283 and 307 Steel Shim Head Gaskets

[Timothy B.]

This past weekend at Fall Carlisle I purchased a GM head set #3931595 which after checking is for a 307 chevy. I have two questions, first is the head gasket the same as 283, it measures approx 3 15/16 hole size? I am not sure the GM part # of the head gaskets that make up this kit and the plastic bag has never been opened.

The second question is about the intake manifold gaskets and they are cut with the round humps and the rubber with tabs and GM but will they fit the 327 engine? They sure look the same but I thought someone here may know for sure.

TIA, Tim

[Joe L.]

Re: 283 and 307 Steel Shim Head Gaskets

This past weekend at Fall Carlisle I purchased a GM head set #3931595 which after checking is for a 307 chevy. I have two questions, first is the head gasket the same as 283, it measures approx 3 15/16 hole size? I am not sure the GM part # of the head gaskets that make up this kit and the plastic bag has never been opened.

The second question is about the intake manifold gaskets and they are cut with the round humps and the rubber with tabs and GM but will they fit the 327 engine? They sure look the same but I thought someone here may know for sure.

TIA, Tim

Tim------


The 283 and 307 head gaskets should be the same.

There were only two basic types of small block rubber manifold end gaskets-----the type with the locating tabs on the sides and the type with the locating
"pins" that insert into holes in the block end rails. If your block has no holes on the end rails, then you require the type with the tabs. I expect you have what you need.

Manifold side gaskets can differ. The primary difference is the heat cross-over passage. Completely open was the configuration used for Corvette small blocks through at least 1970. Other small blocks may have used cross-over passages blocked or partially blocked by stainless steel plates. If your side gaskets have the plates, simply remove them and the gaskets will work fine for your application.

[Timothy B.]

Re: 283 and 307 Steel Shim Head Gaskets

That's great news, Joe, I assume these GM shim head gaskets differ only in bore size from the 327 motors? The water holes are in the same spots, correct?

[Joe L.]

Re: 283 and 307 Steel Shim Head Gaskets

That's great news, Joe, I assume these GM shim head gaskets differ only in bore size from the 327 motors? The water holes are in the same spots, correct?

Tim-----


Yes, bore size is the only difference. However, I think in later years for SERVICE they may have gone to the larger bore size to SERVICE smaller bore applications. I'm out-of-town right now so I can't check it. There is no difference in the coolant or other passages (unless you get to 400 cid small block or Gen II small block)

[Timothy B.]

Re: 283 and 307 Steel Shim Head Gaskets

Thanks again, Joe, that information helps greatly.