I have been working on an Engine Management System that replaces / upgrades most D-Jetronic components and the ignition system. I am field testing units at the moment for Porsche 914 applications.

This will will solve MPS, injection points, cold start, and throttle switch problems.

The system is all digital and is programmable for performace tuning.

I would like to apply the EMS unit to a D-Jet equiped Mercedes for testing.

Please visit my website shown below for additional details.

__________________
KitCarlson EMS
http://home.mindspring.com/~dave.c/kitcarlson/

hmm interesting, are you replacing the wiring too?

Yes a wiring harness will be developed. The installation will be a snap.

The complete turn-key price will be about $2K assuming two cpu's are used.

__________________
KitCarlson EMS
http://home.mindspring.com/~dave.c/kitcarlson/

Good luck on a noble and perhaps a profitable venture! Yes, I would be intrested in a improved system to replace D-Jet in my 4.5. Your system would have to be inflexably reliable. User friendly, and reversable. It would have to greately improve gas miliage, 15% or better. It would have to improve power, 10% or more. A first class system might be worth 2 grand, the only thing these 4.5's are short on comparied to modern autos are economy and power. Offer a solution for the 4.5 and I may be a buyer, I think others would also.

Tobst:

I'd not get my knickers in a knot about more power -- the D-Jet isn't shaby at all in that department. Better emissions and better milage I would believer (especially milage!), but the D-jet will probably give you more power due to the usually rather rich running it produces.

After all, it IS electronic fuel injection -- it's vastly better than a carburetor, and I don't think a "modern" replacement will do much for increased power.

After all, you are in fact dragging a two ton car around with a 276 ci engine -- they don't do too bad when you think of it that way! This is somewhat smaller than a Ford 302....!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

I have the electronics already designed, I expect to have to develop some additional software and work out the harness.

The EMS unit has the ability to adjust fuel with an O2 sensor. This should help with economy. Optimal control of ignition timing and fuel may increase power slightly. Reliability should improve. The number of electrical connections and electro-mechanical components are greatly reduced. The components used in the EMS design are robust.

I need a test car to get started with the application work.

I welcome leads and suggestions for finding a test car. I live near Nashville, TN.

__________________
KitCarlson EMS
http://home.mindspring.com/~dave.c/kitcarlson/

yeah with a djet you can adjust the map sensor for optimum power, although you'd prolly loose out economy on the low end

mike

Interesting, since I've been meaning to do this for the past 12 years or so, but never seem to find the time. The hardware is trivial in comparison to getting the software right. Maybe this summer. -CTH
PS. Don't forget to deal with the 250E & 280E class engines (the M114E & M110E). I can get you the D-jet schematics for both if you need them. They seem to be the only 6 cylinder versions of the system.

__________________
- cth350@gmail.com
http://www.111lakeside.com/

OK Peter, so what would you suggest I do to get some more power out of this machine. Would cams and heads from a 3.5 give me more HP without harming engine? I was hopeing you would address this question?

Tobst:

0.8 hp per cubic inch on a 30+ year old engine is pretty spiff. To get more you are going to have to do engine modifications. Should be able to push at least 320 hp out of it, but it won't by by doing small twiddles.

You should first verify that your ignition and fuel systems are working properly and that the cams are in good shape -- 0-60 in 9.5 sec, top speed of 125+ mph is more that adequate for me, and if you don't get those results, the engine is still sick!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

These old engines with D-Jet could not be accused of lacking power for their size (except perhaps for some of the de-toxed versions you got in the USA). Here in Australia, my '73 350SLC which has a high compression Euro spec 3.5 M116 is not too shabby at a conservatively rated 200hp DIN (230hp gross SAE). I remember as a teenager my father had a '72 280SE-3.5 sedan with the same engine. We derived great enjoyment from blowing away local carby fed Ford 302 and 351 or GM Holden 253 and 308 V8s in traffic light drags. All this from a D-Jet fed V8 of only about 216 cubic inches hauling a much heavier car than those Fords or Holdens.

Regarding MB 250CE, 280E and 280CE sixes with D-Jet, from memory these had an intersting arrangement where two outputs of the D-Jet each fed a pair of injectors whereas the remaining two outputs each fed only one injector. In this way four outputs were used for six injectors. On the V8s injectors were all run in pairs meaning four outputs for eight injectors.

A replacement for the D-Jet sounds interesting. From my experience and observations most problems are with the ancillories (eg. manifold pressure sensor, trigger points and of course fuel leaks). I am amazed at the reliability of the D-Jet ECU considering the technology used (including some germanium transistors). In the 21 years I have owned my 350SLC I have had the ECU out once after dropping two cylinders. I diagnosed this as a faulty transistor (driver for the output transistor for one pair of injectors). Admittedly in the 107 series it is in the less hostile environment behind the dash whereas earlier cars had it in the engine bay.

__________________
107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

Peter, don't get me wrong. My Car is in really good shape the engine is strong and I have had it to 115, 60 to 90 is swift and sure it will hit 0-60 in 9 sec. or so. Orginal 57,500 or so miles and runs like it. That being said I want 30 or so more horses, just looking for the best way to do it. Not much on the after market for this engine. I not looking for much, just the best method.

Greg,

I agree the D-jet as I know it was a good system. The main problem is the 30 plus years wear on the mechanical components as you suggest. The tunability of the D-Jet is quite complex, it happens partly in the MPS and the rest in the analog ECU and temperature sensors. Aging of components and sensors, leads to difficult problem solving of the injection system.

The EMS system uses a similar speed-density system based on more robust modern components. An example: the pressure sensor is a component of the circuit board. It is a linear, temperature compensated, solid-state pressure transducer.

The ability to view sensor values with the EMS communications interface helps insure proper operation and calibration.

The EMS has the ability to be tuned for engine modifications, cam, displacement changes, exhaust, and even turbo.

__________________
KitCarlson EMS
http://home.mindspring.com/~dave.c/kitcarlson/

i'm taking mine to the dyno next week, ive got 3 runs so i was gonna play with the mixture. 1 run at the factory setting (my mps is untouched), 1 run 1/2* turn richer 1 run 1/2 turn leaner.

at the very least we can get some tuning info for kit

mike
* i wanna try it on the street first, i want to make sure its not too much or too little

Here's your candidate car. For 71, it's a 3.5 or 6.9. If it's a 6.9, then trade the parts for a 3.5. If it's a 3.5, you're golden. I can hand you a credible 4.5 motor if you want to collect it from NY. -CTH

__________________
- cth350@gmail.com
http://www.111lakeside.com/