Originally Posted by Spazdoc
A question I have is how is the current 335/N54 engine related to the 328 and the older 330 engine? Is the 335 simple a tuned, turbocharged version of the others, or a completely new engine altogether?
Just about everything about the N54 is different from the N52 used in the 328 and 2006 325 and 330 including the block construction (aluminum with cast iron liners vs aluminum/magnesium).
Whether it's completely new or not is sure to cause an argument. Many components ARE new but the block is the same type of construction and bore/stroke dimensions as the E46 engine.