Ok so I know people say there's really no advantage to it but Id really like to use 10mm FD wires and not have to worry about finding a 10mm wire to run from the stock coil to the dizzy. So I figured I could just find a 2g trailing and mount it under my 2g leading coil but while searching I read that you could just get rid of trailing and retard leading 2 or 3 degrees. Which would be the better way to go?

 

yes it will run just fine without trailing. but no need to retard the leading.

 

Will ditching the trailing make it run ritch?

 

Here's a few examples that showed up at the Lake House:





http://www.youtube.com/watch?v=kwKlbX0DSRk

 

Is it true that if I drop the trailing I'll lose my tech?

 

your tach should run off of the leading. I ditch my direct fire and went back to my MSD running the leading coil. Didn't see the difference on the dyno.

 

Yeah the direct fire coil isn't really gonna give you more hp but for the 12a it should give you a smoother idle and maybe better throttle reponse. Not sure about the 13b though. Ok so would it be better to just drop the trailing than to go direct fire trailing?

 

84-85 if you drop the loose trailing you lose your tach signal and also fuel pump, but SA to early FB's you should be fine.

 

Direct fire will help a lot with smoother revving and easier starting. Running no trailing will not
make you lose gas mileage (since the gas is already in the chamber) but it will smell a little rich.

If you plan on running just leading you can advance your timing further than if you were running
trailing as well.

I have a MSD6T box triggering 2nd gen leading coils, no trailing. Didn't start the car for about 8
months and put on a poorly tuned carb, started after the 3rd revolution.

EDIT: http://www.youtube.com/watch?v=cON1DU_5oDU

 

you still get 2 sparks per rotation witn only a 2g coil. since its batch fired so I wouldn't think it would make much differance as far as afr's go. I have mine advaced quite a bit also,

and I like the direct fire, my car only shoots flames if I stay on the secoundarys for longer than a few secounds. where before it just shot flames randomly. on 83's you lose the tach if trailing ignitor is dead. but I think it always worked when I bet people I could run my car with the cap and rotor off. easy money.

 

Yeah my cars an 83 but my engines a 79 so I guess the tech should be ok.

 

A lil off topic but in this pic how do you move the alternator over to where the a/c used to be?

 

alternator relocation kit, i forgot who sells them ...mazdatrix maybe?

 

Sweet! I'll have to look into it

 

Double spark usually ends after 3000 RPM (atleast on MSD's), there just isn't
enough time to energize and fire twice per chamber at that speed.