Electronic replacement for trigger points?? - PeachParts Mercedes-Benz Forum

Graham · #1 09-11-2009, 12:03 AM

After struggling with my trigger points, I wondered if anyone makes a simple replacement for just the trigger points? Something like the Pertronix ignition point replacement.

Seems like it would be a simple enough device - each set of points just stays open for about 1/2 a revolution of the distributor.

GaryF · #2 09-11-2009, 05:38 AM

I've not seen a replacement and not sure the market for it would be big enough. If I was replacing them I'd fit a crank position sensor and a circuit to generate the 4 signals based on that and ditch the stuff in the distributor.

Graham · #3 09-11-2009, 09:46 AM

Quote:

Originally Posted by GaryF

I've not seen a replacement and not sure the market for it would be big enough. If I was replacing them I'd fit a crank position sensor and a circuit to generate the 4 signals based on that and ditch the stuff in the distributor.

It's true the market would be quite small. And each D-Jet car probably has a different requirement.

I think that other than the 6 year or so run on MB,s, they were also used on Jags, Volvos, Porsches , Citroens, VW, Saab and maybe some others. Maybe enough of a market, especially in Europe if a universal fix could be designed.

I was thinking about a split magnet that clamps over the trigger point cams plus a pick up mounted on the cover and then electronics to supply the on-off switching to suit each set of injectors. Probably not much different from a Pertronix Ignitor, except for the electronics providing 4 outputs .

Graham · #4 09-11-2009, 10:19 AM

After doing a search, I found that on V-12 Jags, they DID have an electronic replacement for the trigger points.

Read down a bit on this link:

http://tinyurl.com/n7e7hj

Tony H · #5 09-12-2009, 05:25 PM

If you are going to modify your D-jet system you might consider going with the Megasquirt system and replacing the whole thing. You can keep your injectors and fuel delivery and ditch the trigger points/MPS/ECU.

Graham · #6 09-12-2009, 06:12 PM

Quote:

Originally Posted by Tony H

If you are going to modify your D-jet system you might consider going with the Megasquirt system and replacing the whole thing. You can keep your injectors and fuel delivery and ditch the trigger points/MPS/ECU.

With the high cost and even total lack of supply of some new parts, this may be the only way of keeping the D-Jets on the road for another 37 years.

Other than the Megasquirt, are there any other alternatives?

Carburetor?

Is there a simple Megasquirt replacement? In other words, one that does not require scrounging Throttle switches and other components off other makes of old cars?

I asked about the trigger points, because the Pertronix ignition points replacement is such a simple upgrade. It should be easy enough to design a similar upgrade for the triggers. But, it would still require a good MPS and ECU.

mercmad6.3 · #7 09-13-2009, 04:20 AM

You don't need to go crawling around greasy old cars to get the odd bits for a megasquirt,simply go to online suppliers and buy everything you need new. Nothing worse than hassling with a Megasquirt to find the oxy sensor etc is sick.

Installing carb means making a new intake manifold ( ready to design one that works?) and bear in mind the injection manifold is a DRY mainfold. It is designed for the movement of Air,NOT fuel/air mixture. There is a vast difference in the design of a dry manifold and that of a Wet manifold.
That being said,the installation of Carb takes the engine back to the 1950's.. into the world of chevs and other lesser engines.

Graham · #8 09-13-2009, 09:51 AM

Quote:

Originally Posted by mercmad6.3

You don't need to go crawling around greasy old cars to get the odd bits for a megasquirt,simply go to online suppliers and buy everything you need new. Nothing worse than hassling with a Megasquirt to find the oxy sensor etc is sick.

Starting to think that might be the way to go. Does anyone have a collection of links on Megasquirt so I can start educating myself?

Quote:

Installing carb means making a new intake manifold ( ready to design one that works?) and bear in mind the injection manifold is a DRY mainfold. It is designed for the movement of Air,NOT fuel/air mixture. There is a vast difference in the design of a dry manifold and that of a Wet manifold.
That being said,the installation of Carb takes the engine back to the 1950's.. into the world of chevs and other lesser engines.

