tim72

The melling repesenative told my engine builder there pump for an Olds 455 will not push the presure past 40 PSI. He said they have had issues with this for some time. Case in fact my motor which would never go past 40 psi no matter what rpm. Any of you following my posts know the issues I have had with oil pressure. To me this is BS from Melling. Why the heck would they even bother selling the pump? Guess I know why everybody is shiming the spring? I think we all ought to do a class action suit against them. The melling rep warned against shimming the spring as it will fail maybe at an in opertune time.
Anyways now that we all know this, what pump are you guys using out there besides the melling piece of Junk? Go back to the original GM pump? What pressure does a stock 455 have at 3000 rpm? What psi is the 455 at idle? My factory book states the idiot light is set at 2 to 7 psi at idle. That has to be on the low side of security in my opinion.

Tim 72 PO'd

citcapp

I am no expert on oil pumps, but I run a stock melling high volume oil pump in my built Olds with correct bearing clearances and I idle at 25 and run down the road at 50 psi. There is a lot of variation in oil pressure as you will here about soon. Lots of factors to consider. Others will chime in soon and mention things like installing washers under the spring to increase pressure. Standby

compedgemarine

on a 350 I had in a 70 Cutlass when up to temp it idled with 8-10 psi and at hwy speed never went past 30-35. always seemed low but it ran that way for years till I sold it and it always ran perfect. after a short time I removed the gauge and just hooked up the idiot light and never worried about figuring if it blew up so be it. it never did even though I ran the crap out of it.

dc2x4drvr

Blueprinted Melling high volume...bout the same as ctcapp. Find another builder.

64Rocket

I have never heard about that. I have a Melling pump in almost all my builds. I have had my pump shimmed and all the right clearances and restricted cam brgs and lifter bores. 70 psi cold and around 45 psi at idle. Has ben that way for the last seven years.

Gene

tim72

We shall see as I called the tech at Melling. did not get much favorable info from him. Seems nobody wants to take responsibility.