E34 M30 or M50 swap?

[goodfolk1]

I have a 1990 525i 5spd manual. I need a motor and I have found two cars that I can get the motor from. One is a 1989 535i(M30)automatic and the other is a 1991 525i(M50) automatic. Which of these is the easier/ better/ cheaper swap to do. I have a tranny from a 1993 325i cabriolet(M20 motor). Will it work w/ one of these motors. Will my drive shaft work?

[jfj707]

I don't believe any of those are really "easy" or cost-effective. I'm sure the others will have more helpful details.

I see M20 engines go for $300-400 around here.

[nmp411]

I'm pretty sure the M30 would be an easier swap, but you would need a new trans as well.

[goodfolk1]

which tranny will I need?

[strad]

For an M30b35 you need a Getrag 260/6 (as opposed to the 260/5 which is what a five-speed M20 car would have). There might also be other M30 transmissions that will work -- I only know what would be installed in a manual E34.

An M20 trans will bolt up to an M5x engine, but be aware that the shift pattern will be canted 10 degrees off to one side.