RB26, Which headgasket should I get?

[boostedh23a1]

I hear good things about the apexi one. I am probably going to run N1 turbos or a small to mid size single borg warner EFR. What size should I look at? 550whp S30 so nothing crazy hp wise.

[Carl H]

stock with arp studs...
i've pushed 26psi thru my 30 using a stock 26 composite hg and arp bolts (25, not 26).
holds fine under daily driving (14psi) and high boost pulls (22).

just make sure the head and the block are true and you'll be just fine.

[boostedh23a1]

Why the rb25 bolts?

[Carl H]

rb30 block, same bolt size as the rb25/20...if i swap to a 26 head i'll tap the block out.

[Shocker]

rb30 block, same bolt size as the rb25/20...if i swap to a 26 head i'll tap the block out.

Wasted effort IMO, many very high HP 30's using rb25 arp 11mm studs with no issues. Including Robs 1500 hp+ FED... I was thinking of doing the same thing until I researched how many people kept the 11mm with the 26 head and are making big #'s.

As for a gasket I've had good luck with the Cosworth unit. XS Engineering (not power..) did a little review on it and compared the "squish area" of the gasket to other brands and OEM. It sealed very nicely and is also reasonably priced.

[Carl H]

agreed.
we stuffed normal 25 studs into my buddies 30/26 combo and its doing well.