Dan H.

Looking forward to getting my oil temp issues under control. I'm installing the DRM stand alone kit in my C5 Z06. I have the larger core option. I've been running 15w-50 to help with the heat based on a lot of different recommendations. With a cooler addressing the temps, should I be running an oil closer to stock or should I continue with the 15-50, or somewhere in between? Pretty excited to focus on driving and not temps!

ZedO6

I run the same cooler in a C5Z and use 10-40W M1 without issue. You could and probably should drop to a lower viscosity if the cooler is keeping the oil temps below 270. (let the debate begin...)

A couple of things to note...you will find if your car sits a lot between events like mine does, it will take quite a bit longer to build oil pressure when cold after sitting. I now pull the fuel pump fuse and spin the engine over (10 secs on/15 secs off) to build oil pressure before I fire it. Probably overkill but I didn't like 20 secs of no oil pressure.

CHJ In Virginia

I used the DRM separate oil cooler on my C5/Z06. It was the smaller of the two offered. Placement of the cooler is very important. Do it like DRM recommends for best results. I used M1 5/30W oil without problems for 8 years and over 20K track miles. Never saw over 260 oil temps even at VIR with 105 deg ambient temps one August.

brkntrxn

No, stick with what you have.

Last C5

I run 0-40 with my DRM cooler.

Ludeaem

I would think it depends on several factors so pick your poison so to speak.Mobil 0-40 (which is what i use) is readily available and even on 90 degree 30 minute sessions I never saw temps go over 266. Granted that was with a Ron Davis radiator with EOC.

Your 15-50 probably has a lot more Zinc content but as you have mentioned before you have to wait awhile before oil temps get to a reasonable level from cold. I would do a few Blackstone analysis tests after a few events and go from there. Might find your answer or peace of mind that way. Good luck!

Dan H.

Thanks for the posts guys. Seems like folks run just about any oil in this motor without noticeable issues. I tend to want to change several variables all at once. I feel like what I am hearing here is "it depends". Unlike the 15-50 in a totally stock setup, there is less of a consensus once your equipment is better able to handle track duty.

In an effort to isolate variables, I think I'll continue using 15-50. Difference is I'll start doing the Blackstone analysis to see what it says. Once I have that, I can try 10-40 and see what that report says. And start making decisions based on that.

I'd like to run something lighter so that I don't have to let it warm up for 15 minutes to drive to a cruise night or to work. On track protection is still the most important, if I can make it easier to bomb around town at home well that would be good too.

brkntrxn

If you are worried about around town warmup temps, fabricate a simple cover to zip tie over the oil cooler between track days.

Dan H.

I talked to Randy at DRM a bit last week. He recommended covering it with tin foil in late fall and early spring. I like the small cover idea also, feels a bit more secure.