Firstfives.org

Hello.

I'm thinking about slopping in a M30B34 from E28 M535i (218hp, 310nm) in the E12. This has the Motronic fuel injection.

How do I do it/prepare for the job?

Will the in-tank fuel pump from the E28 work in the E12 tank? I will also have to make a fuel return line.

What else is there? Ideas, experiences?


I will also be using a 5-speed transmission from E28, so I will have to make a electronic speed sensor, aswell as changing the speedometer to the E28 type (with E12 front).

You don't really need the intank pump, although depending on the year the assembly might be a drop in. Over here 79-81 cars used the same gas tank as E28s. The main pump mounted under the wheel is the one that really does the work and matters. Mount that one well so it doesn't come loose.

I converted a Bav (E3) from carbs to L-jet many years ago now and only had one hickup, I had a lead from the starter to the ECU on the wrong terminal on the starter so it thought it was in start mode all the time. It's pretty straightforward, especially with fuel be careful and do things right, you don't want any gas leaks. There are a few wires to tie into the car, but for the most part the injection is a seperate harness.