I recently picked up a 94 stock (at least it appears that way) Z-28 and I just had the Oil/Filter changed with Valvoline 5w30 dino oil. My question is this...what is "typical" oil pressure for these LT1 engines...since I'm a greenhorn with these engines? Currently mine is running 18 to 30'ish psi, with 18'ish at stop lights, and 30'ish on accleration. Since the stock guage displays 0 to 80 psi...the readings I'm seeing seem a bit on the low side, my LS1's were somewhat higher...of course I know I'm not comparing apples to apples. Do I have anything to be concerned with? TIA for any comments or suggestions.

 

That is normal...LT1s usually have quite low oil pressure. Mine ran as little as 10psi when it was hot and ran like that for years. The fluctuation is normal too, that is what you get when you run the oil pump off of the cam through a oil pump drive. If it bothers you run thicker oil...just listen to make sure that it is not so thick that the lifters have a hard time holding their prime. Welcome to the forums!

 

My oil pressure has always ran in the high 60's while im driving and in the 30's-20's while idling...

 

I believe the specs on LT1 lower limit is something like 6 psi at idle. Anything better than that meets their specs. Oil pressure varies depending on weight of oil, outside temps, wear on engine, idle speed, oil sending unit age, etc. The one I bought runs mid 40's while driving and drops to around 20 at idle on warm engine.

 

On a cold engine, my LT1 runs between 60-70 at moderate road speed. After the engine gets hot, it generally doesn't drop below 30 at idle, even in extreme temps. That's with 105k miles on the clock. Your pressure is a little low, but not critical.

 

Isn't the rule of thumb every 10psi of oil pressure for every 1000 rpm?

 

Thanks everyone...I appreciate all of the info...sounds like from all the responses that these engines operate all over the spectrum of 0 - 80 psi. I guess the key point is that you at least have some psi...none is not good! This morning the Z was running at 40 psi, out of a warm garage into the 20's here in central Indiana...that's the highest I've seen it run...so who knows! Thanks again, you guys are great!

 

ive been wondering this my self for a while since mine is barely above the red on the gauge at an idle after it warm. when im driving mine is usually at the half mark. seems kinda bad to be that low to me

 

Other peoples oil pressure being all over the place depends on how well the engine was maintained (and treated) by the previous owners. The LT1 in my Vette came with Mobil 1 in it from the factory. Was synthetic oil kept up by the previous owners as I do though? Not a clue. But I'm confident the engine was cared for pretty well, as the heads are as clean as a whistle underneath the valve covers.

 

yeah ive had a bunch of 4.0 jeeps and seens ones with lots of miles running better, just from proper maintence. the problem these days is people just dont do the required/recommended maintence. running a motor low on oil for too long, so many things can just tear up a motor.