EDIS Ignition Timing - starting from scratch

[SidWell]

I have asked several times and in several ways about how to set up timing from scratch for an EDIS igntion with no luck.

After a long search, I found another forum dedicated to the MS that had the following link. http://powerpage.dk/tuning_ignition_configurator.aspx

 

It is in Danish but the spreadsheet has an English component. If you double click on the spread sheet you can either open it or save it. This may help some of you other guys to get a handle on your spark.

[softopz]

How to set timing on edis from scratch? its laid out clearly in the megamanual

-set engine on 1 compression stroke.

-missing tooth of EDIS triggor wheel must be 6 teeth ahead

-thats your intitial timing and should be very close you should check with a light though.

-set EDIS in limp mode which will give it a 10 degree BTDC (you can simply remove the db37 connector or the PIP wire)

-now get a timing light and see where it lights up set the sensor on #1 plug wire and crank her up remove spark plugs so engine can spin faster but dont forget to ground the spark plug on metal.

- this procedure should light up on 10 degree btdc if not adjust wheel or through your trigger offset in megatune.

- your timing maps can be obtained from the msq sharing thread , which you can fine tune.

[Derek]

I think he's talking about the advance curve.

Derek

[letitsnow]

That spreadsheet is pretty cool, thanks for posting it. Ignition timing doesn't matter much on the ignition system, so this is useful to everybody.

[cygnusx1]

I gave you a good rule of thumb in the last post to get you started, besides, you will never get a perfect timing map without a good dyno and a good tuner. Every engine is different.

[BRAAP]

Cool concept, but not something I'd put stock in for a "good" ign. advance curve, only very rough ballpark!

 

In playing with it a little, the advance curve through the RPM range seems more emission friendly vs performance, i.e. lazy advance curve.

 

Dave summed it up quite well;

...besides, you will never get a perfect timing map without a good dyno and a good tuner. Every engine is different.

[SidWell]

OK...... Then how is it done????? I understand that it is "all in" at 3K rpm. I understand that the idle is somewhere between 10 to 15 degrees.

 

How do I figure out what "all in" is??? Keep advancing the spark until it starts to ping and then back of 2 or 3 degrees?

 

If "all in" at wide open throddle (98 KPa) is 35 degrees at 3K rpm, what should the advance be at partial throddle (75 KPa) and 3K rpm? The manifold pressure does have an effect on the flame front in the cylinder. How much should the spark be retarded for a drop of 15KPa?

 

BRAAP: You say the curve in the spread sheet looks lazy. I see that the advance continues well past 3K rpm. How do you know what a good curve looks like? I am not questioning your knowledge, I am trying to understand the process.

 

Am I missing something? Am I trying to over think the problem?

[cygnusx1]

I found my max timing by listening for ping and blowing up head gaskets. I still don't know what cell I was in when the head gasket blew. I looked at what others were using for a max advance and took an average. Then I subtracted about 5 degrees from that number, programmed it in and slowly advanced the map until it felt faster, better throttle response, and ultimately I blew a head gasket and backed the whole table down again. Now I am inching back up again. What I need is a slap in the face, and an appointment on a dyno that can hold a load point. Idle timing is in your factory manual.

 

I program all non-boosted regions as if it were a counterweighted distributor advance. Simplistic. I only vary advance with RPM, not vacuum. Under boost, I do the same thing except pull timing for every PSI of boost across the board. I have plenty of room for improvement but cannot do much better without the dyno. There is no right answer here. You won't find a hard fast recipe for your exact application.

[SidWell]

I found my max timing by listening for ping and blowing up head gaskets. I still don't know what cell I was in when the head gasket blew. I looked at what others were using for a max advance and took an average. Then I subtracted about 5 degrees from that number, programmed it in and slowly advanced the map until it felt faster, better throttle response, and ultimately I blew a head gasket and backed the whole table down again. Now I am inching back up again. What I need is a slap in the face, and an appointment on a dyno that can hold a load point.

 

I program all non-boosted regions as if it were a counterweighted distributor advance. Simplistic. I only vary advance with RPM, not vacuum. Under boost, I do the same thing except pull timing for every PSI of boost across the board. I have plenty of room for improvement but cannot do much better without the dyno. There is no right answer here. You won't find a hard fast recipe for your exact application.

 

 

Now that is the kind of answer I was looking for. I wanted to make sure everybody else was flying by the seat of their pants as well. Thanks!

 

Does anybody have a copy of the stock advance curve? If I knew the stock advance curve I would use that in a heart beat.

[2fast2Z]

It might be a little late, but if it is needed, i will gladly translate that spread sheet.

Regarding advance curves, attached is a spread sheet i once picked up, somewhere on the internet, can't remember where, could have been here.

 

Chris

Distributor advance curves revision 1.pdf