drive it

I've added an aftermarket cooler (headered design) and mounted it in front of the rad. at an angle....it must of helped but!
Even when the coolant temp is 190 the oil will be 230's when runnin' down the freeway on a 95 deg. day!
Going up the hill it hits 250's?! while the coolant temp is 220's!?
I thought the real engine oil coolers would make a bigger diff-but the engine oil still runs 30 to 40 deg. above the coolant temp....is it just me?
Thanks for any input! And let me know if your's runs those temps without an additional cooler!

REW89

I have an 89, 6 Speed, 53K miles, with the facotry oil cooler, running Mobil 1 10W-30 and a 160 thermostat. My oil/water temperature differential is rarely above 25 and on a day like you describe with continuous crusing, my oil would be about 10-15 hotter than my engine.

Bob White

Rob90

I also have the same temp spread as REW89 with the factory oil cooler and Mobil 1.

SLEV89

i was monitoring mine closely the other day while cruising around in city traffic;
it hovered between 81C and 87C (178F and 189F) depending on the load - relatively close to my coolant temps
80F ish outside
stock system

js0308

My oil temps normally get up to 240-245 with coolant temps around 220. This is on a car with 150K in 100 - 110 degree temps outside. Im running Mobil 1, I had the same temps with regular oil before switching to Mobil 1. :seeya

vader86

My oil rarely gets above 210, coolant averages about 180.

160 thermo and reprogrammed chip to make the fans come on at 195

87greenwoodvette

I have an 87 with automatic and a 190 stat. Going down the freeway with outside air temp in 90's my temp runs 210-220 depending on if im pulling up a hill or just cruising along at 80. I believe a lower stat (160) would be better for both oil and engine temps.

tkrussell

I had an 18 degree difference (191 Oil/ 173 Water) on a stock LT-1 in cool weather (160 stat). In 100 degree weather in traffic, the difference was 30 degrees, and on the highway at high throttle, it rarely got above 40 degrees difference (230 oil/ 190 water). This with no oil cooler.

One has to wonder if your oil cooler is getting good air flow. I know it sits in front of the radiator, but is the air just going around it rather than through it.?

Also, with the age of your Vette, have you really cleaned and flushed your cooling system? I got a load of crud from mine after only 5 years, and the engine ran a lot cooler.

Just some thoughts. Good Luck!!

c4cruiser

My 92 LT1 (no cooler) oil temps with Mobil-1 are typically 215-230 on the freeway and atound 250 on the track.

At the Monterey Del Oro event in California last month, there was a C4 seminar featuring Dave Mclellan and Doug Rippie who talked about how the C4 L98's and LT-1's handled water and oil temps. They both said that these engines can easily withstand oil temps into the 290 degree range. Rippie's race motors regularly saw 290 temps and they never had problems with basically stock-block race motors. The ZR-1 that held the 24-hour speed record at over 175 was a regular production-line motor (actually it was a rejected motor as it had some bad paint work on it!!) with no mods and it never reached over 270 degrees. In that motor and record attempt, they used synthetic oil and changed oil at the recommended intervals during the record attempt.

The big reason for the factory dropping the cooler used on the L98 from the LT-1 motor was the chang to synthetic oil. They felt that the cooler was not necessary with the Mobil-1.

I would think that the temps you see are nothing to really worry about. Change oil often, and always use a high-quality filter such as the Mobil-1 and consider using a synthetic oil for increased protection.

drive it

I guess without an airflow chamber I can't say for sure how much air the oil cooler gets.....as for the engine-it's a fairly fresh (35k miles) rebuild 406 with new be-cool rad and dual shrouded 11 inch spal fans. Yup I did drill the holes on the heads for the 400 block too!
I just thought that an oil cooler would make a lot bigger diff in temps...but it is a 406 with a SC......
c4cruiser-thanks for the supporting data that I'm not gonna cook it! And yes, I'm already running synthetic.
Thanks for all the replies and info! Also anyone with a SC that has their temps info?

VETTENV

I just drove 3,000 miles on the interstate and my oil temp never got above 215.

cash's90

My '90 has analog gages for oil and water. Should I assume the readings to be linear i.e., 180 degrees would be half way between the 100 degree (low) mark and 260 degree (high) mark?
How do you folks with analog (1990 and up) gages get so specific about temperatures?

ol,RJ

I've been watching my oil and water temps for awhile now on my 406ci.

cruising down the highway in 85+ degree weather, water at 168-178deg (160thermo with 2 bypass holes) oil runs 208- 218deg. but I'm not running full synthetic oil at the moment.
RJ

hngacurv

On an 90 deg. day my oil runs between 210 and 220 depending on traffic. In the book Max Performance Chevy Small Blocks by David Vizard he claims that if "you increase oil temps from 180 to 200 on a typical 300 hp sb it is worth about 5 hp and if you lower coolant temps from 200 to 170 it is worth another 6 or 7 hp."

dscottr

My oil temp is usually 10 to 15 degrees higher than my coolant temp (205 to 210 Oil temp). Mobil 1, Ofcourse. 160* powerstat

SPD DMN

Mine usually run 20-30 degrees higher than the coolant with dino oil in the LT1. Just switched back to synthetic so we will see if there is much difference.

Greg Johnson

90 degree day, stock LT1, 190 coolant, 215 oil.

Greg

c4cruiser

The 92 and later cars also have a digital display for oil and water temps. Not sure about 91 cars.

FrankLT4CE

My 96LT4 with no add on cooler but with a 160F thermostat and Hypertech (fans set to factory settings) runs about 165 f in 40 f weather and about 185 in 95 f weather on interstate. If I get in city traffic it might go as high as 215f. FrankLT4CE

jcazin

I always make sure that I'm over 212 for awhile, to burn up the normal condensation......