QTB

I have a 350Z with an LS swap that I use as a Time Trials car. I've done a couple events this year and I'm wondering what sort of oil and water temps are normal for this engine under race conditions?

I'm keeping my sessions short to about 5 laps and then a cool down lap but it's still having water temps in the 245F range and the oil is 270-280F range. Which seems somewhat high on both sides.

Other Details:
I'm using distilled water and Redline water wetter in the coolant system. I have a fairly large oil cooler with an accusump (3qt). My entire oil system holds about 11 qts and is using a Katech blue printed pump. The lifters are also solid lifters with 3/8" holes in the lifter trays to improve drain back.

I'm going to work on getting the air dam better blocked off so I get most of the air actually going through the radiator and plan on getting a vented hood as well.

Thoughts/comments?

Joseph Freda

That's way too hot. I would not run an aluminum LS engine above 220 degrees. A couple of things to check on. Air flow ducting into rad, air flow out of the back of rad, water pump speed, thermostat, air bleeds on engine. If your turn the water pump too fast it can cavitate or flow water through the rad too fast. Have you tried running without the thermostat. They can be very restrictive. They can be replaced with plates with different sized holes in the middle. Do you run the air bleeds on the top of the heads. These should bleed off air to the rad or a header tank. A small amount of air trapped in the engine can make the cooling system work inefficiently.

BTW, our high HP LS2 engine ran the whole last NASA race at RA for 30 min at 180 water, 180 oil, so it can be done.

dbs1

I'd love to get my LS3 based 640hp 416 to run at 180 degrees but havn't been able to get there yet. After getting a Ron Davis huge by large dual elec fan radiator as well as the biggest Setrab oil cooler I could fit on my 02 camaro on days pushing 90 degrees I'll see 210 water temps and 280 oil temps. New air dam and all.

Make sure you have some race oil that can handle those kind of temps. After much research I'm running Mobile 1 RACE OIL 0-30w.

ls1 1990 VN

I wouldn't run that oil in my 91 Camry DD

Joseph Freda

Make sure the shroud has been removed from the back of the rad to improve air flow out of the rad at race speed. Hood and fender vents will also help move the air out from under the hood. Most folks concentrate on getting the air into the rad with shrouding, but where that air goes after it comes out the back side is equally as important. I also prefer a oil heat exchanger inside the rad. It helps get the oil temp to operating temps faster and a liquid-liquid heater exchanger (cooler) is more efficient than an air-liquid heat exchanger.