can someone help me i need to know wheather a average sierra 205 block is the same as a cosworth 205 block? i will have it bored 1mm over size to use my pistons. so the bore size does'nt matter cos i will get it rebored.
but are there any other differences and can i use it? please help

 

(cosworth 205 ones) were picked from the better grades of the metal casings I believe! other than that their the same

 

cheers mate lovely thought that was it