TecknoMike

iTrader: (1)

Hi guys,

I'm always trying to search and search before I post, but I can't find a 100% answer. I'm in the process of building a 408 and will be using 799 heads. I have seen people say that the LS2/6.0L head gasket is 4.039" bore diameter, but Summit, Jegs, and even TSP all show that the 6.0 head gasket (GM 12589227) is 4.020" bore diameter.
So, what gives?
Will using the LS3 head gasket (GM 12610046) be an acceptable head gasket to use without losing too much compression?

Thanks!

JakeFusion

iTrader: (7)

Use the LS3 gasket. It won't hurt compression. You may go from say 11.5:1 to 11.4:1 using it.

LS9 is also an option. It's more expensive but it's the best GM gasket you can buy.

KCS

iTrader: (20)

The 6.0L gaskets are about 4.050" and the 6.2L are closer to 4.100". I just had calipers on both sets of gaskets maybe 4 weeks ago.

TecknoMike

iTrader: (1)

Well shoot, I had already returned the 6.0 gaskets I bought a few weeks ago. I think it's weird that all these vendors are all saying the exact same measurement when it's being found to be entirely different.

I think I may go for the LS9 gasket then, if not the LS3.

I assume the LS9 gasket is the best of the two since the LS9 gasket has to handle boost from the factory.

Thanks guys!