[tecmec]

I've been tracking my 2016 SS for years, but I've never paid much attention to oil pressure. I was looking at some of my AIM logs today though and I notice that it's generally pretty low during track use. It generally warms up to 270F (which seems about average around here?) and the pressure hangs around 40psi. I'm running Mobil 1 Supercar 0w-40.

Is this normal? 40psi sounds low. I do see short-ish periods of up to about 70psi on an out-lap on the top-end of revs when the oil is around 190F. But anything after the first lap, I don't see pressures ever above 50psi.

I guess on the bright side I don't see it dropping *below* 40psi, but I dunno.

What do others see?

[Msquared]

I think this is pretty normal. The oil pumps on our engines have active volume management (and therefore pressure management) by the ECM, so the pressure/output isn't really tied to engine speed like in older engines. I don't know what all parameters it uses to vary the volume, but I imagine one is that it limits time spent at high pressure to keep it from collecting too much oil in the top of the engine.

BTW, if you're doing a lot of track driving, I would suggest going with M1 0w-40 X4 instead of Supercar. It is still Dexos R rated, but it has better high-temp/high-shear and better resistance to viscosity breakdown than Supercar.

[N Camarolina]

Originally Posted by Msquared

BTW, if you're doing a lot of track driving, I would suggest going with M1 0w-40 X4 instead of Supercar. It is still Dexos R rated, but it has better high-temp/high-shear and better resistance to viscosity breakdown than Supercar.

Amen brother! I bought 3 changes worth of Supercar when the X3 was no longer available and Supercar was the only thing Dexos 2 (or R) rated at the time. But now that X4 is on the list, I've bought some of that instead.

Now I just need to figure out how to use up the Supercar, preferably not on track!

[VaporPressure]

This is my data for sessions at 2 different tracks in a '18 ZLE with an updated (but still OEM) oil pump. 15W-50 oil. Oil temps are 265-275.



Oil pressure is plotted against RPM, excluding in and out laps. I'm mostly 35-55 psi with a trend toward higher pressures at higher RPMs. Plenty of pressures up into the 60s and 70s though. Not sure if the difference in SS vs ZL1 explains that or not.

[Eric10905]

I don’t have the detailed data you have but I watch oil pressure during the track sessions. I run around 40 as well throughout the sessions. I used to use the 0w-40 as well but changed a while back to 15w-50. No change in pressure from that I noticed. Might switch to the 5w-50 next since it gets occasional street driving beside the track duty.

[Msquared]

Originally Posted by VaporPressure

This is my data for sessions at 2 different tracks in a '18 ZLE with an updated (but still OEM) oil pump. 15W-50 oil. Oil temps are 265-275.



Oil pressure is plotted against RPM, excluding in and out laps. I'm mostly 35-55 psi with a trend toward higher pressures at higher RPMs. Plenty of pressures up into the 60s and 70s though. Not sure if the difference in SS vs ZL1 explains that or not.

I kind of doubt it's the difference between engines, but maybe Chevy does calibrate the ZLE to move more oil. But there's a pretty big difference between the hot (100C) viscosity of the 15w-50 oil you're using vs the Supercar 0w-40 the OP is using, especially if his isn't a fresh fill. Your oil has a viscosity of 18 mm2/s, whereas his Supercar 0w-40 is 12.9 on its best (brand new) day, and will shear down to considerably less than that after a couple lapping sessions.* That probably accounts for most/all of the difference.

*The 0w-40 X4 has a 100C viscosity of 13.9, a significantly better high-temp-high-shear viscosity (3.8 vs 3.53), and resists viscosity breakdown over time a good bit better than the Supercar. It still has nearly as good cold-start (40C) viscosity as the Supercar, so it's still a great daily-driver/do-it-all oil, but it's just a much better option on track than Supercar. The 15w-50 is great on track, but not great for a daily because it flows much slower at ambient temps, and it has more calcium and other stuff that isn't good for DI engines over the long run. FWIW, I'm splitting the difference with my no-longer-daily-driven SS 1LE by using Supercar 5w-50. It's a very intriguing oil!

[VaporPressure]

That makes sense. Maybe also explains why he doesn't see high pressures after the outlap, once the oil is hot.

[tecmec]

Thanks for all the replies.

My curve certainly has a similar shape, but is a little more shallow.

I was debating switching to 5W-50. I'll probably either do that next, or switch to the 0W-40 X4. It sounds like the general consensus is that it's probably not a problem though.

For what it's worth, this oil is pretty new. All it's seen is two track days.