rusefi.com

Hey, I'm David. I'm based out of Sarasota Florida. I've got a few projects, but we'll start with this one. I have an auto 1991 BMW 850i that I'm swapping to a later M73 V12, from the M70 originally, and swapping it from a 6 speed manual from a 4 speed auto.

Will probably use the engine from vin DH66418, which is a '95 E38 750il, using two DMEs with the Bosch 88 pin connector. Hopefully we can get that going. Here's an example of some of the same DMEs. Here are the two cars I'm going to be working on getting this stuff going in, but E31 first! And I've got some equal length headers I'm gonna be making here shortly as well just for shits and giggles. I'll update on everything I'm trying to do, but for now, just to make a small list of some weird to-do bits I'm currently doing...

• Do the same thing Bill's doing with the 420G to mate it to the M73
• Figure out the Nissan (VQ I think) throttles that I'll be using
• Find a way to make a Toyota/Nissan pedal sensor fit in the car

Those are some cool projects, happy to help with the ECU side of things here.

If you are interested to keep original 88 ecu plugs I can include https://www.ebay.com/itm/88-pin-ECU-Connector-BWM-for-custom-harness-M50/333752255007 instead of 134 pin headers with your harness. I also have a breakout board for that connector - actually waiting for second revision to show up from the factory.

https://github.com/rusefi/rusefi/wiki/HOWTO-M73-v12-on-Proteus is focused on 134 pin connectors but it should be the same idea with older harness. Do you have nice wiring diagrams for 1995 750?

Yeah, like on the phone I would prefer just to keep the 88 pins. I can try to find some diagrams. I used to have them, I'll just have to do some searching.

They should be damn near the same.

this 1996 diagram could be useful maybe https://github.com/rusefi/rusefi/wiki/BMW-e38-1996-750

On mobile right now, so I'll have to revise a bit later, but I've just moments ago finished up my modifications for the 420G transmission I'll be using on the M73.
Bill is also doing this modification, and his thread currently has better pictures of the process.

I'll add my own step-by-step here shortly with a mix of Bill's own instructions since my own ideas were pretty much the same as Bill's.

Any updates on this?

Im just starting researching on this and everybody uses the later M73TU harness

My E31 is a early M73 with the 88 pin like yours