I'm going to be building up a cosworth engine and i know that certain aspects of each engine (2wd and 4wd) are superior.

I know that the 4wd block is stronger, but am i right in saying that the turbo and head are also better? and that the 2wd exhaust manifold is better?

Thanks a lot

oh, also are the 2 looms the same? and which ecu do i want?