Ecomodding a 2.3L fox body mustang. Project "show me the carfox"

[RobertISaar]

also, in case you've never done so, unplug either coil pack's main connector. one will cause the engine to never fire, the other will allow it to idle. the "no fire" on one is due to only one pack being used while cranking, it comes online once the engine is running.

anyways, with only one coilpack alive, you'll make about enough power to hit 40MPH and that's it. this system was designed around both being functional, if not, problems occur.

[RobertISaar]

Originally Posted by R.W.Dale

I just an a couple tests.

No1 on the rear coil (run side) is firing on the mark with about 20 degrees of advance dialed in

On the wasted spark coil number 1 or 4 is also on the mark with the same advance dialed in

Now what I need to determine next is are the two #1's firing together or are they firing 180* out of phase

you answered your own question. if it were firing 180* out, then your timing light would fire with the timing mark on the other side.

[R.W.Dale]

It would appear as though your correct. Complex stuff aside when I think about it swapping 1-4 and 2-3 would do absolutely nothing because of one of the fundamental ways DIS systems work.

Focus on 1-4 here

As you note they're on the same individual coil. When that coil fires it naturally fires towards the spark plug experiencing the highest pressure through the head across the gap on the opposite plug (weaker this time) and back to the coil. Then it swaps direction on the next firing because a different coil is under compression. Which cylinder is under compression determines which fires not whatever plug wire is on what end of that coil.

After pouring over this and with your input its my belief that swapping 1/4 and 2/3 on the passengers side coil (or any coil) will do absolutely NOTHING good or bad. That coil will still fire the same plug at the same time it'll just do so on the opposite terminal

[RobertISaar]

depending on how the wires are swapped around, yes. if you swapped the wires around so that one coil fired both plugs on a cylinder, then problems can start popping up, since instead of having two different coils providing a strong + waste spark, you'll have the coil alternating between firing two strong plugs and two waste plugs, which will certainly show you if a coil is weak, since it will do just fine for the waste events but fall short for the strong events.

Ford set it up in what i would consider an optimal arrangement on all fronts. i don't see any possible advantages to firing it the way some have suggested in the past.

[ksa8907]

Perhaps I don't understand how the system is wired. I'm assuming it is electronic ignition timing from what I'm hearing. Cant you just bridge the signal wires from one coil and feed them to the other?

[RobertISaar]

Originally Posted by ksa8907

Perhaps I don't understand how the system is wired. I'm assuming it is electronic ignition timing from what I'm hearing. Cant you just bridge the signal wires from one coil and feed them to the other?

there is no need to. they already operate in that fashion at all times except for when cranking the engine.

based on both factory docs and what has been tested, both coils are operated at the same time for a given cylinder.

both 1/4 coils charge and fire
both 2/3 coils charge and fire
both 1/4 coils charge and fire
both 2/3 coils charge and fire

that's how the factory doc is implying it and it would appear that is exactly how they function based on the timing light.

[Arragonis]

Just popping in to wish good luck and to observe - also trying to ecodrive an auto...

[Occasionally6]

There may be some truth in the origin of swapping the wire leads from 1-4 and 4-1, and 2-3 and 3-2. (That is what is being discussed isn't it? It got a bit hazy for me.)

Any waste spark ignition system will be firing one of the spark plugs in each pair from tip to ground and the other from ground to tip. The spark plugs erode accordingly.

It is easier to fire a spark from a sharp point or edge, such as from a nice square spark plug tip, than from a rounded, eroded surface.

If you have car with spark plugs near the end of their useful life and swap the leads, the direction in which they fire is reversed and there are fresh edges for the spark to jump from, improving the ignition.

Maybe not, but does it make sense?

[RobertISaar]

the spark likes a sharp edge on both sides of the gap.

it MIGHT have some effect, but i'd rather just change the plugs out.

[Mustang Dave]

Welcome aboard, fellow Mustang owner! I know from my own experience that it's possible to average over 30 MPG commuting with a 4 liter V-6 S-197 (2005-2009) Mustang. The mods that made the major differences in fuel economy were "adjusting the nut behind the steering wheel" and adjusting my commute route to eliminate driving @ 75 MPH (or driving @ 65 MPH in the 75 MPH speed limit areas). I live in northern Arizona - rarely need A/C unless I have a passenger.
Best of luck with your project.