ezstriper

I would run that pump out of the box...BB chevy does not need massive amounts of oil pressure...all you are is wasting H/P driving the pump harder, raced them for years, ran as low as 15 @ idle with 1000hp...my .02 Rob

supermx96

What was your pressure at WOT hot oil?

I see 20-25 psi idle hot and 48-50 WOT hot with the melling 10778 pump, HP spring, no shim on the spring.

Budman II

iTrader: (1)

Is that hot reading after a hard run, or just when up to temp? Do you have an oil temp gauge on it?

supermx96

Thats after a couple minute runing at 4000 rpm or even after a hard run, in cruise speed hot engine 3500 rpm oil pressure is at 58 psi and the oil cooler is cold, after a couple minute at 4000 rpm the oil cooler come hot and oil pressure drop at 48-50 psi.

Don't have oil temp on it now but i know that my pressure drop as soon as the oil t-stat open and pass into the oil cooler like that the cooler is too restrictive.

Budman II

iTrader: (1)

Super, you may have already read through this epic thread, but if not, it is very educational, and it may hold the solution to your problem. It sounds like you may have a restriction in all of the oil lines, remote filter, etc. Either that, or you need a larger oil cooler. I would get an oil temp gauge on it pronto to see what is going on there. Another thing to check is to make sure (if it is a Gen VI) that the correct bypass is installed in the filter pad.

Also, do you know for sure that the light spring was not installed in the oil pump?

Here is the thread - a wealth of info => http://www.offshoreonly.com/forums/g...-hardware.html

ezstriper

also remember the stock merc, oil cooler, filter adapter, all lines/fittings are way to small period on anything up to a 500HP, not sure on the higher HP engines...