Kind of urgent: Oil pan/timing cover/gasket compatibility???

[cortcomp]

I have a 66 327 (short water pump orig to my truck) at the machine shop getting final assembly done. The oil pan was beat up and i decided to replace with something stockish. Reading here and other places i learned about thick vs thin oil pan gaskets and that it depends on the oil pan which one you need. So, i bought the following pan and gasket and dropped it off:

http://www.summitracing.com/parts/SUM-G3500X (specifically says for thick gasket)

http://www.summitracing.com/parts/fel-os34510t (specifically says IS a thick gasket)

I heard back from the machine shop and the guy said that (with the motor upside down mind you ) that the gasket is too thick and it won't let the oil pan rest down to start the bolts.

He claims that around 74 chevy changed the timing covers and that the oil pans are the same from 50-whatever to like the 90s and i just need a newer timing cover.

Now, from everything i read (and i'm a pontiac guy so this is all new to me) the timing covers are the same except for details like timing pointer, etc. and you just need to match the oil pan to the gasket. The guy has built literally hundreds of strong running local circle track, racing, and stock motors, and has more experience than i've been alive. To complicate things, he had an old cast racing cover or some brand or another, and threw it on real quick, and the pan went right into place.

He recommended something like this (no chrome, but you get the idea) but i don't like the verbage about maybe needing to shim the short water pump out to clear the cover? Are there issues with going over an older timing set? Do cam buttons come into play?

http://www.summitracing.com/parts/su...make/chevrolet

In pontiacs you pick a 9 or 11 bolt cover and you put it on and done. There just is no oil pan/gasket/timing cover differences except where the drain plug is. This is all kind of too much to learn on a busy friday!

I have a rehearsal dinner tonight and a wedding mid day tomorrow, so i have a narrow window of opportunity to get the right parts to him this weekend. I would appreciate any input any of you guys have.

[chevy_mike]

My understanding and how I have done is, you place the pan on a flat table and measure the height from the table to the gasket point on the highest part of the front. This measurement will tell you whether you use a thick or thin type gasket. Timing covers are the same (outside the pointer location, if using ones with a welded tab). The pan always dictates the gasket type.

I don't have the measurement off hand of the pan to table but that should be found via Google.

[cortcomp]

That is exactly what i've read, but then again his second timing cover shouldn't have fit then, and summit specifically stated that pan was for the thick cover (no that they've never been wrong.)

[chevy_mike]

If I am reading your first post right, he had a cast timing cover, not a stamped steel one, correct? The cast one could have been made for a specific problem, pan or gasket thickness. I know for racing applications, some cover have been made over the years that would allow you to pull the cover (and then cam) without having to loosen the oil pan.

A factory type cover, the oil pan will dictate the gasket. Does have have another stamped steel timing cover to test with?

[cortcomp]

I stopped tonight and dropped off the thin gasket and saw what he meant. With my oem timing cover on and either thick gasket, either oil pan wouldn't fit with that gasket (both are 2 3/8 from flange to face which would make them thick gasket pans).

His aftermarket one had no timing piece of metal on it, was stamped steel, and was stamped midwest motor works. It looked pretty normal, but the lip where the seal rides is a little more "deep" into the cover and it would work with the thick gasket and either pan. We didn't open the thin gasket because i had to be at that rehearsal in 15 minutes.

He has a summit plain steel cover he's supposed to have gotten tonight to test fit, we'll see how it goes. I don't see any reason not to use the thin one piece gasket if it seems to line everything up, but i'm just frustrated that going by the "rules" and referencing part numbers, and still come out confused.

[chevy_mike]

Weird for sure. Be interesting to hear what happens.

[Captainfab]

I agree that the oil pan is what dictates the thickness of the seal to use. The timing cover seal groove should be the same on all OEM stamped steel small block timing covers. Now, aftermarket timing covers could be a different story. A pan with the 2-3/8" measurement at the front should use the thick seal. The pan for the thin seal will measure 2-1/4".

[cortcomp]

That is exactly what i had thought, but i'm guessing at some point maybe they made timing covers aftermarket to use the thin seal on a thick pan or something?

I haven't heard back yet (he knew i was tied up all weekend) but he should have a plain, $9 summit timing cover in his hand to test with both gaskets and oil pans. The one on my engine looked original from design and pointer and the way the lip on the bottom was welded all the way across and not spot welded, but i did witness it with my own eyes that the pan we measured took a thick gasket and wouldn't sit.

I'll post back, i'm sure he'll call tomorrow and let me know what combination worked.

[cortcomp]

I never followed up on this, but he used the new timing cover, i tacked on my oem timing pointer and painted, and the new oil pan and the thick felpro gasket. Used longer bolts to suck it down, then switched to the two short oil pan bolts. He felt the gasket was like .050 too thick. About 500 miles and no leaks.

The OEM timing cover/thick gasket/thick gasket pan would have worked, but the seal holder edges were cut for someone to sneak the timing cover back on without disturbing the pan, and i didn't want to mess with that, easier to move the pointer over, paint, and look OEM.