Got a 2.1 stroker going in soon, with Spec C AVCS heads, I plan to run a naughty amount of boost through a SC46.

Any recommendations guys, I was guessing Cosworth MLS but unsure on thicknesses.

 

There's no correct thickness with built engines. It's calculated when you have all the parts built up. It depends what pistons you're using, how much the decks and heads have been skimmed and what static compression ratio you're aiming for.

Best to get the decks skimmed, heads skimmed, converted to 14mm stud kit to hold all that boost in. You could even use rings in grooves instead of head gaskets for the best in sealing

 

As above, depends on your compression ratio and valve train / cams which is related to turbo choice and characteristics your after, I'm no expert but it's best you talk to one and decide on a compression ratio that's best suited to your intended use and work backwards from there.

Did I hear you say mostly drag strip in another post?

This is really something you should plan from the beginning of your build along with pistons, rods and valve train to match, A bit of planning at the start means you end up with an engine that performs very well at it's intended use, as opposed to just bolting a bunch of quality parts together and hoping for the best.

I'd have your heads checked properly too, especially if you plan on running high boost as they tend to have cracks around the plugs that are not visible to the naked eye, which will restrict the amount of boost, like the set of JDM heads I bought recently, looked perfectly good until cleaned and some freezing type spray put on them, then the cracks appeared as if by magic on all but one of the four plug holes.