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post #36 of (permalink) Old 05-23-2019, 03:51 AM Thread Starter
TZ_280SEL
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Date registered: Feb 2010
Vehicle: 1972 280SEL daily driver. 904 Dark Blue with cognac interior. euro 4.5 engine
Location: Williamsburg, VA
Posts: 390
Mentioned: 3 Post(s)
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For fuel, I kept the stock D-Jet pump and filter at the tank but the rest is new. I used EV1 19# injectors. I purchased a length of fuel rail billet (DASH-6) from Ross Machine Racing and drilled the bores for the EV1 o-rings. I tapped the ends of the fuel rail with an NPT tap and used simple NPT to barb hose fittings to run my fuel line. I used a generic inexpensive vacuum compensated pressure regulator which is set at 45# with no vacuum. There is a vacuum connection at the rear of the intake lower plenum which I used for the vacuum signal for both the fuel regulator and the MS MAP sensor. The tank return from the regulator is original. I did not keep the fuel damper.

I used to chase fuel leaks on my D-Jet regularly. I have not, knock on wood, had a leak since the conversion to MS. I am only running a 36-1 crank sensor so I am using semisequential injection.

For ignition, I decided to eliminate the distributor. I know you can keep it, but I wanted control of advance and I wanted to eliminate the issues with rotor cap wear and the resistor/non resistor plug/wire issues we all seem to chase. I removed the distributor completely and machined a round blank with an o-ring groove in it the same diameter as the distributor base. I then welded that to a small plate with a hole that lines up with the distributor hold down bolt location.

I added a 36-1 wheel to the crank pulley (you have to grind off and reattach the balance weights if yours has them). I purchased the wheel from a guy on ebay in Belarus. I used a Honeywell 1GT101DC hall effect sensor for the trigger signal. I made a mount for mine which attaches to the front of the engine. It replaces the existing plate which covers the distributor timing gear. I don't have any good pictures here but will take some this weekend and post for you.

For ignition, I chose to use LS2 coils and do coil-near-plug with wasted spark. I purchased a set of used LS2 coils complete with bracket and harness. I reused the harness but made my own bracket. It is probably hard to see in photos, but my fuel rail is held in place by two brackets which bolt to holes in the head for the original injector hold downs. The billet fuel rail has plenty of meat at the bottom to drill through without hitting the bore which carries the fuel. For my coils supports, my bracket also attaches to the fuel rail in two places and I tapped the two "holes" in the valve cover originally used for the plug wire guide. For plug wires, I used MSD wires from a "build your own" kit and purchased MSD 45 degree LS2 connectors for the other end. (I made my own because stock LS2 coil wires are about 3" too short) I am also running plugs for an LS engine. The threads are the same even though the socket size is smaller.
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