well thats a given the correct way is pistons rods sleeve and so on. This is just something I heard about the Gasket I supose droping it one point wouldnt hurt as much as droping it to 8-1

 

8:1 won't "hurt" if you have 25+psi of boost. The bores may crack at the bottom of the block, but it's not from the headgasket. It's from the insane amout of power a F20C makes on 25psi.

A thick headgasket lets you run more boost on a otherwise stock bottom end, that's it. The increased power produced from running more boost is what can cause engine failures.

Flathead Fords have to run 8:1 because any higher CR restricts airflow from the valve to the chamber.

Top Fuel Hemi's run 13:1 and 55+psi of boost, making 5-6000hp, and last 4 seconds, maybe.

A domestic iron headed V8 can usually ony run 9:1 on pump gas without detonating. They have huge bore sizes, and not as efficient cylinder head flow.

A small bore, aluminium headed engine (F20C) can much higher CR (On pump gas) due to the increased cylinder head efficiency, and smaller bore daimeter.

 

well if your running 25 psi on pump theres something wrong with you. Im shooting for 400 on pump and close to 5 on c16 with my set up im doing

 

I know of several turbo cars running 20+psi on pump gas. If the engine is designed for it, it's not unreasonable. There are a few STi's in my neck of the woods doing so.

Some diesels can run 90psi+ of boost, but it's also impossible to have detonation with a diesel.

 

or your turbo is too small

I am planning to run 25psi on pump gas with my Trust T67 turbo, when my fuel system upgrade is finished. This is only possible because we recently have pump fuel with 98 octane rating and 10% ethanol. The ethanol allows more boost + timing compare to ordinary fuel. However the fuel consumption is a lot more than ordinary fuel due to less specific energy per litre

 

Actually, detonation (or compression ignition), is what powers diesel engines. The fuel ignites, or "detonates" if you will, upon injection into the cylinder.

 

Exactly.

 

Back to the original question, stock head gasket with copper spray.

 

cometic head gasket with arp bolts

 

What size gasket are you using w/ the ARP bolts?
And how's it holding?