blownboat

What kind of oil pressure are you guys running in your stock 502 mag mpi at around 3000-5000 rpms. Just curious , Thanks

mcollinstn

You should see at least 40 psi.

Rule of thumb is 10 psi for every 1000 rpm, but a lot of merc stockers don't show that much.

paradigm shift

MC is rigth on a usual. Mine ran 55- 60 psi.

Not sure why you are asking but just curious from your ID. Is this motor blown? If it is there is a major increase in heat load from 3000 to 5000 rpm.

blownboat

Yes you are correct, it is blown, the manual said 40. Every stock big block chevy I have had usually has more than that when throttled up. Mine is 35-40 and I have not thrown a mechanical gauge on it yet.

Dave M

I have a stock 454 Mag MPI and runs at 40 psi. My gauge never reads higher than that even at 5000 rpm. The engine runs strong, no problems.

28Eliminator

Mine is the same as Dave M's. Right around 4000 no matter what rpm's. After a hard run it idles at 20 and I usually try to keep it above idle to help the oil cool down before I let it idle. I probably wouldn't be concerned with 35-40 on an electric gauge. I agree, I have done a lot of older 454's and always had 55-65, but I guess that is how the gen 6 502 is. All of my friends 502's are the same, but it hard to get used to.

blownboat

Well I was not to concerned with it. It is nice to see that we are all running about the same. My gen 6 in my 98 gmc runs at 40 lbs at idle and 60lbs at 2000 rpms. And that is with a thinner motor oil.Hmmm

madbouyz

After reading the above I guess I was'nt the only one wondering all this time.
Same situation .. 98/99 502 mag Never seen over 40 psi. most of the time runs around 35 or a tad higher. Guess I can stop worrying now .

mcollinstn

Can't trust the reading on an electric gauge. Might be spot-on but the point is that you can't trust them.

Always good to have a decent mech gauge on the motor where you can pop the hatch and compare readings when the elec on the dash causes you concern.

red thunder

Dave M,
My stock 454 mag show only 40lbs no matter what. I had mechanical gauges installed to verify. They show 56lbs. That made me feel better, but i still what to see it on the gauges. The port motor gauge has finally moved up to 50+ lbs. Starboard stuck on 40. I think either its a sending unit or gauge issue.