MANUAL SWAP HELP

[RattyTatat]

84 528e M20B27 Auto Tranny gone. Looking to do a Manual swap. I know I need a Getrag 260 but can someone help me with what I can get that from ? I believe that the way I understand, a M30 tranny wont work. If the tranny is from a M20B25, will that work ? I want the car to stay as original as I can, and I know a lot of work to replace but I think I can do it, I just dont know where to start. Am I serching for a 260 from a M20B27 only ? Thanks

[Mike W.]

You are correct that a M30 tranny will not work, the bellhousing is different and it will not even come close to bolting up. I would think one out of a M20 powered E30 or even E34 would work, but neither Realoem or Car-Part are showing it as interchangeable. I don't know why, ratios? Different output flange? Different mounting? No idea, but I bet they would work. I've even heard of guys putting later trannys from M5X cars behind M20 engines, so I would think from a different M20 would work. Don't try the M5x trannys though, the engine sits at a different angle. You will need lots of other bits and pieces, but https://car-part.com/ does show a bunch of trannys available for moderate cost.

[RattyTatat]

Thank you Mike. This is a start.

[Galahad]

You are correct that a M30 tranny will not work, the bellhousing is different and it will not even come close to bolting up. I would think one out of a M20 powered E30 or even E34 would work, but neither Realoem or Car-Part are showing it as interchangeable. I don't know why, ratios? Different output flange? Different mounting? No idea, but I bet they would work. I've even heard of guys putting later trannys from M5X cars behind M20 engines, so I would think from a different M20 would work. Don't try the M5x trannys though, the engine sits at a different angle. You will need lots of other bits and pieces, but https://car-part.com/ does show a bunch of trannys available for moderate cost.

The M1.3 cars (E34) aren't going to have the speed and reference sensor holes cut IIRC

[Mike W.]

The M1.3 cars (E34) aren't going to have the speed and reference sensor holes cut IIRC

Good point, I didn't think about that. They might not even have the bosses, but I would think early E30 325i would at least have them, but maybe not drilled as there was a year or so overlap.