Cometic Zetec headgasket bore size
02-05-2017, 02:53 PM
#1
Regular Contributor
Thread Starter
Cometic Zetec headgasket bore size
I want to put a cometic head gasket on my Zetec Turbo 2.0 (ST170 bottom end, blacktop head) but the standard cylinder bore is 84.8mm and the Cometic gaskets are 87mm bore, why make them so large?
That leaves 1.1mm gap around the top of the cylinder to the gasket, doesn't that just let it get nearer to the water flow? Am I over thinking it?
I know Ford do a 1.8mm thick gasket for the Focus RS, but they are hard to get (paid £130 for the last one!) but I've had my head skimmed and looking at the 2.0mm (.080')Cometic to get the compression ratio well into the area of safe to turbo.
That leaves 1.1mm gap around the top of the cylinder to the gasket, doesn't that just let it get nearer to the water flow? Am I over thinking it?
I know Ford do a 1.8mm thick gasket for the Focus RS, but they are hard to get (paid £130 for the last one!) but I've had my head skimmed and looking at the 2.0mm (.080')Cometic to get the compression ratio well into the area of safe to turbo.
