puttin an m20b25 in my eta

[Bav///Motorworks]

no help on bimmer forums but i picked up a motor and tranny, going to swap it in, i have a few questions about the swap. wut can i do about the guage cluster? can i just swap in the I's cluster without a problem? and also how would the car run with the 2.93lsd. i will be gettin the 3.73 or 4.10 down the road but for now i'll be using the 2.93. so i was wondering how it will run till than thx

[Van Westervelt]

Wont pull as hard with the 2.93, but you will get great gas mileage! :) And then the opposite if you go with a 4.10.

The clusters, are pretty swappable from what I understand, so long as youi do the whole cluster. You cant pull a tach out of a motometer cluster and put it into a VDO cluster.

If you need to do any rewiring now is the time, you dont want to pull the cluster out too much.

Anything else?

[ryan_george]

I put an '87 "i" engine into my '86 325e last year, and it went pretty smooth, but I will tell you the BIG issue I had.
I swapped the entire cluster from the "i", but put my original speedo/odometer in so my mileage was the same. As far as engine wiring, there was nothing to do at all. Since the "i" ECUs have a built in diagnostic system, along with a Check Engine Light, you'll need to wire that light up manually. It's not necessary, but it is helpful if you are having running problems. You tap into the big circular connector (C101) by the fusebox, and run a light from there. I forget the exact pin number you use, but I'm sure you can research that. If you get stuck PM me and I'll dig it up.
I ran my 2.93 for about a week, and you won't have any issues with it. It'll just be a bit sluggish, but you'll still go.

Here was my BIG problem that had me stranded for a while. I installed the 13 button OBC from the "i" at the same time. However, these OBCs have the CODE feature which will not let your engine start. I must have missed something during the install of that, because the OBC was locking out my engine. It was assuming I was stealing it. All that was done to fix it was bridge a wire (again, I don't remember, but I can find out if you run into this problem).
Other than that it's pretty much a plug-and-play. Good luck, and have fun with it!

[Van Westervelt]

It was assuming I was stealing it. All that was done to fix it was bridge a wire (again, I don't remember, but I can find out if you run into this problem).
Other than that it's pretty much a plug-and-play. Good luck, and have fun with it!

Bidge what wires?!

[ryan_george]

Bidge what wires?!

Part of the OBC wiring runs through the firewall at the driver's footwell. It goes to the temp sensor and horns, and I must have missed something when I wired mine up. There's a wire in that section that needs bridging (at least in my case).