Oil Cooler Question
 

Ok guys, another noob question for you. So, I ran Buttonwillow yesterday CCW13 and it was almost 100 degrees. The Z ran flawlessly going flat out for three twenty-minute sessions. I kept the car mainly in third gear; utilizing the complete bandwidth of the engine, so I hang-out close to red-line quite often. My question revolves around oil coolers, what signs outside of an overheating engine indicate the need for an oil cooler? Again, I had no over heating issues, just being cautious as I may be missing something.

Here are some quick facts about the car to better answer my question:
05 Base w/VLSD
98k on the engine
Engine-stock, running basic bolt-on’s and Z1 oil pan spacer. Stock cooling.
Suspension-stock
Wheels & Tires; 275/18 on 10.5 Federal RS-RR square.
Brakes-07 twin piston caliper; Motul 600, Carbotech X10 &X8
All fluids replaced annually.
Weekend/track car. I put only about 2K.

Thanks in advance,

Neil

I am by no means an expert on tracking these cars, but I do know that while a hot track day on the stock cooling system won't necessarily cause any issues (engine water temp will not reach dangerous levels), the engine oil temp is not monitored or displayed, and that is what will cause problems. As the oil heats up beyond intended operating temps it can become less viscous, which will lessen the oil's ability to properly lubricate crank bearing journals and other critical engine components. Since you have an oil pan spacer your oil capacity is larger, thus it will take your oil longer to reach those critical temps, but from what I've read an oil cooler is more-or-less required for sustained track work, especially in 100°F weather.

It's probably worth doing an oil change soon, and sending a sample of that oil in for analysis (from BlackStone labs or similar). The oil analysis will be able to tell you if there was excessive engine wear due to overheated oil (BlackStone has a 'baseline' for these engines based on other reports they have done), or if the oil has broken down more than expected indicating it was overheated (changes in viscosity or flash point).

Thanks for your insight, I hadn’t thought about an oil analysis so agreed that should be the next step.

I usually don't run in September, opting to take the summers off; June-Sept. and returning back in mid October. Number one mod to prevent overheating…don't run in 100-degree weather!!!! Track days in SoCal are no fun when you have to hide from the sun under an awning or EZ-Up without a cool adult beverage in hand. Thanks again.

Oh and those calipers look amazing!!

Neil

Well the most obvious sign is coolant temperature rising above the middle, but that doesn't mean that if the coolant temps stays in the middle the oil temperature is ideal. The extra quart of oil certainly helps the engine stay there but, ultimately, at least on these engines, the oil cooler is a must to keep things under 250 degrees oil temp depending on other factors. An oil temperature gauge is recommended. You want to monitor.

I would tell you to add a simple oil cooler. Oil has an optimal temperature (and I believe it's around 210 degrees and maybe it's different for different oil types/grades). One piece of advice that has stuck with me is that coolant cools your engine block and oil cools your engine internals. If you look at newer / more track focused vehicles (especially the track-intended corvette and Camaros) they are adding multiple coolers - the C7 is up to 13 coolers now??

Something as basic as a 12" x 8" cooler coming off a filter sandwich plate would be my recommendation

Thanks all for your insight. So in a nut shell; go get an oil-cooler before things go south! Message understood. My wallet was getting too heavy anyway....
Thanks again.

Neil

I run two oil coolers … one for the engine and one pre-turbo. I bought my two Setrabs used for ~$80/each, a sandwich plate for $40 and $40 for hoses. Doesn't have to be expensive.

Here is my DIY writeup :)
https://my350z.com/forum/engine-driv...s-hp-cars.html