Found this in FC section. Very cool and would be easy to do in FB.

For people not wanting to read it - Basically with 2 step button activated, that button also activates a relay which in turn kills power to trailing coil (relay set to always closed and then triggers to open).

https://www.rx7club.com/2nd-generation-non-technical-pictures-198/single-msd-two-step-%2Awrite-up%2A-888764/

 

I'm not quite understanding how killing your trailing gives you better launches in the 60ft range...

 

You can blow right past the rev limiter on trailing alone, so you disable it.

Or you do what I did. Just run both ignition systems off of one MSD box. Simple.

 

Another option (what I would do)

Leading only, MSD box

Using the Magnetic pickup for the trigger, you can use the white wire to ground and cancel.
Have a shift light hooked up to where the relay would trigger a ground, not firing the ignition
until the rev's dropped.

 

Peejay - Running both T and L off one box means zero split correct?

Edit - My plan is to run DLIDFIS minus trailing so I would then only need 2 coils and have a handy spot already for them to be mounted. I saw this idea and thought maybe someone else would be interested if they wish to keep trailing for emissions, or whatever (weekend warrior type car).

 

I feel like I am missing some part of this conversation.
I'm still a little lost as to why removing Trailing gives you a performance increase, I thought that the trailing helped the burn be more efficient which would result in a better amount of energy released from the charge.

 

Or spend even less money and run the dlidfis with this setup like me.... Its cheapest/easiest way to get 2step that im aware of and is a very soft cut.




I only have it setup on the leading side.

http://www.youtube.com/watch?v=gKT4UJ9fh-0

Car is not mine (its an fc obviously) but is running the same setup.

 

A 2-step is a two stage rev limiter. With the clutch switch (or whatever) closed (or whatever) then the rev limit is X, with it open then it is Y. Assuming you run one, I don't.

The idea is that you can launch at a preset RPM every time.

If you only have one MSD box, you either need to disable the trailing ignition, or run L&T off of the same box (which will give you zero split), otherwise the engine can and will run right past the limiter on trailing ignition alone.

IMO, if you're not using some form of multistrike CDI, messing with the ignition system is just screwing around.

 

Ah, this makes sense now...