Best oil operating temperature
 

Anybody know whats a decent operating temperature for oil? I'm looking to get an engine oil cooler and hook up my pillar gauge to it. I know the 3.8's get quite warm, and a little too warm on a hot enough day, so one of my main focuses is to get that engine to cool down a little.

Oil temp is "ballpark" around 220-240 with dino, 210-230 with synth. This helps eliminate moister ect, and oil temp normally runs a few degrees above the engine coolant temp. For an LT1 with a 190 Thermostat will have an oil temp around 210-230. With a 165 Thermo = oil temp in the 190-200 range. This is during normal driving. Hard use higher RPMs will raise the temp, you don't want to go over 300 degrees or the oil thins out allot and you will loose pressure.

My 350 CI with stock pan and factory oil cooler ran about 210 Castro semi-syth 10-30. In my 385 with the lower temp thermo, canton pan and no oil cooler I run about 195. Castrol semi-syth 10-40.

Also, you want the sensor in the oil pan, not in the block so you don't get false readings.

Nice trick I've seen is to drill and tap the sensor right into the drain plug if the pan don't have a fitting.

I'll have to tap my spare oil pan I got laying around, but in the mean time, that drain plug trick sounds pretty neat. Not sure when I'll get around to doing the project, but It's been on the to do list since I ran at e-towns road course in 95* heat a few years back. the trans fluid got cooked, and that has an external cooler on it.

Road racers can se oil temps nearing 300. You want to look at a oil cooler as well. The GM oil cooler that was stock on the early 4th gens were good for lowering oil temp 10-15 degrees. You can probably do a retro fit, not sure if the radiator were different as far as plumbing the coolant lines.

The pancake oil cooler that came on some 93-95 LT1s was an absolute piece of ****. So much that GM dropped it altogether as an option after the 1995 model year. There have been several instances of them clogging, some temperature studies that have proven that they don't even help, and are overall a very poor design.

Before I'd run with the KC4 idea I'd run an aftermarket cooler, ESPECIALLY in a road-race application.

If the OP for some reason is interested in running the KC4, all he would need are the lines to replace the oil cooler bypass hose that came stock on his car. One end goes from the water pump to the cooler, then from the cooler to the radiator return.

Careful with an aftermarket oil cooler that DOESN'T include a thermostatic bypass. Otherwise in the winter, it could take a long time for the engine oil to get up to/stay at operating temperature. Cold oil can be just as harmful as over heated oil. That's one reason the factory oil cooler used the radiator to cool the oil. In cold weather, the warmer coolant will warm the oil quicker, then once at operating temps, the radiator will cool the hotter engine oil.

I have an oil cooler WITHOUT a thermostatic bypass on my car with a temp gauge installed and in the winter it takes a 10 minutes before the oil temp gauge even starts to move, then on a highway run, the oil temp will drop down to about 180, which is about what the engine temp is. During the warmer months its not a big deal at all. I don't drive my car during the winter, but if its for DD its something to consider.

Personally, the added plumbing and potential for leaks etc. outweigh the benefit, unless you are seeing tracktime or someother endurance type of driving.

Are you experiencing pressure drops during hot weather or some other symptom of cooked oil? Have you had an oil analysis done indicating the oil is breaking down prematurely?

Chris

I didn't have a chance to take it to an event last year since I was slowely sorting all the bugs out over the winter time since I did an engine swap during the spring. ( I don't have two consecutive days off, so it's hard for me to drive, locate, and resolve the problem I was having) I do see pressure drops after about 5-10 minutes of normal driving. I do want to switch over to an AC Delco original oil pressure gauge to ensure the readings are right before I get a kit.

I will make sure to purchase an assembly containing a thermostatic bypass. I don't drive the car in the winter, infact 40* or lower and I won't drive it, but none the less, I do start it up time to time to get the fluids moving around.