Which head gasket?
 

On an engine with a 4.530 bore which head gasket would you use? FelPro lists a gasket with a bore dia. of 4.540 and a gasket with a dia. 4.640. The first gasket seems a little small. Any gasket material in the combustion chamber will cause hot spots,detonation. But the second one is a little large. Which one should I use/

I am trying cometic this time around.

I have been using felpro for years.
4.540 is what I would run on 4.530 bore.


Gerry

Thanks

Cometics are hot right now. SCE also has a very good composite gasket. Gasket bore you need a minumum of .020" larger then bore.

Chris

Thanks. I had a feeling .005 per side was too close. Just the play in the dowels would possibly allow the gasket into the bore. What about .055 per side. That's the next standard size at Felpro.

FelPro 17048

.055" total is fine, .055" per side will leave to much area for residual contamination of continuing intake strokes. I am not a fan of the Blue gasket, I would check with Cometic or SCE. Do not recommend Corteco or the Blue.

Chris

I gaurantee you there is no play in the dowell holes on the Cometics!!!
They intentionally take some persuasion to get them on :D

I'm running the 4.540 with the 4.530 bore per Cometic.

Cometics are the ones to use. A little higher in price but well worth it.

Thanks. I did a search on Cometics and found them at Pfaff for a pretty good price. How thick are they.

Any thickness you want just about. That's the other nice thing about them.:eureka:

Call Cometic at 440-354-0777

I used Part #C5330 4.540 .040 thickness

They have a +15 thousands built into the bore size.

Just remember when you increase bore size you are narrowing the gasket material between bores. Most head gasket failures occur between cylinders.


Gerry

The C5330 is Mark IV and C5333 is Mark V and VI in the 4.540.

http://www.cvproducts.com/cv/product...?brandCat=1435

Why are they better? I've never lost a felpro yet....

Dyno,
What does a HG do? It seals the head to the block. The blue gasket when the head is removed is very easy to get off. . .now compare that to other gaskets where you have to pry the head off, turn it over to lift the head and other tricks. Those gaskets were sealed. The old Detroit was the best but no longer available.

Chris

You might want to call Merc customer service or the tech center to see how their test runs of the Cometic gaskets turned out. I asked Mel Riggs about them last fall and wasn't overjoyed at his response. I elected to use FelPro again.

Ian, please give me a call at your convenience. 616-738-0474 home, 616-403-3962 cel.

tyler crockett mention he has used cometics for the last 3 years ;)

Cometics as well....