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I currently have a Ludwig harness that was wired for wasted spark that I plan on using for the time being and was wondering how I could best us the variable dwell settings that came with Wari V14 to get the most out of the coils while in wasted spark.
As I have not altered my ignition from stock prior to now I am unsure of the limitations of the AEM coils past what I've read on here. I've concluded that in wasted spark the leading coils can run a max of 3400 ms as with this dwell time at 8000 rpms they are still within the recommended max duty cycle of the coil. While this would have have been a set figure for constant dwell vs rpm in previous versions, V14 allows for variable dwell such that I could possibly run 4500 ms at the lower rpms and then taper it down to 3400 ms at higher rpm levels.
I'm looking for some guidance on setting up the table so that I would remain in a safe area but get the maximum out of the coils. Any help or suggestions would be much appreciated. Thanks!
Good thread, I currently run the AEM smart coils as well and have converted to Direct fire. I still have not messed with the V14 dwell times either and would love to know a better way to set it up to maximize the coils.
If you have converted them to direct fire and set up the ECU correctly, you can chance the dwell time in the map above to 4500 microseconds. From what I've been able to gather on here, it has been confirmed that when then coils are running in direct fire at 8000 rpms they will still be within the duty cycle limitations set by the coil manufacturer. I don't think you'll see any gain by using the variable dwell table as you will be able to run 4500 ms across the board.
On the other hand, with the coils in wasted spark, you can only run around 3400 microseconds of dwell because my leading coils fire twice as often and at 4500 microseconds would put me well past the duty cycle range at 8000 and will essentially kill my leading coils.
I got my coils installed and am currently troubleshooting why I'm not getting fire. Another annoying issue is that for whatever reason my fans want to come on anytime the positive battery cable is attached to the battery terminal.
I also have all the diagrams of wiring looms and what not if you need some help hunting down the problem. I had gremlins all in my electrical when I bought mine.
I got the issue sorted out which turned out to be due to a grounding mixup. The car then started right up and is running fine in wasted spark with a dwell time of 3400 microseconds.
I'm still looking for an answer on how the variable dwell table should be setup. I find it hard to believe that after 300 views on this thread nobody knows the answer. Hopefully a tuning or ignition expert can chime in here and give a recommendation.
FYI: ms usually refers to milliseconds, which obviously will not work.
When referring to microseconds (as in WARI) then us or spelling out microseconds would be better.
Thanks!
I'm familiar with the Greek letter mu and that it is the prefix for microseconds however as it isn't commonly available on the english keyboard writing ms and saying microseconds in conjunction with the abbreviation should serve my purpose.
That being said, nobody has been able to advise on the meat of the question. I'll post what I find eventually after I sort it out.
Here's what I'm going to run. Give it a shot. It never exceeds 40% duty cycle, as per recommended by AEM/Mercury/Andy himself.
3400ms is too much for 8k RPM, it should be 3k. Follow this stepping for higher RPM applications as well...
Thanks for the table! I searched all the forums and could't find anything similar to this.
Originally Posted by C. Ludwig
40% is the max continuous dwell. You can lean on the coil at higher revs a LOT harder than what you're showing in that dwell table.
I was actually hoping you'd chime in on here! I wish there was a way to tag a person in a thread. How much more would would they be able to take in the higher rpm levels? I'm going to update to the dwell in the table listed above and then add dwell up top based on what gets said here.
40% is the max continuous dwell. You can lean on the coil at higher revs a LOT harder than what you're showing in that dwell table.
From what I understand, it's around ~3ms spark duration + 3ms dwell time @ 8k RPM = 6ms. This is 80% duty cycle. Considering that's the tolerance that I run my injectors to, I'd have to rebuild this for each cell.
From what I understand, it's around ~3ms spark duration + 3ms dwell time @ 8k RPM = 6ms. This is 80% duty cycle. Considering that's the tolerance that I run my injectors to, I'd have to rebuild this for each cell.
If that works for you, fine. But dwell is dwell and discharge time isn't part of the equation. At the end of the day, this coil is still plenty hot at 3ms. So more may not be needed. But, if it is, there is more headroom, even in wastespark.
Further, FWIW, discharge time isn't a constant. It is effected by a variety of conditions including plug gap and cylinder pressure.
If that works for you, fine. But dwell is dwell and discharge time isn't part of the equation. At the end of the day, this coil is still plenty hot at 3ms. So more may not be needed. But, if it is, there is more headroom, even in wastespark.
Further, FWIW, discharge time isn't a constant. It is effected by a variety of conditions including plug gap and cylinder pressure.
What would you recommend for target values instead? I'm going to initially run a 9 heat range plug and as I tune in higher boost pressures with e85, most likely go up to 10.
Wanted to report back to this with some real world feedback since I've been running these coils with the settings advised.
I've been running the car in wasted spark with the settings shown here for a few months now with no issues. It definitely seems to fire harder on a cold start and idle smoother than it did on the oem coils. It may all be in my head, but I do seem to notice that the car is less finicky off idle and it seemed to help with some of the twin-disc-engagement stumble.
I'm going to pull my plugs this afternoon and see what condition the tips are in after some time with the higher powered ignition and post some pics if they are interesting. I've got a fresh set of NGK R7420 10.5's and 11.0's on the way now which will be replacing the set of Autolite AR3932X plugs I've had in the leading spots and the oem 9's I've had in the trailing. I'm half expecting that cheap autolite plug to be shot.
