I just did DLIDFIS on my '84 GSL-SE...The original writeup said to move the trailing wires on the D.cap to the leading positions. Do you also move the wire from the trailing coil from it's original position(T) to (L) also, or leave the coil wire alone and just change the plug wires on the cap? It starts and runs either way, but seems really "quiet" (exhaust)and slower revving with the Trailing coil wire in its original position. When I moved the coil wire also, it seems "louder" (exhaust) and really lacking in acceleration, also I still get backfires...Which is the correct way to do it? What about my vacuum advance now?

 

i did this swap on my DD 85 GSL. i used a 2nd gen coil for the leading. all i did was swap the + and - wires from the stock coil to the 2nd gen coil and swap the spark plug wires. after that all i did was swap the trailing wires on the dizzy cap. i put ALL T wires in the L position. that includes the one from the coil.

i still have my vacuum advance hooked up. id advise just doing a recheck of the timing. unhook the V advance and plug it at the dizzy and carb. then check the timing. id also go through and make sure all your connections are good and everything is wired up properly.

id did this and noticed a change in the exhaust not, but the car drives great. this is really a very simple mod to do. id advise using the 2nd gen coil though.

 

When I did DLIDFIS ('83 12A), I didn't touch the trailing. Wanted it to be easy to go back to one ignitor on leading if I had a problem on the road.

- David

 

Since the main purpose of the trailing plugs is to help achieve a more complete combustion for emissions purposes, you won't notice a difference if you've wired your trailing properly or not.

The main reason they say to switch the leading to the trailing spot on the dizzy is because if you look under the cap, the leading parts are much beefier than the trailing parts of the rotor/cap. Just better for conductivity really.

So yeah, you can either leave trailing as-is, or you can switch your trailing stuff to the leading spot on the dizzy by moving all T spots to their equivalent L spots.

For the folks who've added the FC coil, what did you use for wires between the FC coil and the spark plugs? Did you have them custom made? FC wires? FB ones?

Jon

 

This mod will change my timing? Or is it that the vacuum advance for leading no longer works because leading is not running through the cap? Before I did this, I asked around here and everybody pretty much said timing wouldn't be affected. Also, won't the timing flashes for the leading double(two coils now)? How would you read it? My car is harder to start when warm, and the exhaust tone has really changed, and it kinda spits and sputters(a tiny bit) when trying to drive at low rpm's (<4000). Is this normal? I expected a noticeable improvement in acceleration and had hoped the backfires would dissappear...I've noticed neither. What do you guys think?

 

Just thought about it, since I completely rewired everything to do with the ignition, is it possible my T1 and T2 spark plug wires are switched around? Would this explain my symptoms? The two plugs towards the front of the engine, are these 1's or 2's? Right now, the trailing plug towards the rear of the car is T1...Are the back plugs 1 or 2? I forget!

 

This mod doesn't change timing. Timing changes when you rotate the distributor, or when the vacuum advance moves the stuff inside the distributor. Your leading wires no longer go through the distributor, but the magnetic pickup inside the distributor triggers the igniters. DLIDFIS is a lost spark system- both leading plugs fire at the same time, but the rotor isn't in the right position for one of them to do anything.

Since I changed mine to DLIDFIS, it starts better (hot or cold), runs better, and winds higher than before. Greatr all-round improvement.

- David

 

1 is front, 2 is the rear.

 

I've never understood what advantage this setup would yield without having some way to seperate the signal from the L1 and L2 coils. When you move the trailing wires on the dizzy, this changes nothing. I've been running the 2GCDFIS w/TT and locked dizzy on my turbo FB for about a year and a half with no problems, and I've been running the 2nd gen direct fire coil on my NA track car with no problems. I've always wondered how this could be a benificial upgrade on an ignition with a dizzy? Wierd.

 

no this wont change your timing. it was just an idea. more so incase you decide to "fiddle" with it while doing the mod. if you didnt, then dont worry about it.

id check to make sure everything is wired up properly, im 99% sure thats your problem. honestly, id just switch to a 2nd gen coil teh first chance i got makes thing simpilar and is supposedly better. i know i love mine.

the spark plugs from the drivers side go as follows:

top left- T1
lower left L1
top right- T2
lower right- L2

im using the stock FC wires without any issues.

 

Thanks alot for the info. and input, guys. I finally found a wire that broke at the crimp-on connector inside and was giving intermittent 12v to my one leading iginitors...Made a new wire, everything is great! Exhaust is quiet again, and no more smoking/ backfiring from the unspent fuel! Awesome low rpm city driveability, also!

 

Good to hear.

You should still re-time it anyway. Just to be sure. You never know what variables change when you go from one system to the other...

Jon