deadchef
xsbobblehead
laid the head gasket down to check the fit and noticed about 1.5mm short around the back edge and along the right side. also noticed poorly aligned holes for oil passageways. should this be a concern? is there a better option?
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What about the alignment of the crush ring to the cylinder?
deadchef
xsbobblehead
the crush ring and cylinder look to be concentric of each other.
deadchef
xsbobblehead
so i just wasn't completely happy with the athena head gasket so i figured i'd pony up and buy a vesrah head gasket. test fitted and it sits even worse! i drew a little dry erase black marker on top of the cylinder to help show in the pics how each gasket looks.
athena gasket
vesrah gasket
it's difficult to see in this pic but the metal ring on the vesrah gasket actually lays over the edge into the cylinder.
i think the athena gasket will be fine but i don't think the vesrah gasket is even acceptable to use. i'm at a second overbore and mmm says that a stock size gasket will work up to 4 over. should i consider a big bore gasket?
athena gasket
vesrah gasket
it's difficult to see in this pic but the metal ring on the vesrah gasket actually lays over the edge into the cylinder.
i think the athena gasket will be fine but i don't think the vesrah gasket is even acceptable to use. i'm at a second overbore and mmm says that a stock size gasket will work up to 4 over. should i consider a big bore gasket?
Unfocused
I Love Boobies
Like has been said. The outside alignment isn't a concern. It's the inner part that is the main sealing point.
FB71
Expert Turd Polisher
I would not use the Vserah gasket. The fire ring misalignment is unacceptable. The Athena gasket actually looks very good. Its perfectly normal for the gasket to not reach the outside edge, it doesn't need to. The fire ring should be slightly larger in diameter than the bore; when the gasket is compressed during torquing, the ring will crush some and spread. Since the gasket is securing the ring on its outside diameter, the ring will expend slightly toward the center of the bore, reducing the gap. The fire ring should never extend into the bore (hopefully obviously), and should stay a bit recessed from the bore. This provides a 'quench zone' (an area where fuel and air don't mix well, and subsequently don't burn). Quench zones increase tailpipe emissions, but control combustion chamber temp, reducing detonation and thermal fatigue. In this case, specifically the fire ring of the head gasket. The cooler it can stay, the longer it will last.
deadchef
xsbobblehead
good to know. thanks!
