SSI's and Heat

CHILI · CHILI's Garage

I've read that SSI's make 911's run cooler, but mine seems to be running hotter. I suspect it's because the vertical portion of the heat jacket is RIGHT in front of the oil cooler, thereby cutting off air flow to it. My 3 in 1's with the stock exchangers were more towards to wheel, so the airflow was better and the heat jacket wasn't RIGHT by the oil cooler.

Does anybody maker or has anybody seen a scoop or something that will help get air to the stock oil cooler? I don't have a fender cooler, just the one on the engine.

diy83sc · 03-09-2004, 09:39 AM

Don't you have to richen the mixture some? I don't know for sure, but I had to do this just by swapping out a cat for the euro-pre muffler.

CHILI · CHILI's Garage

Quote:

Originally posted by diy83sc
Don't you have to richen the mixture some? I don't know for sure, but I had to do this just by swapping out a cat for the euro-pre muffler.

I don't think so because there's no cat on my car. It was just a simple swap (well, maybe not simple, but a swap nonetheless).

autobonrun · autobonrun's Garage

I had a Cat BP for about 15 years but had to richen my mixture when I replaced it with SSI's. The change in mixture was purely to make the car run better. I can't tell if the car is running cooler however.

speeder · speeder's Garage

The engine oil cooler does not depend on ambient air flow on any 911, it is cooled from the cooling fan/shroud. Here is a picture, hope this helps, as you can see, *no airflow from front*. Those Germans were more clever than you are giving them credit for.

Now the oil line next to the SSI, on the other hand.......

Jim Sims · 03-09-2004, 10:19 AM

When was the last time the air side of your engine mounted oil cooler was cleaned? How about the top of the engine and the cylinder and head cooling fins? Check to see that all of the ducting on top of the engine is in place. Cheers, Jim

speeder · speeder's Garage

Correct mixture is very important on any motor, and particularly air-cooled ones since cylinder head temps can skyrocket w/ a lean burn, but this is not related to your original question. I urge everyone to have your mixture checked by exhaust sniffer, it can mean the difference between a teardown and driving.

john walker's workshop · 03-09-2004, 10:24 AM

what is your temp now? it may be hotter, but it may still be considered in the normal range.

Steve W · Steve W's Garage

Chad, check your mixture - the difference between lean and rich can be as much as 20-30 degrees in oil temps. Not sure if you have an O2 sensor, but just as a quick way to check, read the voltage off your sensor while cruising at steady speed - should be between 0.2 and 0.7 volts, higher is richer. If you're seeing 0.1 and lower constantly, you're too lean.

CHILI · CHILI's Garage

Thanks for the tips, guys! I'll crawl under it and check it out.
John, it's still in the "normal" range, but my car has always run cool (esp for a 2.7) and that's the way I want to keep it!

I don't have an O2 sensor. Not much more than a motor strapped to a car! Hahaha

No smog equipment, no O2 sensor, no cat. It's a 74, so no need to smog anymore. Not that it had much smog equipment anyway.