Pre FL m20 into FL body

[Gus]

im putting my old pre FL m20 into the new FL body shell

the wiring seems to be a little different (the harness connector in particular)

anything i should think about before i go ahead and connect it all up?

[James Crivellone]

I'm doing the exact opposite, and so far here are the differences I have noticed.

1) C101 Engine/Firewall connector is different (older has less pins) so time to bust out the ETM
2) Waterpumps are different to allow use of older cooling system, so you will want the 88 - 91 325i water pump
3) I beileve the thermostat housing is different as well, so you will want the newer version.

Other then that the motors are the same... I assume you are talking about an 87 M20B25 right?

[mikeedler]

dont know if youve already done it yet, but you should take your orrigional harness and put it on the old motor.