L-98 oil cooler
Thread Starter
Drifting
Joined: Dec 2005
Posts: 1,313
Likes: 2
From: High Ridge Missouri
L-98 oil cooler
I have a '91 Vette and I'm in the process of doing a whole lot of little things that have managed to turn into something big. My question is in '92 when the engine was changed to the LT-1 the oil cooler was removed. GM said this was possible due to the change over to synthetic
oil and lower oil temps resulting. Now if I'm running synthetic oil as well
as a cooling system set-up that should drop the engine coolant temp
to approx 185 deg. Is there any reason I can't eliminate the oil cooler.
Also has anyone else done this, if so any adverse effects?
oil and lower oil temps resulting. Now if I'm running synthetic oil as well
as a cooling system set-up that should drop the engine coolant temp
to approx 185 deg. Is there any reason I can't eliminate the oil cooler.
Also has anyone else done this, if so any adverse effects?
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Lots of us here have deleted the factory cooler with no ill effects.
It does however make longer running oil temp closer to water temp.
After a good run my oil temp will be 10-15 above water whereas before was maybe 5 degrees
It does however make longer running oil temp closer to water temp.
After a good run my oil temp will be 10-15 above water whereas before was maybe 5 degrees
Thread Starter
Drifting
Joined: Dec 2005
Posts: 1,313
Likes: 2
From: High Ridge Missouri
So if I'm dropping the coolant temp by 15 deg that should make up the difference and the oil temp should be approx where it was from the factory, so I'm ok with that. Hey rodj what parts do I need to eliminte the cooler sandwich?
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
"So if I'm dropping the coolant temp by 15 deg that should make up the difference "
What I was saying is that with the cooler the oil temp runs closer to the coolant temp than without.
While since I did it but recall oil cooler has threaded tube that threads onto the regular oil filter adapter mounted on the block.
Only thing to be changed is the bolts that hold adapter on.These have a special head to locate the cooler.Just have to replace with regular bolts , hex head pref for clearance.
Outlet , lower block drivers side needs to be plugged and hose feeding alum line under sump needs to be removed / plugged.
What I was saying is that with the cooler the oil temp runs closer to the coolant temp than without.
While since I did it but recall oil cooler has threaded tube that threads onto the regular oil filter adapter mounted on the block.
Only thing to be changed is the bolts that hold adapter on.These have a special head to locate the cooler.Just have to replace with regular bolts , hex head pref for clearance.
Outlet , lower block drivers side needs to be plugged and hose feeding alum line under sump needs to be removed / plugged.
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
I took my oil cooler off my 85 last summer and my oil temps would consistently go up to 210 and even 225, not a huge deal.
Also, I have an Dewitts aftermarket radiator that cools the car very well, even with my radiator staying at no hotter than 185 degrees my oil temps still went up to 225
But I put my oil cooler back on this winter and now my oil stayed very close to 10-15 degrees hotter than my coolant, which is makes my oil stay in the 185-200 range.
People can say what they want about the factory cooler, but, IMHO, this is a pretty slick small design, solution to knocking your oil temps down 10-15 degrees.
The only alternative is a much larger cooling package with limited mounting positions on our cars for an aftermarket cooler of the typical sizes.
Also, I have an Dewitts aftermarket radiator that cools the car very well, even with my radiator staying at no hotter than 185 degrees my oil temps still went up to 225
But I put my oil cooler back on this winter and now my oil stayed very close to 10-15 degrees hotter than my coolant, which is makes my oil stay in the 185-200 range.
People can say what they want about the factory cooler, but, IMHO, this is a pretty slick small design, solution to knocking your oil temps down 10-15 degrees.
The only alternative is a much larger cooling package with limited mounting positions on our cars for an aftermarket cooler of the typical sizes.
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Race Director
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Originally Posted by Muffin
I am at a loss as to why you would want to remove it.It lives under the car.does its job and doesn't bother anybody.
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
it is a heater, in the mornings its useful to me
otherwise its not really doing much, its too small, but I dont really see a need to do anything with it at all
now if this were a racer, then i'd recommend putting in a larger external cooler and deleting the stocker
otherwise its not really doing much, its too small, but I dont really see a need to do anything with it at all
now if this were a racer, then i'd recommend putting in a larger external cooler and deleting the stocker
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
GM removed the oil cooler (/heater 
) not only because of the change to synthetic oil but also as a cost savings. The cooler and the hoses added up to a fair amount of money and with the Mobil-1 being able to handle heat much better, the cooler was not necessary.
Even with the cooler in place, you can run a full-size oil filter and it still won't stick below the bottom of the oil pan. One problem down the road with the oil cooler setup is that the long metal coolant tube that runs along and under the oil pan to that tee fittig will become next to impossible to find one day.
) not only because of the change to synthetic oil but also as a cost savings. The cooler and the hoses added up to a fair amount of money and with the Mobil-1 being able to handle heat much better, the cooler was not necessary.Even with the cooler in place, you can run a full-size oil filter and it still won't stick below the bottom of the oil pan. One problem down the road with the oil cooler setup is that the long metal coolant tube that runs along and under the oil pan to that tee fittig will become next to impossible to find one day.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by thirdtimevetteowner
I'm looking for one also. Same offer as above.
I'll have to track down the block fitting/hoses, etc. but I'll keep you and PETE K in mind.
Jake
Racer
Joined: Jan 2005
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From: Tucson, AZ. L98-85 AUTO COUPE: 120k MILES: daily driver. SOUND OFF IF YOU'VE BEEN THERE. Ex-Jumpin' Junky-82nd Airborne-2/505 PIR: 1st ID-1/16th Inf: Recon Marine Retread. GOD BLESS GRUNTS.
it is most useful at this time of the year as an oil heater since water temps rise more quickly than oil temps--the heat transfer goes to the oil on warmup, but the down side is that my low coolant temps are hampering me from reaching the ideal 210 oil temp: water temps of 180 give me 175 oil temps during economy driving. but if you are getting on it--and you're oil temps are rising--you will appreciate its cooling.
i don't think that as a cooler, it is as effective as an external cooler. but bringing your oil up to operating temp quickly is a very important function of this "cooler"--especially at this time of the year.
i like it. and i'm keeping mine. mainly because i changed all the hoses last year and i won't have to worry about springing any leaks for a year or few.
i don't think that as a cooler, it is as effective as an external cooler. but bringing your oil up to operating temp quickly is a very important function of this "cooler"--especially at this time of the year.
i like it. and i'm keeping mine. mainly because i changed all the hoses last year and i won't have to worry about springing any leaks for a year or few.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
As I wrote about in an earlier post, a couple of years ago I did back-to-back testing of the oil temps; with and without the cooler installed.
Using the same stretch of Interstate 35E, travelling at the same speed and with the same ambient temps, my oil temps ran about 20 degrees F higher (if memory serves) WITHOUT the oil cooler installed.
Jake
Using the same stretch of Interstate 35E, travelling at the same speed and with the same ambient temps, my oil temps ran about 20 degrees F higher (if memory serves) WITHOUT the oil cooler installed.
Jake