Hey guys just a couple questions with rebuilding my rb30. im hoping to use my a6 engine, and re-do the whole thing with some recently bought some 040 oversized CP Forged pistons and forged rods, a wade 818 cam, polished heads, gt35/40, forward facing plenum. am looking for roughly 300kw but still hope to use it around the streets a bit. my question is (from what you can see with the picture) are these pistons made for an rb25 head? and will they still fit an rb30 head if they are? or do i have to either sell these pistons and buy ones to suit an rb30 head or either change to an rb25 head and change my intake? Some original photos have not been recovered yet.

they look like rb30 they look to have a dish in them

They are to suit rb30 head mate they are my old pistons all rb30 pistons have cut outs to suit 4 valves hope that helps ---------- Post added 28-10-11 at 16:44 ---------- O and the comp ratio is 8.2.1 on those pistons will handle 300 easy with this piston rod combo

30thou oversize. hmmm. Wouldn't that be running close to the water jackets. Some original photos have not been recovered yet.

acutally they're 40 thou over and no not really you can go up to 60 thou but your best getting your block sonic tested to make sure its all good and theres enough meat in the walls to make it reliable

Quote: Originally Posted by madrex [View Post] They are to suit rb30 head mate they are my old pistons all rb30 pistons have cut outs to suit 4 valves hope that helps ---------- Post added 28-10-11 at 16:44 ---------- O and the comp ratio is 8.2.1 on those pistons will handle 300 easy with this piston rod combo oh great thanks heaps mate. just wasnt sure as the rb30 head has the 2 valves and the 25 head has 4 and this had the cut outs. thanks heaps for the help guys

No worrys mate