cool, thanks for the detailed explanation. How about the AEM? Do you know how that one works? Is it similar to the MSD?



Thanks

Bob

 

The AEM C2DI is slick - very powerful and will handle lead+trail with one

box. There is a switch to configure the unit for coil per plug or

waste spark. In coil per plug, each channel is basically a 1 cyl; in

waste spark each channel is a 2 cyl. For the rotary, it would be set

to waste spark mode so the trails channels would work fine. The lead is

going to get only 10 degrees of sparking though, because it is essentially

a 4 cyl coil.

AEM just emailed me the instructions today - I'll have to forward it to

my work address because my pdf viewer at home doesn't like the file

(won't let me see the pics, and now won't let me read the config switch

paragraph either).

 

With the AEM evryone says to leave all the switches off. So using this with the anti det device, where you are not concerned about the trailing, the switch should be set the other way to provide the 20 degrees of spark on the lead coil, correct?



Bob

 

83turbo i have the instructions scanned if you would like them.

 

Switch functions:

S1 - Multistrike. If this one is off, the ignition operates in single strike mode, so the whole firing window issue is moot.

S2 - Trigger edge - depends on whether you are triggering from the factory ignitor or straight from the ECU

S3 - Wasted Spark - "Off" causes the unit to assume an individual coil every 720 degrees (coil per plug). "On" assumes wasted spark with 2 cylinders per coil (360 degrees per event). The trail side on the rotary fires every 360; the single lead coil every 180. Assuming multistrike mode (S1 on), I would turn this switch ON - the trails would get 20 deg, and the lead 10 deg.

S1 OFF would yield 10 deg on the trail, 5 on the lead.



To get 20 degrees on the leading, you would need to set up a true coil per plug on the leading (ie each plug fires every 360 deg, like the trailing does). Some ECU's may support this directly. It could probably be done on an FC by wiring a spare trailing ignitor into the leading side, and sharing the "select" wire. I believe the FD ECU has discrete T1/T2 outputs so the same trick would work unless you are able to re-map the trail outputs to give timing appropriate to the lead plugs (maybe the PFC can do this?)







rfreeman27: I managed to print it out at work - thanks anyway

 

yep, pfc lets you independantly adjust the timing of the trailing so I basicly would just put my leading map over the traing essentially making it appear as though there was zero split. The only issue I forsee with this is possible Idle learning problems, but if I had to I could just manually tune the idle.



Bob

 

83,

I was just reading the instructions for the AEM, they say that swith 1 is the multifire disable, so if you turn that on it will disable the multistrike feature. So wouldn't you want it off then, to get the full use out of the box?

 

According to my instruction sheet, S1 off disables multistrike; s1 on enables multistrike.

 

maybe we have a different manual?

 

Mine says:

Switch 1 - Multi-Strike - S1 enables or disables multistrike plug firings. Disabling Multi-Strike (s1 - Off) makes engine timing much easier to check. Enabling Multi-strike (S1 - On - Default) makes the engine run smoother at low speeds.





I wonder if there are 2 different versions of the box to match the 2 different manuals?