Hi I have 2 x 3.5 litre engines - one and M90 with the 93.4 bore from 1980 the other an M30 from 1988 with the 92mm bore and longer stroke. the M90 needs new bearings and a general overhaul whereas the M30 is in better condition
the M30 has larger inlet valves and wider ports and has benefitted from a little port work and is in better condition plus double valve springs
What are the best options for me with these 2 units - is it a straight forward excercise to swap the longer crank into the M90 and create a 3.7 - would I need special pistons.
Or could I simply bolt the M30 head with the port work onto the M90 block and retain the higher compression or would I need to skim the head - I am sure it has been covered here before but I could not find the thread.
thanks in anticipation
the M30 has larger inlet valves and wider ports and has benefitted from a little port work and is in better condition plus double valve springs
What are the best options for me with these 2 units - is it a straight forward excercise to swap the longer crank into the M90 and create a 3.7 - would I need special pistons.
Or could I simply bolt the M30 head with the port work onto the M90 block and retain the higher compression or would I need to skim the head - I am sure it has been covered here before but I could not find the thread.
thanks in anticipation