oil pressure

[dfhotlm33c]

406 Chevy, Dart SHP block, scat ultralite crank, Callies h-beam rods, Mahle pistons, wet sump 7 quart pan
.002" rod bearing clearance, .003" main bearing clearance (plus or minus .0002).

Engine has all of 50 laps on it, runs to 7800 rpm.

Melling 10555 pump.

Cold, engine has 95 psi oil pressure (Mechanical gauge routed to standard port on back of block)

Warm (oil temp 210), engine idles at 65 psi.

Too much? I have to drop pan to solve rear main seal leak problem anyways..should I put lighter spring in or leave it as is?

[fastford]

thats a lot of pressure and could hydraulic or damage bearings , its been a while since i thought about the melling part numbers , is that the high pressure pump or the high volume pump ? either way , i would definitely go lighter on the poppet spring....

[dfhotlm33c]

10555 is high volume pump with a high pressure spring in it. I was thinking of going to the yellow spring which has a 58 lb bypass pressure

[fastford]

thats what i would try.....

[stock car driver]

I had better engine parts wear when I went to a hp pump not hv...

I would think at that psi and hv your adding a lot of heat into that oil..

[Krooser]

Seems like a bit more oil pressure than you need.

HV pumps are good when you have a bunch of loose clearances and internal oil leaks... loose lifter bores, unrestricted oil to the top end, big bearing clearances all stack up.

High op and volume do heat the oil... sometimes you have to dance with the devil.

[powerslide]

I had a 10555 on a motor and it would go up to 80 and bypass. Not sure what spring it had but I felt like it was a good compromise I think it idled around 30 hot. I would look into a shark tooth pump with all those nice parts you have in that motor.

[perfconn]

What is meant when someone says "too much oil pressure can hydraulic bearings ?"

[fastford]

wash the coating off in streaks.....which is what ive seen , some might say distort instead.....