Amyone use these? I am building a 383 plus 150 NOS and all the head gaskets seem to be kind of generic in there applications. Cometic has a variety of thicknesses and bores the gasket to your dimension. I am running new AFR 190 heads. The block will be freshly zero decked and 4.030 bore. I was planning on the Cometic HP MLS 4.030 bore, .036 thick for proper quench. They are EXPENSIVE!! but so is everything else on this build. I really need as much compression as I can get with my combo as the Heads and pistons are also kind of generic in there sizes unless you mill NEW afr heads or modify new pistons. If I went with different pistons or heads I was either under or over where I want to be compressionwise. So I plan on fine tuning compression with these gaskets. Are they any good? Any other suggestions?

 

ttt

 

They're the cat's a$$ according to my engine builder. Reusable multiple times, boost or spray, they hold up. If you compare to replacing every time you have a head off for whatever reason, they're actually less expensive.

 

Don't buy the old AFR heads. Get the new 195. They fixed the design flaws and they flow more than the old 210's. Those should be good gaskets. I have a set of AFR 210 heads that AFR flat milled to 64 cc to get my compression up with .021 gaskets.

 

I have a completely different engine combination, but the Cometic head gasket didn't work for me; they leaked. For my engine, the gaskets were recommended by the head mfg and advertised by Cometic to fit my application.
Cometic reviewed pics of the leak. I think they wanted pics to try to find something wrong with assembly (but they could not), since Cometic would not offer any remedy: no gasket that with guarantee fit; or no money back. Very dissappointed with Cometic about this.
I was pleased with the other gaskets purchsed from Cometic.

 

Too Late. Already bought heads. Went with smaller port to help low end and midrange torque. I have a tripower setup going on it with plate nitrous. The intake ports on the manifold should work well with the ports on the heads and keep the velocity up to help keep the fuel atomized with the tripower. I got a good price on the heads also.

 

I helped build a budget 383 for a friend years ago. He had smoked his 350 with a 175 HP spray system. All he bought was the $1000 Eagle 4340 6 inch h-beam (4 years ago) He had his block surfaced milled so that the Felpro head gasket for aluminum heads and .039 compressed gave him about .044 quench.

That chevelle has had years of 175 shots and 100's of 1/4 miles and never a tear down. The only thing I talked him into was to use the 12 point ARP head studs with his edelbrock VJ heads.

So the FelPro do work in a spray environment. I personnally use FlatOut sealed copper .021 thick. They are about $125 delivered to your door.

what kind of tri power do you have?

 

I Sold My Small base setup last weekend for $1200. I am building a new Large Base Rochester Tripower setup. I bought 2 1971 Chevy 350 2BBls, An Offenhauser Split single Plane 3 x 2 Intake with the large Ports, 2 Reproduction GTO tripower carb tops with side inlets and 2 GTO Tripower Base plates. The center carb is a Large Base Rochester Marine Carb with side inlet and Electric Choke. All carbs rebuilt. I also bought an extended throttle shaft for the center carb to operate the progressive linkage. Should be about 1100 Adjusted CFM. The nitrous is a triple plate system, hard piped, Custom made by 10,000 RPM back in the 60's for a GTO, jetted at the solenoids. It all fits and the nitrous line just clears the thermostat housing and the MSD dist. I am assembling it while the engine is in the machine shop. I have been accumulating parts for the last 2 months to build the new tri power. We will see how it goes. Figure I can fine tune the jetting on this on the dyno. I like the Tripower look, sound and kick in the *** when the end carbs open. I am on the C3 performance forum a lot but my 72 is sold. The C3 guys give me better performance mod advice, and the midyear guys hate what I have done to a 63 split window. This is going in my Custom 63 SWC in the avatar. It has been totally redone since those pictures

 

Make sure you get the correct bore, if you get a gasket with 4.030" hole for a 4.030" cylinder chances are some of the gasket material will hang in cylinder, usually the bore of the gasket is at least .010" bigger. My Felpro 1004'a are 4.190'" and my bore is 4.155, that is .035" bigger.

Personally I would bother with these expensive gaskets, Flepro makes a good gasket for your application at a reasonable price.

 

YEs, I used these on my 406, and do not use a gasket bore the same size as your cylinder bore, you will find out, as I did, that it will hang into the combustion chamber. You will notice most gasket are D-shaped to provide clearance, the Cometic gaskets are round.
This was with the 74cc AFR 190s.

They were good gaskets and I re-used them once with no problems.

 

This is very similar to my situation. How much bigger did you have to go for clearance?

 

The trick to using cometics is having a perfect deck and head surface. They are great gaskets, but even new heads might not have a head surface up to spec. Get your heads checked if you plan on using them and use new bolts with sealer

I love cometics for boosted and nos applications but they are tempermenta. to deck and head surfaces

 

The deck surface wasn't the problem on that build, it was that the gaskets didn't make a complete seal around the water jackets in the block. I have pics of the impressions left by the gasket on the block, and where the leaks occured. The heads were brand new and the block had just been decked by the machine shop according to specs. A gasket retailer told me that he had run into a similar issue a couple of years ago with some SBC gaskets (maybe 400?) but never a BBC like mine. With the SBC he/they concluded that the problem had something to do with "shift" in the stamping equiment during mfg.
The fel-pro gaskets i tried next were also very close to the water jackets, but looked like they may work. It was so close that I wasn't going to be sure until it ran. I think that the Cometics would have been fine if they had been stamped and assembled to fit my engine. The problem i had was that they wouldn't even offer to reimburse the cost of the gaskets that i proved were defective.

 

63Mako: I went with a 4.200" gasket bore on a 4.155" cylinder bore. This is the same size as the Felpro 400 gaskets.

S489: I have to agree with you, Cometic's customer service is aweful. When I ordered my first set I talked to a tech and he said I would have no problem using the 4.165" bore gasket with my 4.155" cylinder bore. When it did not work they did not offer to do anything and I had to order another custom set.

 

VETDRMS: if they just would take care of the customer service side of things, they would be perfect! oh well . . .

 

Yes cometics are the way to go. I use them on all my big blocks

 

2 blown Felpro's, Similar combo with NO NOS! http://forums.corvetteforum.com/show....php?t=1392422