EDIS Timing Question

[Bravin Neff]

I converted my V8 Mustang to EDIS, and mostly everything appears fine except my base timing is off. EDIS-8 is supposed to default to 10 degrees BTDC when no SAW signal is present, but my timing light showed it to be at 5 deg BTDC.

Thinking myabe my pointer or timing-marks were off, I verified they are in fact exactly inline at TDC using a timing wheel and piston stop.

The standard setup for EDIS-8 is *supposed* to be such that when the crank is at TDC, the VR sensor will be inline with the middle of the 5th tooth (going c-clockwise from the missing one). That's how I set mine up initially, but when I went to verify timing with the light (using the engine starter to crank), I saw 5 degree BTDC initial timing, as I have said. To correct this, I loosened up my 36-1 trigger wheel and rotated it further c-clockwise, so now the sensor is *exactly in between* the 5th and 6th tooth. This is how I "corrected" the system to now show 10 degrees BTDC with the timing light. But this solution can't be right.

Any ideas what's going on?

Regards,
Bravin Neff

[Matt Cramer]

Your solution sounds right to me - it works, doesn't it?

[Bravin Neff]

LOL I guess you have point!

It just doesn't feel right. I mean, in order to "solve" the problem, I forced my trigger wheel and VR sensor relationship to be out of conformity with EDIS literature. Have you ever heard or seen such?

Regards,
Bravin Neff

[trakkies]

What sort of timing light are you using? Some don't like wasted spark.

[Heribert]

I think your initial install was correct

If you hook upp EDIS on a test bench that can start at low rpms ( I did) you will notice that the EDIS in standalone ( ie no SAW) will start att almost TDC and as rpms go up towards 400 the ignition point will approach 10 BTDC.

So , install it as per the book and once your engine idles in standalone at 600 + rpm you will have a rock steady 10 BTDC ignition point

The "retard " at cranking will ease starting a bit, and yes, I believe the Ford guys made this intentionally to aid starting.

Best regards

Klotzakk

[Bravin Neff]

by trakkies » Mon Jul 18, 2011 11:13 am

What sort of timing light are you using? Some don't like wasted spark.

It's an old school Craftsman. I have heard about fancier timing lights that don't like wasted spark. How would I know if that applies to mine? For what its worth, mine has no adjustability or settings whatever. It is just an induction based light and nothing else. Does that mean anything?

[Bravin Neff]

I think your initial install was correct

If you hook upp EDIS on a test bench that can start at low rpms ( I did) you will notice that the EDIS in standalone ( ie no SAW) will start att almost TDC and as rpms go up towards 400 the ignition point will approach 10 BTDC.

So , install it as per the book and once your engine idles in standalone at 600 + rpm you will have a rock steady 10 BTDC ignition point

The "retard " at cranking will ease starting a bit, and yes, I believe the Ford guys made this intentionally to aid starting.

Best regards

Klotzakk

Aha! That's an excellent piece of information I never read before. It is true that I never ran the engine with EDIS yet -- I have only turned the engine with the starter motor. And certainly the cranking was less than 400 RPMs. I will put the wheel back to standard position. Thank you!

Regards,
Bravin Neff

[Heribert]

Hi,
You are most welcome. Maybe you can, after having sorted uour install out, send a mail to the SiteAdmins and ask then to make an addtion on this in the Megamanual.
I have seen the behaviour on all EDIS 4, 6 and 8 that I hav used ( most be around 20 by now).

Best egards

Klotzakk