i was just talking to a friend of mine and i told him that we had to unplug the trailing coil pack because of ignition breakup on the dyno. then he says that he heard it's better that way anyway. i'm thinking wtf and then he says that he was talking about it with this guy in the east coast that supposedly invented a device that wires the trailing coil pack to the leading. my friend isn't one to lie so i'm wondering if anyone else has heard anything about this.

 

I've never heard of it, but anything's possible with Rotarys I suppose! :P

The trailing burns off excess gas and is basically there for emission as far as I know...

- Tech

 

I have only seen one in my life and that was at the last orlando meet the car seemed to run good not sure how he did it or why or if its better

 

no point, the trailing coil is more for emission and smooth running than anything else. disabling it will not gain you anything except more un burned gas traveling out of the engine.

And spark break up means that the spark is not happening... so why would you disable the trailing coils and have 100% trailing spark break up???

And spark break up really doesn't start happening until 6500 RPM anyway... out of the power range of any stock or near stock motor.

And some of the race engines use 3 plugs per rotor... not 1... that should tell you something right there.

 

hey icemark.

if you had the stock leading coil hooked to a Jacobs FC1000 or similar ignition amplifier, do you think it would be about equal or better than the stock system? removing the trailing coils would clean up the drivers side of the bay a little more.

 

Well, Ted and I disagree a little on that, He thinks a CDI system helps idle as well as top end, while I think it only helps prevent the spark break up on the high end.

But then I use the normal operating temp plugs most of the time.

So to answer your question, IMO a CDI makes the stock system better for extended high RPM operation, but I would never expect it to make up for the trailing coil spark.

But again, I see no point in removing the trailing coils. It is a waste of time, and the engine runs better with them.

 

put well enough. the trailing stays.

 

i want to keep my trailing, but we were getting ignition breakup when the car was getting tuned on the dyno. after disconnecting the trailing everything was fine. i changed the spark plugs and borrowed some trailing coil packs to hopefully fix this problem.

spark break up was happening in the higher rpms and my motor isn't stock. after unplugging the trailing it pulled 309 rwhp on 6 psi.

which is why i want to get my trailing back. i have an msd 6a on the leading and i'm looking into 2 more for the trailing if it will fix the problem.

 

KDR started this Anti-Detonation Device crap.
All it was was to remove the two trailing plugs and disable them - then they inserted a machined plug to cap the trailing plug holes.
They claimed by not firing the trailings, the mixture stays richer and supresses detonation.

What a bunch of bullshit.
You can do a keyword search on "anti detonation device" and read about it yourself.

Would you pay $400+ for a couple of plugs???

Mazda claims up to 10% of the power is produced by the firing of the trailings spark plugs - it's in an SAE paper.
It is primarily there to clean up emissions and burn the mixture more completely.

If there is ignition problems, it's not the trailings plugs that are firing that is causing the problem - look elsewhere.
On a properly running 13B, the trailings do not induce more ignition break-up cause of the trailings spark plugs firing.


-Ted

 

when i was talking to my friend he made it sound like the device wired the trailing coil straight from the leading so it would be like running 2 leading coils, but i could've misunderstood.

the car runs perfect with just the leading coil. when the trailing coil is plugged in everything runs fine until the higher rpms. the person tuning it thought i wired the microtech to the trailing backwards, but when i checked it was right. one of my plug wires was wedged between the alt and fender wall... i don't know if that may have had anything to do with it.

 

Yep, that's another variation of the same theory.

What it comes down to is it tries to cover up poor tuning, period.


-Ted

 

Question for you guys,

I've got a little issue past 7,000 RPM...SonicRAT said he thinks it's spark break up, which I cleaned the plugs off and it still does this.

It did the same thing my first generation did at high rpms, but I could also advance the timing on it (SE) and it would disappear...

So with that being said, is it normal for that high rpm bumpage to be there (ie 7,000 to 7,200 bogs, 7,200 to 7,500 is normal, 7,500 to 8,000 RPM is bogs again)...

Will a aftermarket ignition (MSD, whatever) solve my problem or do you think it lies somewhere else?

The SAFCII is set on 0% correction all the way across the band to make sure that wasn't the problem...

 

how much power can the stock trailing coil pack handle before cdi boxes are needed? i want to fix this break up problem before the next time i go to the dyno.

 

Didn't you just make 309whp @ 6psi? Impressive **** man!

 

thanks! blame dave... he did the tuning.

 

lemme clarify this...

it wasn't ignition breakup on the dyno... i think the trailing coils were either wired incorrectly, or some other problem, but it was misfiring...not breaking up.

the reason i tried unplugging the trails was just to test that... it worked and i didn't want him to waste a trip all the way up here, so we went ahead and tuned it on just the leading. i said add ~5ish hp to whatever the number was once the trailing gets figured out right.

ted, i think you misunderstood the "safe" zero split. i've heard of that before. basically, you'd wire both leading and trailing coils to the trailing lead and turn your split down to zero. this would give you zero split without the chance of the trailing firing before the leading. this isn't the same thing as the "anti-detonation device" in any way, shape, or form.

 

my bad... i must've misunderstood one of your pms and did some searching on ignition breakup.

 

Hey dave was his ignitino break up like mine when i was dyno'ing?

 

Well, it all basically does the same thing.
It removes one "set" of spark events in the ignition timing.
In fact, removing the leadings and just firing the trailings (at 0 split), 1) removes the trailing spark event (duh), and 2) eliminates the "far trailing" spark event that the wastespark'd leading used to do.

If the trailings are firing before the leadings, there is something seriously wrong (ignoring that thread that uses this method for off load ranges) -> bad tuning or bad wiring.


-Ted

 

now you're assuming the ecu to be 100% reliable, 100% of the time, right? anyone here trust their ecu to actually turn their split down to zero and go for it? it's got nothing to do with tuning.

the "safe" zero split is a way to have the advantages of 2 plugs per rotor, without the possibility of the trailing firing first.

anjew, this wasn't breakup. it was a misfire. whenever jeff wakes up he'll get my pm and we'll see if he can get the car up here today or sometime soon and we'll get the trailing figured out. i bet 10 minutes and a timing light will fix the problem, but there's only so much diagnostic stuff you can actually do on the dyno.

 

MSD + Megasquirt. Hey look, all you're problems are solved!!

 

megasquirt or microtech... which one's worse?

 

And you're assuming you can adjust split?

How many people in this thread do you think are running a stand-alone EMS?


-Ted

 

quit trying to pick a fight. you didn't have a basis on technical info, so you're resorting to semantics?

go fight someone else.

 

Dude, why you getting all defensive?
99% of the folks in here are running on stock ECU's.
This thread has no use for them.
I just wanted to state that explicitly before we get a bazillion threads asking how to do this and adjust trailing split...
duh


-Ted