Rockn-Roll

I'm selecting the parts and stuff to order for my rebuild. I'm looking at the Mr. Gasket Chevy 283-350, 1957-74, Includes Steel Head Gaskets Jeg's part #720-7104. The other set reads, Chevy 265-350, 1957-75, except 305 Jeg's part #720-7100. It's almost like Mr. Gasket is saying that 1975 head gaskets were not the embossed steel variety, but I have two such head gaskets from my original engine...duh...any comments? Should I replace with the steel gaskets even though it doesn't list 75, or buy the other set since it has my year listed. I pretty sure I'm getting the steel gasket unless someone has a very good reason not to.

Dalannex

Put the steel headgaskets in the scrap iron pile and get a real headgasket. ;) I don't know about the new ones but in the past I took out several steel headgaskets that were leaking and replaced them with the black gaskets. In short, i don't like them. :lol:

-Justin

zwede

If I'm reading this right you're ordering a gasket set. The oilpan changed in 1975 and a 74 pan gasket will not work on a 75-up oilpan. The front seal between pan & timing cover changed.

No difference in headgaskets, though, so you could get the 74 gasket kit and replace the oilpan gasket with a 75-up, if you really want the early head gasket.

markdtn

I didn't know you could still get steel head gaskets. Are you sure it's not a composition gasket and the difference in the kits is the aforementioned front seal?

442olds

Multilayer steel gaskets are made by several of your top brand name gasket manufacturers. They are literally the best seal you can get without stepping up to a copper gasket which requires a lot of extra machine work and headaches to get right.

Check out Cometic Gasket company, they can make you anything you could ever want. Their head gaskets are a coated multi layer stainless steel headgasket.

Other things you will want to consider when purchasing head gaskets are the bore size of the gasket and the thickness. You want to try and keep the bore size only slightly larger than your actual bore and if possible pick a gasket thickness that will get you the closest to .035 to .040 piston to head clearance.

Rockn-Roll

Hmm, if the oil pan changed in 75 then why doesn't Mr. Gasket show a 75-up gasket kit...the kits are either 57-74 or 57-75. Man, half of rebuilding an engine is sifting through all the confusing and convoluted product marketing and packaging information just to get the right parts.

Fevre

It may be that the change took place sometime in the 75 model year thus the overlap. The gasket kits I have bought tend to have a 4 peice oil pan gasket with 2 diff front seals, one thick and one thin. Now if you are going to a one peice gasket then you def need to know which one you need. Think the thin one is about 1/4" while the thick one is 3/8 or 1/2 inch, sorry don't recall the exact thickness.

SCCACFC

The steel or (shim) head gasket was used by the factory back then. The steel gastet is thiner than say Fel-pro blue and is worth about 1\4 point of compression. If you go back with the OE gasket coat it with Copper Seal, the spray type is better. The good high-perf parts houses like Barnett still stock the shim gaskets, in fact I think they sell different thicknesses to adjust the CR.
Good Luck

KenSny

Or just by the gasket you want. After all it's still a Chevy 350. All you need to do is make sure that the bore size is correct and go get steel shim gaskets. I have seldom purchased gaskets in kits unless I was sure I wanted all the generic stuff. Sometimes it pays to get the parts individually.

For example: Use the one piece oil pan gasket instead ot the four piece standard set. Much better......

Ironcross

The steel head gasket is still available at any GM dealer. The one piece Felpro oil pan gasket is a wise choice as others have also stated. Part number OS34510R. :thumbs:

cardo0

:eek: The steel shim gasket provides a little more compression (desperatly needed on L48) with that 0.015” compressed hieght. It also provides a good “Quench Hieght” with the stock block deck hieght for better everything – fuel mix, fuel burn and a few ponies. I like the Fel-pro gasket as it’s a little tighter dia.. But you need to get the block and heads cleanie clean (no old gasket for no leaks) enough to see all machine marks and use some good sealer – Permitex (spray). :thumbs: