Pretty big call. I don’t know heaps about the issue, but it sounds like it’s the main flaw with the new one. So the first gen didn’t have these types of issues at all?

I'm pretty sure the 1st gen had issues. Especially if; 1) You let the oil get low and then drove it hard, 2) Added FI, and/or: 2.a) Let the oil get low, 2.b) Drove it hard, 2.c) Didn't address the oil cooling issues, 2.d) Had a shitty motor build (OEM or aftermarket), or 2.e) All of the above

[autoracer86]

Originally Posted by Dirty Harry

So you think the issue is that serious that you’d swap cars? Pretty big call. I don’t know heaps about the issue, but it sounds like it’s the main flaw with the new one. So the first gen didn’t have these types of issues at all?

Oil pressure wasn't great if oil temps were too high on the first gen. Lots of info on this online

On the second gen oil pressure will drop on track based on load from right hand turns regardless of the temperature.

Street driving seems to be fine so if you don't track your car its not much of an issue

[ZDan]

Originally Posted by Dirty Harry

So you think the issue is that serious that you’d swap cars? Pretty big call. I don’t know heaps about the issue, but it sounds like it’s the main flaw with the new one. So the first gen didn’t have these types of issues at all?

1st-gen isn't perfect in this regard, but the 2nd-gen definitely has an issue with pressure drops under track usage, particularly during right-handers on decently-suspended cars with higher-grip tires.

I tracked my 1st gen ~12 track days/year for five years, I wasn't monitoring oil pressure though.

Anyway I test-drove an ND2 last year and it was a hoot, reminded me a bit of my old 240Z being similar weight (slightly heavier) and with driver sitting right at the rear wheels. I got the '23 BRZ because more utility as it was going to be my only car. Since then I've picked up an '05 Mazda3 hatch as a daily so the ND2 is more of an option now. Also I've been having to run a ton of ballast for time trials, and for this year they've added 80 lb. more Victory ballast... So anyway my competition weight with the '23 BRZ would be 3187 lb. this year. Kinda nullifies one of the best things about the car... Even at 3107 lb. last year I could *feel* the mass. Could run ND2 at 2475 lb. which sounds like fun...

[ZDan]

Originally Posted by whataboutbob

I'm pretty sure the 1st gen had issues. Especially if; 1) You let the oil get low and then drove it hard, 2) Added FI, and/or: 2.a) Let the oil get low, 2.b) Drove it hard, 2.c) Didn't address the oil cooling issues, 2.d) Had a shitty motor build (OEM or aftermarket), or 2.e) All of the above

*What* oil cooling issues? My gen-1's oil temp always went to 270-275F *indicated*, every session for 5 years, ~50 track days, never went beyond that. 275F indicated oil temp has been correlated to 255F sump temp. These temps are no prob at all for any decent synthetic oil.

Originally Posted by autoracer86

Oil pressure wasn't great if oil temps were too high on the first gen. Lots of info on this online

Data shows that measured oil pressure with 5w30 is the same with an oil cooler at 250F, as with NO oil cooler at 275F. I.e., pressure drop from the oil cooler is equal to pressure drop due to higher temp with no oil cooler.
And anyway you can easily go to 40-weight if want higher pressure at temp with no oil cooler.

I did a pretty exhaustive search when I got my car in late 2017 and found that engine failures were not correlated at all with whether or not an oil cooler was present. In fact it seemed to me that *most* track failures were *with* an oil cooler. There were RTV issues and general oiling issues particularly for #3 not related at all to oil temperatures.

Again, 275F indicated/255F sump was never the problem...

[autoracer86]

Originally Posted by ZDan

*What* oil cooling issues? My gen-1's oil temp always went to 270-275F *indicated*, every session for 5 years, ~50 track days, never went beyond that. 275F indicated oil temp has been correlated to 255F sump temp. These temps are no prob at all for any decent synthetic oil.


Data shows that measured oil pressure with 5w30 is the same with an oil cooler at 250F, as with NO oil cooler at 275F. I.e., pressure drop from the oil cooler is equal to pressure drop due to higher temp with no oil cooler.
And anyway you can easily go to 40-weight if want higher pressure at temp with no oil cooler.

I did a pretty exhaustive search when I got my car in late 2017 and found that engine failures were not correlated at all with whether or not an oil cooler was present. In fact it seemed to me that *most* track failures were *with* an oil cooler. There were RTV issues and general oiling issues particularly for #3 not related at all to oil temperatures.

Again, 275F indicated/255F sump was never the problem...

Do you have this saved to a text file ? LOL

[ZDan]

Originally Posted by autoracer86

Do you have this saved to a text file ? LOL

I should...

[OkieSnuffBox]

Originally Posted by ZDan

Yeah no way it would stay on stock suspension, would be getting coilovers, roll bar, and a lower and more supportive drivers seat right away. We are spoiled with BRZ seats!

The seeming requirement of engine, transmission, diff coolers after 949's and FM's testing is kind of a bummer.

And FM has stronger case bolts for the transmission because the case itself twisting was found to be the reason cars tracked hard were having transmission failures.......I don't remember if they made the cases stronger for ND2s.

[ZDan]

Originally Posted by OkieSnuffBox

The seeming requirement of engine, transmission, diff coolers after 949's and FM's testing is kind of a bummer.

And FM has stronger case bolts for the transmission because the case itself twisting was found to be the reason cars tracked hard were having transmission failures.......I don't remember if they made the cases stronger for ND2s.

Thanks for the food for thought! I had thought the fragile gearbox had been fixed by ND2, looking into it... Ditto for trans and diff cooling. Just joined forum.miata.net and posted up Qs on the track forum.

[Petah78]

Interesting, i have heard that the ND2 has a glass trans which never got resolved this is up to 2023. The only solution was to swap in a NC 6sp. This is the first i have heard about the requirement for a diff/trans/engine cooler.......