[HWYSTR455]

The last iron head engine I did was in the late 90s, and ran that until mid-2000s or so (I've done many Pontiac engines. Many.). 400, 16 large valve heads, surface clean up, TRW pistons, .030 over. It cam in at 9.97 SCR, and that's at .030 over with a .040 head gasket. I've run many large valve iron heads, and don't think any came in at 72cc, but kind of moot.

I did the timing dance on that engine, have what many here consider a 'large cam', and even sprayed it. I purchased thick cometic head gaskets in an attempt to tame it, but never installed them. You could probably search here and find the listing when I was selling them.

If you look at the engine pics of my 'bird from the 80s, you will see i ran an Edelbrock water injection system, it didn't really help.

Many have opinions on quench, but I can argue that since many other manufacturers had chamber designs that had no or little quench, the hemi is a good example. So I don't put a lot of 'faith' into the idea.

The most you will realistically get from thicker head gaskets is about a half a point of static, and if you're at 10.5-10.75 like mentioned, it ain't gonna help enough.

With that said, really the biggest 'issue' with thick head gaskets is potential to failure, not mentioning the need for longer pushrods, thick intake gaskets, etc.

Try it, I'd like to know how it works out. Like I said, once I was going to try it, but realized even for a short fix, it was far less than optimum, and no guarantee it would control det. so I bailed.


Photo - circa 1981, can see the Edlebrock water injection setup.

CORRECTION: 400 SCR was 9.98, not 9.97, just checked.

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