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rsrmike rsrmike is offline
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Join Date: Jan 2008
Location: Birmingham, AL
Posts: 538
First of all, unless your going to get fairly radical and spend serious money tuning to maximize the benefits of twin plug, it may not be worth it in your case. Considering the difficulty involved.

That being said, here is one way you could do it:

Obtain and mount a second ignition control module and coil.

You should be able to split the signal from the crank sensor with a fabricated "Y" harness.

You would need to find a way to mount a separate air temp sensor as I don't think you can "split" that signal. It needs to read the same air temp as the other so the timing won't alter from different temp sensor inputs.

You can then mount another coil and obtain a twinplug distributor but that will open another can of worms.

There may be some difficulting fitting all that as you know. It can be done but would require extensive, expensive fabrication IMO.

You can also split the MAP sensor hose w/ a T for each control unit.

I've never done this but I don't see why it wouldn't work.

A better aproach would be to split the signal from a single contol unit and fire two coils but I don't know how to do that. I think the 965 may be a newer mercedes sourced CD ignition?

Andial makes a splitter that works well for a 964 dizzy in a 3.2 motronic setup.
I have used one of these and they work, I don't think it works with your ignition though.

And finally, you could use an Electromotive XDI2 twin plug setup. You would need to remove your crank pulley and send it to Richard Clewett. He can machine the 60-2 teeth into your pulley that will align with his sensor mount.

But then you are switching to a wasted spark setup that is not a good as your CD ignition in many peoples opinions.

You would also need to leave your existing crank trigger and ignition control unit in place to operate some of the CIS control units, mainly the fuel pump relay trigger, overboost protection, etc. All that relies on the factory rpm signal and they are not the same from electromotive to 965.

In the end, I say spend your money on bolt ons for the engine and CIS tuning. If you run out of stuff to do in that department then you've likely spent enough money to where a nice MOTEC setup w/ coil on plug would look cheap.

Just my opinion, but FWIW, I have a 965 ignition module I would love to sell but I think you would be wasting your time.

Good luck w/ the brainstorming-no harm in thinking...
Professional Overcomplicator

Last edited by rsrmike; 09-02-2008 at 08:43 PM..
Old 09-02-2008, 08:34 PM
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