what are the differences between an evo 7 and evo 9 block?

 

 

Oil feed for the Mivec system needs to be arranged. Evo 7 block needs to have the oil feed taken out to 12mm x 1.25 (i think). Other than that I think they're the same.

 

yes that is correct. only difference is oil port size on back of block. on 4-8 the port is 1/8 BPT and is used for the low oil pressure sender. on eveo 9 the sender is moved to the oil filter bracket. the hole on block is taped for 10mm banjo bolt that feeds the mivec solenoid.