Discussion and questions related to the course Practical Engine Building
I am working on building a 2JZGE VVTi engine. I will be using a built bottom end with 8.5 CR pistons, however the head will be the GE VVti piece. My goal for the engine is a 1000 hp build. Ideally I would like a CR of 9:1 or thereabouts. If I keep the standard GE single layer headgasket, it will give me a CR of 9:1.
My dilemma is whether I can use the single layer headgasket for a high horsepower build or do I need to go for a MLS head gasket. If I go for an MLS gasket, I will need to deck the head to achieve the desired CR.
You said "or thereabouts" - that implies you aren't dead set on that and the very small potential difference in CR is going to make very little difference. If you haven't done so, a fine cut to true the head is generally a good idea - if you haven't done so, you can ensure the surface finish matches whatever head gasket you decide to go for - some can be fussier than others.
CR 9:0 on 1000 hp build will require very high octane fuel. If that is the case than you can get away with thin steel gasket from 2jz NA. If high octane ( or e85 or water injection) is not an option, than i would advise to lower CR down to 8.5-8.6 with multilayer gasket.