I have 430k km on my b230f 740 wagon and I just picked up a b21f that was originally in a 242. I'm wondering how hard the swap is going to be and what else I need. I really love this car and truly want the 4 speed manual that's on the b21f to replace the auto in mine. Would the tranny swap be easier? My motor sounds fine so if the transmission swap is loads easier I might just do that. I have the engine with most accessories on it from the 240, the transmission, drive shaft and ecu

 

thats a M45 4-speed w/o an overdrive? huh.

not sure where you'd find the right length drive shaft for that old 4-speed tranny in a 740, the 240 uses different length drive shafts than the 740 does..

I'm pretty sure manuals use a different final drive ratio than automatics, and the 700 series uses a different rear axle housing than the 200 series.

I would NOT put a b21f in a 740, you need all the horses you can get to move that big body.

what year is the 740? 89+ requires a flywheel with LH2.4 timing notches for the crank position sensor.