Which other M30 models fit in my e34 535i?

[chesster6969]

Im in need of a lower mileage M30B35 engine for a 1990 535i 5 speed.
I thought that any 88 and up E32 M30 would work but I've had conflicting reports about that.
Anyone know what BMW models i could use an M30 donor?
Or have a list/idea what would be needed to make other model M30's work in an E34 535i

Im in the SOcal Area if anyone has a lead on a E34 compatible M30 shoot me a PM or EMAIL

ANY info greatly appreciated!!!

[Kalevera]

Any E32 or E34 M30, the late M30, will fit. Swap your current engine harness over to avoid any EML incompatibilities.

Theoretically, I guess you could also get an E28 or E24 motor. Not worth the necessary modifications to get it installed unless it's an S38B35, though.

EDIT: what's wrong with the current engine, anyway?

best, whit

[chesster6969]

present engine had engine failure from overheating+dumb PO.

Interior/exterior very good otherwise

[Kalevera]

So why did it overheat? Bad head gasket? Cracked head? Cracked block?

Depending on the situation, it might be easier to repair what's wrong with the existing engine versus replacing it entirely. It takes a lot of abuse to kill an M30 bottom end. If the head is warped, Leo or Dave at memphis can bend it back to spec.

best, whit

[Karl]

I'll second that--bottom end of the M30 is pretty well bulletproof. Usual heat problem is warped/cracked head, which can be replaced or rebuilt. And if you rebuild it yourself you know what you have, unlike an engine from a wrecker.

But back to your original question--virtually any M30 engine can swap in, but running improvements (like better oil pump) as time went on means the later engines are preferable. I put a '91 735i engine into my old e12 car. Basically set the two engines next to each other and swapped anything different from my old engine onto the new one. Even off the wall stuff like oil pump pickup and heater hose nipple just unbolted off the old engine and bolted onto the new one.

[Kalevera]

Haha, I was thinking of writing the same thing about any M30 "working" -- but there's no benefit for using an E12/E23/E24/E28 M30 over the late motor.

By the way, how'd you work out the motor mounts on your E12 conversion? We designed a set of motor mounts to fit the S38B38 (therefore late M30/S38B36) into the E28/E24, as the mid M30s are missing a few bolt holes. Don't know the differences between the E12 subframe and the later cars as I've worked on about three of them, but I'd be interested to hear.

best, whit

[chesster6969]

Mechanic said engine has seized. Also head is warped but I dont know what percentage its off from straight.

Was the motronic versions the same between 88 up E32 735i/il and E34 89 up? Or from any other

I want to get the car up and running first off. So I wouldnt be inclined to rebuild the present engine right now, maybe down the line