You are of course right - I am just getting a bit desperate trying to get 37 year old parts to work properly!

mercmad6.3 · #9 09-13-2009, 05:26 PM

You can't go past their own pages. There are litterally thousands of pages of archived info there. Any question you ever needed answering in fact.
in the meantime there is this.
http://www.hitechengineering.net/DNN/MegaSquirted450slc/tabid/54/Default.aspx

GGR · #10 09-13-2009, 05:44 PM

Graham, I've been reading all your posts with great interest because I have a W111 Coupe currently running with a 3.5 Djet and I also have a BMW 3.0 CSI back in Europe also running with Djet. I also have a nice Citroen DS 23 ie originally Djet that has been converted to carbs that I am planning to return to EFI.

By reading all your posts I am more and more convinced that Megasquirt is the way to go. I already have read quite a lot on it as I am curently working on a euro 5.0 M117 That I want to convert to Megasquirt before putting it in my W111 Coupe. In this regard I got a 4.5 Djet manifold that I have adapted to the 5.0 so that I can reuse most of the Djet stuff already in my car: injectors, fuel rails, fuel pump etc.

Someone here has already converted an r107 Djet to Megasquirt and he has been reusing as much Djet stuff as possible:

finally my 450sl runs on megasquirt

and http://www.mercdjetmegasquirt.britautorepair.com/

I am planning to buy the necessary elements and fit them on my 5.0 in the coming weeks. If you also go that way we could help eachother, and Gurunutkins will also surely support us.

If you do some reading there is some interesting stuff on how best to convert Djet to Megasquirt in the Volvo community.

Graham · #11 09-13-2009, 10:47 PM

Quote:

Originally Posted by GGR

If you do some reading there is some interesting stuff on how best to convert Djet to Megasquirt in the Volvo community.

I have some reading to do! It would be nice to have a support group. Can't imagine taking car with MS into local shop for tune up

Tony H · #12 09-14-2009, 01:12 AM

Here are some links to Megasquirt. I am going to convert my 3.5 111 to Megasquirt and EDIS distributorless ignition when I complete my restoration. I have already aquired the EDIS componets and had a custom trigger wheel fabricated. The Megasquirt system is NOT a plug and play system as you may know but has to be tuned. A lot of the stuff is available on Ebay.

http://www.megamanual.com/ms2/
http://www.msefi.com/index.php

hey_allen · #13 10-08-2009, 07:36 AM

Regarding the original question about replacing the points, and related to the Megasquirt suggestions, have you already found the option of running MS as a spark module alone, with the option of integrating the fuel control later?
I know it's suggested in the MegaManual, but I don't know much about it personally, as I'm going at it the opposite direction, fuel and then maybe spark.

I don't know if I'd mentioned it anywhere on this board, but in my search for a throttle sensor for a MS install, I ended up turning onto the Ford sensors as found on Mustangs and their related engines.

A little creativity to make an adapter and they fit right up on the MB throttle body on my m117 at least.
(A piece of flat aluminum to mount it, and a piece of round stock slotted to fit in the TPS, and slotted on the other end to fit over the throttle shaft in the throttle body.)
Here's a pic, if it helps make the decision any easier.

Come to the dark side, tamper with the stock bits...

Graham · #14 10-08-2009, 11:03 AM

Some time ago, I read an interesting post on another forum that I have not yet followed up on. It said:

Quote:

One way to go is to do a mild conversion to EFI like a Haltech F10-8 and replace the dizzy and get one from a 450 Kjet engine like from 76 and up. All those engines got breakerless ignition. Fits bolt on. But you must change the ignition box from that car also. Then you are problem free from all those issues like triggerpoints and so on. This is absolutely the best way and simplest to get a good EFI conversion with no engine mod what so ever. Just a tip.

(Posted by Supercharger6.9 on Benzworld)

Anyone know anything about the Haltech unit or have any comments on this conversion method?

Gurunutkins · #15 10-08-2009, 08:33 PM

haltech are very nice systems they mostly run batch injection but some run sequential. they have a fairly complex interface but probably allow more parameters to be changed than megasquirt. They can run up to a 32 x 32 VE table. They are very expensive.