I'm still debating going the direct fire route and was wondering should I choose to do so how the variable table could be set up to reflect the coils' abilities when in direct fire. Any suggestions or math on this would be much appreciated.
I would really like to know how to make the calculation myself so I could sort out my own values for both wasted spark and direct fire, however I've seen online the calculation done several ways, which leads me to believe one is wrong.
Wanted to report back to this with some real world feedback since I've been running these coils with the settings advised.
I've been running the car in wasted spark with the settings shown here for a few months now with no issues. It definitely seems to fire harder on a cold start and idle smoother than it did on the oem coils. It may all be in my head, but I do seem to notice that the car is less finicky off idle and it seemed to help with some of the twin-disc-engagement stumble.
I'm going to pull my plugs this afternoon and see what condition the tips are in after some time with the higher powered ignition and post some pics if they are interesting. I've got a fresh set of NGK R7420 10.5's and 11.0's on the way now which will be replacing the set of Autolite AR3932X plugs I've had in the leading spots and the oem 9's I've had in the trailing. I'm half expecting that cheap autolite plug to be shot.
I'm still debating going the direct fire route and was wondering should I choose to do so how the variable table could be set up to reflect the coils' abilities when in direct fire. Any suggestions or math on this would be much appreciated.
I would really like to know how to make the calculation myself so I could sort out my own values for both wasted spark and direct fire, however I've seen online the calculation done several ways, which leads me to believe one is wrong.
Cheers! Thanks in advance.
-Skeese
I actually calculated this for direct fire, but wasted spark uses the coil more, which would have shown more wear (heat) on the coil itself.
Glad it's working out for you as I had planned. It's going to be my baseline for the coil setup. I'm sure you could push the coils harder, but why **** with reliability?
I have been running this setup for the initial breakin of my rebuild on the sakebomb kit this is only after 500 miles. These are leading plugs 9 heat range just for reference I've included a fresh plug. I'm running rich until I can tune it but these coils eat plugs.
Right now I'm running 7s and 9s but will probably have to go to 4 9s once it's tuned to a comfortable limit
Last edited by David_raz89; 03-26-16 at 01:51 PM.
Reason: Add info
I have been running this setup for the initial breakin of my rebuild on the sakebomb kit this is only after 500 miles. These are leading plugs 9 heat range just for reference I've included a fresh plug. I'm running rich until I can tune it but these coils eat plugs.
Right now I'm running 7s and 9s but will probably have to go to 4 9s once it's tuned to a comfortable limit
the settings work great but unfortunately I'm haveing ign breakup at 5800-6000 I think from it being too rich but the more fuel I take out the more the trim adds I just need to find a dyno, doing this on the highway is getting old.
the settings work great but unfortunately I'm haveing ign breakup at 5800-6000 I think from it being too rich but the more fuel I take out the more the trim adds I just need to find a dyno, doing this on the highway is getting old.
I haven't experienced any breakup in this region, but I am running the stock NGK 9's in the trailer spots and the AR3932X plugs in the leading spots. The AR3932X are supposed to be close to a 10.5 plug, but I only read that somewhere on here and have nothing solid to verify that.
You want to tune the boost region of the fuel map in open loop and then run closed loop once the map is extremely close if you plan to use it. The closed loop fuel control will continue to trim fuel to keep you on the target AFR if you pull fuel out of the table and I find that make any fuel changed based off readings taken in closed loop while the fuel trims are being applied is extremely inaccurate and that there is no way to accurately gauge what the map really needs without being in open loop.
I plan to actually get around to pulling my plugs tonight and will report back tomorrow.
I am super terrified of running open loop and popping my motor my wife would kill me after all the time and money I put into that motor living in the middle of nowhere Wyoming sucks when it comes to competent tuners on anything other than a wrx
I haven't experienced any breakup in this region, but I am running the stock NGK 9's in the trailer spots and the AR3932X plugs in the leading spots. The AR3932X are supposed to be close to a 10.5 plug, but I only read that somewhere on here and have nothing solid to verify that.
You want to tune the boost region of the fuel map in open loop and then run closed loop once the map is extremely close if you plan to use it. The closed loop fuel control will continue to trim fuel to keep you on the target AFR if you pull fuel out of the table and I find that make any fuel changed based off readings taken in closed loop while the fuel trims are being applied is extremely inaccurate and that there is no way to accurately gauge what the map really needs without being in open loop.
I plan to actually get around to pulling my plugs tonight and will report back tomorrow.
I'm just bummed that you guys are using my setup and not one of you has commented on my build log with experience, suggestions, criticism, etc.
But...all is well in the world. Fuel tank stuff and rear end stuff should be done by April.
I am super terrified of running open loop and popping my motor my wife would kill me after all the time and money I put into that motor living in the middle of nowhere Wyoming sucks when it comes to competent tuners on anything other than a wrx
PM Incoming. I understand your fear, I was in damn near the damn situation for a while and I was doing the same as you. I can help you safely get around some of that. It really isn't that bad and so long as you set up the engine protection stuff before you start tuning you have nothing to really worry about.
Originally Posted by SirLaughsALot
I'm just bummed that you guys are using my setup and not one of you has commented on my build log with experience, suggestions, criticism, etc.
But...all is well in the world. Fuel tank stuff and rear end stuff should be done by April.
I'll check it out! I hardly ever read build threads on here, nor do I ever actually update mine, however I do daily update/chat/talk/post on a local forum and it is way more fun. It seems that nobody on here cares to read a build thread unless it is a twin turbo 4 rotor or something totally nuts. Mine is like talking to myself.
01-08-16, 01:20 PM
