Oil Temp Woes
Thread Starter
Advanced
Joined: May 2021
Posts: 97
Likes: 8
From: Lee County, Florida
Oil Temp Woes
Trying to get a good idea on acceptable oil temp, 85 Corvette, minor intake work, long tube headers, full exhaust, tuning it myself. Did a shroud cleaning maybe 6 months ago, temps normally driving will be anywhere from 20-40 ish degrees within coolant temp until I get on it, upgraded liland 2 row larger all aluminum radiator, 180 thermostat, temp will stay around 225-230 at 80 mph, 2400 rpm, when I really get into it "on private roads" up to 120-130 I'll see it get as high as 240 if not more. I've seen it get as high as 258 at steady speeds of 130 or so. I will admit I am running without a knock sensor and tuning by ear for detonation on 91, i don't hear anything anymore after pulling degrees where I needed to on the table, but the temps still get hot. Any advice? Not opposed to throwing a cooler on it, but I figured in some high speed situations the car would be fine without it, not like I'm thrashing it at a track day. For reference this car has all its emissions deleted, so no EGR to cool combustion temperatures.
Drifting
Joined: Nov 2018
Posts: 1,752
Likes: 645
From: USA
Trying to get a good idea on acceptable oil temp, 85 Corvette, minor intake work, long tube headers, full exhaust, tuning it myself. Did a shroud cleaning maybe 6 months ago, temps normally driving will be anywhere from 20-40 ish degrees within coolant temp until I get on it, upgraded liland 2 row larger all aluminum radiator, 180 thermostat, temp will stay around 225-230 at 80 mph, 2400 rpm, when I really get into it "on private roads" up to 120-130 I'll see it get as high as 240 if not more. I've seen it get as high as 258 at steady speeds of 130 or so. I will admit I am running without a knock sensor and tuning by ear for detonation on 91, i don't hear anything anymore after pulling degrees where I needed to on the table, but the temps still get hot. Any advice? Not opposed to throwing a cooler on it, but I figured in some high speed situations the car would be fine without it, not like I'm thrashing it at a track day. For reference this car has all its emissions deleted, so no EGR to cool combustion temperatures.
Le Mans Master
Joined: Aug 2017
Posts: 6,940
Likes: 1,490
From: New Jersey
260 is fine for synthetic if you're beating the snot out of it. My 84 would get to 260 with one spirited on ramp pull and would approach 275-280 on cool days under normal driving. If you're holding 260 that is of no concern. Figure the same oil in your sump is run through turbos at much higher temps with no break down. I wouldn't be worried. Figure most high performance engines in the race world are operating in the mid to upper 200s.
That being said, the fix was an oil cooler. See temps right around coolant now regardless of how hard I beat it.
That being said, the fix was an oil cooler. See temps right around coolant now regardless of how hard I beat it.
Pro
Joined: Sep 2024
Posts: 526
Likes: 114
260 is fine for synthetic if you're beating the snot out of it. My 84 would get to 260 with one spirited on ramp pull and would approach 275-280 on cool days under normal driving. If you're holding 260 that is of no concern. Figure the same oil in your sump is run through turbos at much higher temps with no break down. I wouldn't be worried. Figure most high performance engines in the race world are operating in the mid to upper 200s.
That being said, the fix was an oil cooler. See temps right around coolant now regardless of how hard I beat it.
That being said, the fix was an oil cooler. See temps right around coolant now regardless of how hard I beat it.
/post by not a professional mechanic, just an internet dude
Thread Starter
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Joined: May 2021
Posts: 97
Likes: 8
From: Lee County, Florida
I appreciate the responses from everyone on it, I was having minor detonation issues that I'm now resolving with some timing work in the tables, I've gotten it to where up to 100-110 mph I won't see anything above 225-228 which is def an improvement, I should mention even with oil temps over 240-250, I never saw coolant temps above 200 degrees, I had issues running mobile 1 before due to my ring issues and how much I'd burn, I know im due for a rebuild in the future, but this engine still makes 180 psi a cylinder hot, and good power when it runs right. I used a ring additive and changed valve covers so the PCV could be more efficient and it helped tons in terms of consumption. If I hadn't mentioned above, I did just move over to long tubes about a month or two ago, never wrapped them, could that really affect oil temp to that extent?
Thread Starter
Advanced
Joined: May 2021
Posts: 97
Likes: 8
From: Lee County, Florida
260 is fine for synthetic if you're beating the snot out of it. My 84 would get to 260 with one spirited on ramp pull and would approach 275-280 on cool days under normal driving. If you're holding 260 that is of no concern. Figure the same oil in your sump is run through turbos at much higher temps with no break down. I wouldn't be worried. Figure most high performance engines in the race world are operating in the mid to upper 200s.
That being said, the fix was an oil cooler. See temps right around coolant now regardless of how hard I beat it.
That being said, the fix was an oil cooler. See temps right around coolant now regardless of how hard I beat it.
Oil Producer
Joined: Apr 2014
Posts: 9,368
Likes: 2,735
high probability that your cat is plugged.
that said, i had similar but not as high issues even after i gutted the factory cat that was stopped up.
our 84 had the factory radiator. I installed a used, plastic endcap, aluminum rad that was on a parts car, that did it. The temps on the 84 are now very close to a tpi car. For a street car, u could even install an 85+ kc4 cooler. That said, the earls oil to air cooler suggested by 78, is both easier to install than the kc4, new, and will cool better.
be sure your exhaust isnt plugged up! that will lead to oil heating, and will eventually lead to power loss also.
that said, i had similar but not as high issues even after i gutted the factory cat that was stopped up.
our 84 had the factory radiator. I installed a used, plastic endcap, aluminum rad that was on a parts car, that did it. The temps on the 84 are now very close to a tpi car. For a street car, u could even install an 85+ kc4 cooler. That said, the earls oil to air cooler suggested by 78, is both easier to install than the kc4, new, and will cool better.
be sure your exhaust isnt plugged up! that will lead to oil heating, and will eventually lead to power loss also.
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Le Mans Master
Joined: Aug 2017
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From: New Jersey
yeah i used an adapter and some AN line and plumbing and mounted it in front of the condenser. So far so good. In the cool months its difficult to get the oil warm.
Team Owner
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From: Athens AL
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Those temps are too hot for what you have. Stock, oil will get to the 225-235F range and coolant will lag 10-20F behind unless you're in traffic, but if you've upgraded the radiator and still get temps like that I would say something is up. How much timing are you running and have you checked out the main cat?
My main cat plugged up pretty quickly once I put headers on the car.
My main cat plugged up pretty quickly once I put headers on the car.
Thread Starter
Advanced
Joined: May 2021
Posts: 97
Likes: 8
From: Lee County, Florida
Those temps are too hot for what you have. Stock, oil will get to the 225-235F range and coolant will lag 10-20F behind unless you're in traffic, but if you've upgraded the radiator and still get temps like that I would say something is up. How much timing are you running and have you checked out the main cat?
My main cat plugged up pretty quickly once I put headers on the car.
My main cat plugged up pretty quickly once I put headers on the car.