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Edis 8 on twin spark V8?

Posted: Mon Dec 06, 2010 2:07 pm
by philt
Hello,

Just wondering if anyone has run a twin spark V8 using Edis 8 module?
I want to run the Merc 113 series motor using Megasquirt and Edis 8 but it has 2 plugs per cylinder
with one coil for each pair.To use Edis I would have to fire two coils together (4 plugs).Is the Edis
capable of this (excessive load)?

Cheers,
Phil.

Re: Edis 8 on twin spark V8?

Posted: Mon Dec 06, 2010 7:23 pm
by a73camaro
I am assuming that you have a 4 cylinder. The EDIS8 will fire 4 times an engine revolution. The EDIS4 will fire 2 times an engine revolution which is what you want.

Re: Edis 8 on twin spark V8?

Posted: Mon Dec 06, 2010 9:50 pm
by Heribert
Hi.
MY MB knowledge drops of fast after M130 around 1972. MB M113 is a bit to modern for me, but anyway. I GUESS thetwo pugs per cylinder are not firing at the same instant but that one fires 5 to 10 crank degrees after the first. If so, you will loose some power if you fire both plugs together.

Best regards

Heribert

Re: Edis 8 on twin spark V8?

Posted: Tue Dec 07, 2010 5:45 am
by Matt Cramer
Most twin spark plug engines I've seen fire them at the same time - although it would be interesting to experiment with staggering the fire by a degree or so. I'd simply use two EDIS modules, sharing the same sensor and SAW signal.

Re: Edis 8 on twin spark V8?

Posted: Thu Dec 09, 2010 1:09 pm
by philt
Hi,

Thanks for the replies - as far as I know the two plugs are fired together.
I think running two Edis 8 modules from the same SAW and crank signals is the best option.

I have used MS previously, about 5-6 years ago I fitted a Rover V8 to a Sierra Cosworth replica.
I am a big fan of the Rover V8 but there are better options out there these days.I like the M113
because it is very light and quite compact for it's displacement (single cam 3valves per cylinder).

Thanks again,
Phil.

Re: Edis 8 on twin spark V8?

Posted: Mon Dec 13, 2010 6:30 am
by molecularbob
Is this the supercharged AMG v8? if yes, then i am fairly sure that the sparks are offset at certain rpm and load conditions, as mentioned here http://www.marcusfitzhugh.com/CLK/engd.html to allow a very lean burn and low emissions.

Looks a very impressive engine, do you know what it weighs with the supercharger fitted?, was looking at the 4.0 lexus, but this has got me thinking.

Re: Edis 8 on twin spark V8?

Posted: Mon Dec 27, 2010 1:39 pm
by philt
Thanks for the link - interesting read.I would be looking at firing both plugs simultaneously, not ideal for lowest emissions but should not be detrimental to power.
I intend using an SL500 engine initially but have also got a 4.3 and an AMG supercharged.I have weighed these, and a number of other candidates and from memory the 4.3l weighed in at just under 180kg, the supercharged just under 200kg.The low weight and compact design make the M113 a good choice for transplants into smaller lighter vehicles.The earlier Merc M119 (5.0l) weighs around 240kg, and from memory the 1uzfe weighs around 220kg.

The Lexus V8 is a fine engine, several sump options and starter motor located in valley but power not the best unless turbo'd / supercharged.I have all the weights and specs in a spreadsheet somewhere, if I can track it down I will post it.The weights quoted were all obtained with the same load cell which had not been calibrated, but a Rover V8 came in at 155-160kg which is about right.

Cheers,
Phil.