all pistons will fit your block (providing you get the correct size i.e. standard bore +0.5 etc). But in order to acheive the correct comp ratio they will need machining before you put them in your block.

as for the cosworth pistons, i mean that you may be able to get a set straight off the shelf that has already been machined.

whereas with the mahles. you usually just purchase a standard set of 4x4 jobbies, then take them to the machine shop for the work.


hope this helps

paul