jrcc2002

iTrader: (3)

I'm looking for an oil pump that can keep good pressure at 6,000 rpm. My 383 has roughly 5,000 miles on it. A very rough and abusive 5,000 miles. I've noticed that every once in a while the gauge will drop to 40 psi when I get to 6,000 rpm. That is on the factory gauge and an autometer mechanical gauge. When I built the engine I installed a Melling high volume oil pump and kept all oil clearances for the mains and rods at factory specs. Every time I have the engine out of the car I always pulled the pan off and checked the bearings. They have looked pretty good until now. The bearings closer to the front of the engine are not getting the oil that they should be. As you can tell from the picture. This was the worst bearing in the engine. So now i'm trying to find a new pump that will keep up. This engine has always seen most of its life at higher rpms but I need to take care of this problem before it hurts the crank or worst. So far it hasn't done any damage to the engine but i'm sure if I don't get this taken care of there will be problems. Any ideas? Part numbers? Suggestions? This is the first small block chevy that i've really had this kind of oiling problem with. I'm using the Canton oil pan for LT1.

ADM

Why did you buy high volume instead of high pressure?

myltwon

iTrader: (1)

well he does have a canton hv pan (looks like)

as for pumps I've seen most people seem to have the best luck with a stock/upgraded stocker. I can't remember the last time I've seen an OEM pump fail on an LT1 outside of the pressfit pickup falling off.

jrcc2002

iTrader: (3)

I have a bolt on canton pickup tube that I have checked the clearances on. At first I used a high pressure pump and I had an oil pressure problem so I swapped it out for a high volume which also had higher than factory oil pressure at lower rpms and it has the same problem.

jrcc2002

iTrader: (3)

What kind of pumps are the autocross guys using (besides dry sumps)? These engines have to run high rpms for a longer period of time.

monster81

how bout this standard volume/high pressure OP from GMPP, it comes with the white spring built-in
http://www.summitracing.com/parts/NAL-12555884/

jrcc2002

iTrader: (3)

I don't know that another high pressure pump would solve my problem when I've already bolted on 2 different ones just like that.

jrcc2002

iTrader: (3)

Can an engine builder tell me if 3/16" is not enough clearance between the oil pan and pickup tube. A guy on another site is tellin me there should be a 1/2" of clearance. That leaves a lot of oil in the bottom of the pan. Thats my opinion.