Is it totally standard now?

How much is big bhp? How deep are your pockets? Are you converting to rwd?

From what I've read the BW EFR turbo range are the way you want to go, maybe a 7670 external gate on a linered block/CP pistons/arrow long rods and arrow crank. Send the head to Neil Roper.
I think id be asking also what do you want to use it for?

Best advice is to speak to the guys that have built a few.