BDC

That's my guess! It all hinges on the 5V toggle output and how it works between each ECU. If they all work the same as the Haltech then it should work just fine.

B

BDC

Found this on Rotary Illustrated's website. It shows a visual of what factory leading waste spark is. This is stock on all 2nd gens and 3rd gens. Thankfully, Mazda got smarter and ditched it in favour of direct fire for the Rx8. For those of you that are engine minded you may find why I think it's a very bad idea for boosted and high power setups.

http://www.rotaryengineillustrated.c...s/an-IGN4.html

B

Claudio RX-7

iTrader: (1)

Basically it boils down to this, you CAN do this little trick if the EMS you are using is capable of controlling the stock ignition system like the factory ECU or the Haltech.

a_reyes1014

iTrader: (1)

thanks for the info bdc.

Indian

iTrader: (1)

good job B. Subscribed to

BDC

Yep. I bet it's possible on a stock car, too. I'm going to try it next on my black convertible (unmodified) and see what happens.

B

gxl90rx7

iTrader: (1)

correct me if Im wrong, but another way to understand why wasted spark can be a problem is if you are (for whatever reason) running retarded leading ignition beyond TDC. This would make the wasted spark ignite the other rotor's charge during compression = very bad

it seems to be a very worthwhile modification, and you would think you will be getting a more powerful leading spark, due to the fact it is no longer shared between two spark plugs

BDC

My guess is it's because it's firing a wasted, 2nd lead spark BBDC in the same chamber that's now a power stroke that's begun to lose pressure and expand. My guess is, among other things and for other reasons, it may be and may have been this entire time the silent yet never looked at killer of 2nd and 3rd gen engines.

BDC

Update: Been beating the heck out of my red Turbo II w/ this conversion over. No issues whatsoever. It's verifiably 100%.

B

slo

iTrader: (1)

Just noticed this when you bumped the thread and this makes sence, especially with your statment about hearing this from racers.

Some launch antilag systems work by systematicly retarding the ignition by a huge amount.

Outside a situation like antilag, I don't see how waste spark could be the hidden killer of rotary engines. In fact failed stock trailing coils on T2's is a not so hidden killer of rotary engines, when the coil stops toggling but keeps firing, therfore firing the front trail coil when it should be firing the rear .

BDC

If that were to happen while running a trailing ignitor w/ dual coils on the leading plugs (per this thread), then the symptom would be quickly known. Half the motor would basically stop working. But, that's a good point slo!

B

j9fd3s

iTrader: (3)

thats what i was thinking too.

fritts

iTrader: (5)

I'm sure this is the case. But it will be dependent on the coils used and whether a longer charge time on them will help produce a stronger spark. Specifically I would use this setup with a pair of ls-1 coils and then run the charge time up to about 6 ms instead of the 3 ms that a dual post has to run in order to not kill the coils.

Claudio RX-7

iTrader: (1)

With this set up you could probably improve the charge time to get better spark, but i would recommend using an oscilloscope with a hi current clamp to measure the ideal charge time in both this scenario and the a stock wasted spark deal. I have seen T2 coils with charge times of about 4.5-5mS, LS1 coils can go as high as 6mS in Direct Fire mode, they actually require it to maximize spark output, and then there's also the LS2 truck coil which is more powerful than the LS1, very good option to use if you dont wanna fork over hundreds of dollars on CDI boxes.

Hey Brian, have you noticed anything differently as far as driveability on this setup? Engine run noticeably smoother? What charge time are you using currently?

This is a really nice mod for E6K and E6X owners im sure.

BDC

I still think the most significant benefit here by far is the removal of a host of potential problems caused by having that wasted spark fire. I can't see anything possibly good about that waste spark whatsoever. Every scenario I look at with a leading spark firing at 30*BBDC to ~0*BBDC shows a possible production of some kind of knock.

Not at thing. That's how I know it works. Engine runs the exact same. The charge time I use is 4.8ms at the moment and I'm still using four factory trailing coils.

B

slo

iTrader: (1)

Hundreds of dollars on CDI boxes?

