E30 Zone

I know this has been beat to death but ive read every post on this topic and still havnt come to a conclusive answer.

Planning a m20 3.0 stroker using a m54b30 crank (89.6mm), 135mm rods from a either a 325i (I think they are 135mm) or a set from the m54 engine 135mm, and finally the M20B25 9.7:1 pistons, and an 885 head. Completly refreshing the entire engine and making sure all clearances work, seen that rods can hid the block or the pistons can hit the crankshaft...

Here: http://www.e30zone.net/e30zonewiki/inde ... roker_Info

Says that i can use the original 2.5i pistons with the 89.6 crankshaft but not what rods to use... Would I need to use the entire rotating assembly from the 330i or could i mix and match the parts together that i listed before?

Thanks.

nobody really does it using m20b25 pistons even though its possible to make it fit using 130mm rods if you tried hard enough, its a lot of machining work and ive yet to actually see someone try as there are better ways. ive seen someone do it with 85.8mm stroke though

most use custom pistons or machine down other pistons from 24V engines (or even find some that can be used straight out of the box) to get the right piston compression height. using the correct custom pistons is the best way as you can preserve the OE dome and not have stupid 4V valve reliefs in the top but its about $1000USD for a set of custom slugs

Thanks for the reply,

Im trying to stay within a certain budget and not spend money that I dont need too, I have decided to do a 2.8 stroker instead because from my understanding and reading what other people have done, there is alot less machine work involved in the 2.8 crank.

I want to retain the original 2.5i pistons and not order custom pistons to keep cost down and still retain something in the rotating assembly from the M20. I think the best option for me is 2.5i pistons, m52b28 crank, and 130mm rods, Then working around it.

yes that is a proven solution