What brand oil pan are you using and where'd you get it? I may be in the market for a stock capacity oil pan to fit a 1 piece RMS gen 1 block real soon, as it is starting to look like a junk pan is the culprit. I'm 95% certain I bought a pan for a 1 piece RMS motor, but this was well over a year before the motor went in the car, so I am going to dig out the paperwork when I get home next week to check.

Here's my dilemma, i built up a 1 peice rear main 350 for the 85, and it likes eating oil pan gaskets. In 65 miles, i've toasted 1 Felpro one piece gasket (looked like the crank snagged it), and 2 Rol gaskets (first was to gas being dumped in the lower end while I was gone, second I haven't pulled apart yet to figure out).

To knock off one question, I have an open PCV system.

Here's a few pics I have uploaded, there's more on the camera of the first two gaskets.

Felpro



Rol #1


Any advice, tips, or recommendations? (aside from putting the 305 back in)

 

A one piece RMS pan is different than an older 2-piece RMS pan. The difference is back where it goes over the rear main and I doubt you could interchange them without there being an obvious problem upon assembly.

It definitely looks like the gasket is squeezing into the crank area and getting chewed up. I'm not sure how that could be happening, though, if the bolts near that area are capturing it through the holes in the gasket rails. The way that gasket is squeezed out around the lip of the "half moon" in the last photo, though, definitely ain't right.

Maybe go out to the junkyard and rip a stock pan off a factory 1 piece RMS V8 engine and compare it to what you've got right now. See if anything jumps out at you.

FYI- always oil the gasket a little around the half moons (both sides) before installing the pan and tightening the bolts. You don't want the pan to "grab" the rubber and tear at it as the pan seats home. You need it to slide and compress the gasket, not tear at it.

 

I've got the felpro 1 peice rubber one on my 88. Ive had the motor out several times and reused it each time. Still looks like new. Stock oil pan.