I have the summit racing 120 dollar CDI connected to a stock leading coil works so much better than the LS2 coils I was using, there really is no comparison. I actually bought 2 with the intention of using them sequentially.

Even have them both physically installed, they fit perfectly inside the stock FC bumper core, just haven't gotten around connecting them to the pair of aftermarket coils I got.

The difference is night and day, the CDI will idle the system both richer and leaner than the LS1 coils, in tunning the methanol injection it will continue running without stumble down into the 9-1 AFR range.

The only advantage that LS1 coils had was that they don't wear out the plugs as fast.

This CDI with stock components otherwise is cheaper.

fritts

iTrader: (5)

Did you use the standard LS-1 coils or the Truck coils? They really do hit much harder than the LS-1's. I'm going to see how far I can max the truck coils out. The CDI's are fine but they take a lot of room for the two boxes, require more wiring, a separate ignitor and aftermarket coils if you want to run sequential. The LS-1's or truck coils, for those that are not going to max them out make much more sense. You could try the MSD versions of the coils instead that would cost about the same and take up a lot less room and require a lot less wiring.

slo

iTrader: (1)

CDI boxes require little wiring, and as I said they fit neatly in the bumper core if you have one.

The ones I used were LS2 delphi coils (not the truck coils), they are better than stock, but not better than stock coils with a CDI.

The only thing I would use LS1 coils for in my car is the trailing. But instead I added an extra igniter to stock trail coil housing, because I don't like the toggle feature, it fits nice and looks stock.

tearbo2

iTrader: (2)

great job BRIAN (BDC) Y didn't I think of that ???? lol.....

all I will say is that ALL !!!!! high powered rotarys run seq ign waste spark is exactly that it is a waste and will cause nothing but problems at "high" boost
long story short, ive had a misfire w/ waste spark and had to rebuild the engine, ive had a misfire several times w/ seq spark and the wankel stays ALIVE !!!!!
I think all of the e6k owners need to thank bdc. for thinking outside the box



MAKE THE SWITCH !!!!!!

SEQ IGN

hIGGI

iTrader: (7)

Great work Brian!

Will there be a HOWTO for us lazier/less smart owners of E6K powered FC's ?

I sure can find some spare trailing coil and would like to try it out

Jobro

iTrader: (2)

HAHAHAHAHAHA BULLSHIT! The shared charge and fire signal is still sharing a single wire, you can't increase the dwell further than you could with the standard ignition system.


Yes BDC I have thought about doing this before, but I decided that sharing the single module for this task would mean no extra dwell time, and also the loss of waste spark which I think stops the backfire on throttle lifts after power runs. There are other 'BETTER' ways of doing it too.

#1 You could get 3 Standard Trailing Coil assemblies, wire trailing like factory. Wire 1 assembly to do the front rotor leading, tied the toggle wire to ground. Work out which coil always fires, and plug that into front rotor. Remove the other coil and keep it somewhere safe. Do the same with the other coil assembly for the rear rotor.

#2, Wire the leading plugs in waste spark using a trailing coil assembly with the toggle hard wired to ground as in idea #1. Next if you have an ECU that can change the trailing spark method to FD style (which is true sequential for the trailing plugs), you can hardwire the toggle wires to ground again, and then send the FD style trailing coil signal for front/rear into 2 separate FC coil assemblies. This method would allow double the dwell time on the trailing, but the same dwell time on the leading. I'm not sure how to get around the dwell problem yet. I will think about it more.

Of course my methods require 3 or 4 stock FC trailing coil packs.

Jobro

iTrader: (2)

PS Option #2 is fail proof in the sense that the trailing coil can never strike the wrong chamber in the event of a toggle failure.

fritts

iTrader: (5)

You're right on this setup you would be stuck with the same amount of charge. Forgot about using a single input but dividing by 2 to separate the firing. On true sequential though you you can run up the charge times.

junito1

Has anyone followed thru with any of this?

I have spare trailing coil assembly and 4 ls2 truck coils laying around.
Whats the best way to make this happen on e6x.

RX200013B

I'm hoping to have a answer to this question by the end of the month....