I know there are a few of us using these coils,
http://www.diyautotune.com/catalog/i...oil-p-394.html
http://www.034motorsport.com/product...roducts_id=277

Ive always seen the charge time gets reccomended at 2.5ms-3ms. we checked them with a scope today and output kept climbing up to almost 9ms charge time, the output was roughly 3x what it was at 3ms charge time. We settled on using 7.5ms charge time as it was close to 90% of the peak output.

Time will tell if the coils will last with such long charge time, I was/am a little hesitant with it as it seems odd to be so far off the "reccomended" settings.

 

it was late when I wrote this last night, when I said output I meant the coils kept accepting charge untill almost 9ms before saturation. Even then the graph wasnt totally levelled off, but the curves slope wasnt nearly as steep, decided to call it good. Im sure the extra charge time bumps up the output of the coil, but I have no idea how direct the relationship is.

These coils probably pack way more punch than most get out of them, if anyone else has access to a scope I would be interested to see where they find saturation. And again if the reliability will still be there.

 

when you see 3.0 - 3.25 ms settings ,, the tuner is aware the ECU may be wastespark leading
and hence coil dwell periods represent the maximum avail charge period when the engine approaches peak revs

ie,, at 9000 rpm,, you have 6.666 ms avail for each combustion period
in which wastespark leading must rest, charge and fire TWICE in that period
so therefore charge period reflects less than half of the avail combustion period
( and then coils with very low primary resistance chosen to suit that ! )
[ so they can get a decent energy up within that period ]


by choosing such an excessive charge period as you have
- you must be aware that your ECU MUST NOT be set in wastespark mode
( ie be fully sequential ignition )
and that the final dwell period you choose is not less than the combustion period

ie,, 6.25 ms max for an engine known to pull to 9000 rpm powerband

 

I've never put a scope on them but am curious to do so now. I've always taken the advice of the few people that are selling them that are saying no more than 4 ms and 3 ms should get you a 90% charge. I've run 24 psi with methanol injection and 22 psi with water/methanol with these coils are less than 4 ms and never had an issue with ignition. They've worked very well. And those values are not influenced by a consideration for a wastespark setup.

What was your input voltage while testing?

 

I didnt pay attention to the input voltage. We checked it at idle, 900rpm, and again at about 1750rpm. The graph on the scope looked nearly identical at both rpms. The car should have been putting out 13.5v at 1750rpm, but again I didnt pay attention.

As for the wastespark comment, thats a good point that people running wastespark need to consider. Im running direct fire and Im told that the haltech, or at least the sport series, if needed will automatically scale back the charge time as the rpms raise.

 

If the input voltage is low it'll take longer for the coil to charge. If you have time check the voltage at the coil.

You're correct on most ECUs scaling back the charge time. That's what makes this coil so attractive in the rotary application though is that it's supposed to require a short charge time relative to the LSx coils so, even when used in wastespark, it's still possible to get a complete charge without driving the thing at near 100% duty.

 

Checked with a volt meter at the coil, lots of voltage.
cold idle 13.6v
hot idle 12.2v
hot 1500rpm 12.9v

 

Check vs battery voltage, if battery voltage is 14 (for example) and coil voltage is less, then start looking to voltage drop. Looks a little low to me.

 

It looks low because of underdrive pullies. Its the same as batt voltage.

 

That'd do it.

 

This needs to be moved to the EFI101 forum. Let Lance "The Wizard of Odd" think about it for a while.