newbie2vette

I recently intalled the newly rebuilt engine on my 1972 LT1, as per the builders standart protocol a new high volume oil pump was used. the first thing I notice was how high the oil pressure gets above idle (70+) on the stock gauge. Then I noticed some oil on the bottom of bell housing. At first I thought it was lose oil pan bolts, I got half a turn on all of them.

Even after doing that several times, I still see oil. After 500 miles break in as recommended by the builder I noticed the oil pressure not so high. So I thought since I am changing the break in oil to go with syntetic oil I might as well get a one piece pan gasket and hope it is the cause for the leak. The oil pressure is back up very high after idle (70+ max the guage). So I am thinking, it was not the oil pan then it must be the rear main seal. Before I pull the engine I thought I would ask my question:
What are the cons for the high volume oil pump? Can high pressure push oil pass the rear main seal? I was thinking of dropping the pan again and replace the oil pump with the original pump.

I guess I am trying to explore all my option before I pull the engine out.

jackson

No hv pump is cause of pan leak.
No hv pump is cause of rear main seal leak.

Most builders install rear main seal ... I suggest any leak there is fault of builder.

Most HV pumps add additional 25% ... I'm not a fan of those.

Melling offers a hv pump that increase only 10% and has a "bolt-on" pickup ... I do like & recommend it.

69 Chevy

You can lower your oil pressure by replacing the spring in your oil pump to a weaker one.

7t2vette

High volume oil pumps are not needed for the street.

Replace it with something like the Melling 10553, which is standard volume, high pressure. It comes with a different spring to lower the pressure if you want to.

http://www.summitracing.com/parts/MEL-10553/

commander_47

Be careful with HV oil pumps. They will drain your oil pan lickity split.

Usually only used in race cars with large pans.

qwank

Most people get High Volume and high pressure pumps mixed up. Its possible he put a high pressure pump in. But like already said, you can usually just change the spring and get the pressure down.

7T1vette

Engine builders make a 'standard practice' of installing a HV oil pump on rebuilds...because it makes them more money!!!!!

Installing a HV oil pump, without other associated items, is just a waste of money and the excess fuel to run it.

LB66383

I assume you're already aware that you don't have to pull the engine to drop the pan and replace the pump and rear main seal.