PeachParts Mercedes-Benz Forum - View Single Post

duxthe1 · #3 09-19-2010, 07:30 PM

I've been looking into this as well. The 103 isn't the easiest engine to adapt. From what I understand you can't use the stock flywheel for a trigger signal. Most adapt a ford 36-1 wheel onto the front pulleys for the trigger. That's not the easiest task either. I'm looking at fabricating a system that will be driven by the cam. The 36-1 wheel I have fits perfectly into the timing cover instead of the distributor. I'm thinking to turn it into a (2X)18-1 by removing another tooth 180 degrees which will be enough to time a 6 cyl engine from the cam. I have a line on what I believe is a 60-2 flywheel that will interchange but that is a huge undertaking on the 4-M and I will have to be fully committed before replacing the flywheel.

The fuel system is another consideration. The intake doesn't just lend itself to fitting EFI nozzles. I've fabricated some custom parts to mount, locate, and seal the injector. In stock form the 103 delivers idle air to each cylinder through the nozzle holder, an important consideration when making custom parts. I'll have to take a few pics of my parts when I can find the camera. (ie where did she put it?) I have no experience with this yet but I expect the stock fuel pumps to work fine. I plan to use a modified 104 rail and pressure regulator like mentioned above.

Yet other consideration is the tps. The 103 doesn't have a true tps. It's simply idle and full load contacts. You'll have to find and adapt a tps to the throttle body. FWIW, I have a spare intake manifold on the bench for trial fitting and experimenting, something I'd recommend you do as well if you have the means. My intention is to have a complete setup trial fitted on the spare intake. That way I can just swap over the parts quick and easy with no surprises.

EDIT: In picture two it shows the o-ring that seals the injector to the intake. It sandwiches between the nozzle holder and the injector body. The groove with holes is for idle air distribution. Not seen in the photos the holder has a 60 degree bevel between the injector and the tip of the nozzle holder.