RX7TR7

About 2 months ago my trailing Ignitor went out, and I wasnt working and almost broke. I tried to go cheap and buy them used but got screwed on two used ones on eBay. Then I came across a few posts where guys used GM HEI ignition modules to trigger DLIDFIS. So I figured why couldn't I used it just to trigger one coil until I could afford a new Ignitor. So I hollowed out my old ignitor and used it to make a connector, then wired up the HEI Module. I was impressed with how much stronger the spark is from the HEI module as opposed to the Mazda Ignitor.

I think I have the pick up wires going the right way because my timing is correct. If I reverse them, the timing is way off. The problem I am having is it is missing at idle and my tach flutters between 1,000 and 2,000 rpm. Over 2000RPM the needle is steady. If I disconnect the Module the Miss goes away but then my trailing coils don't fire, if I leave it connected it misses. The module is grounded to the body of the car with 2 self tapping screws, I got the power from the coil feed wire, the old ignitor is gutted and basically a jumper from the pick up coil to the 2 terminals on the HEI Module, and the other terminal is to the ground on the coil. The coil wire still goes to the distributor and then out to the 2 trailing spark plugs, same as stock. What did I do wrong?

t_g_farrell

iTrader: (1)

Is this an FB or an SA? Dizzy are different and the SA one doesn't work as well as an FB one.

Otherwise I would think its maybe noise. How long are the leads bringing the dizzy signal to the HEI?

I have a link in my sig to my write up on how I did this. You may have seen it already.

RX7TR7

I think your write up was the last one I looked at, the only way mine differs from yours is I used the mounting screws to ground it to the body as opposed to a ground lead. Im using a 4 pin module because I had it and I am still using the stock ignitor for the leading coil. The car is an 82. It is the distributor with the 2 J109 ignitors screwed to it. The leads from the distributor are actually from a MSD jumper that went from the box to the distributor I cute the plug off and put terminals on the end to hook up to the ignitor and HEI Module. I dont have a tape measure handy but it is between a foot and 18 inches long.

t_g_farrell

iTrader: (1)

You could try shielding the cable. I bet it has a shield but when you cut the connectors and redid
them it may have been disabled. A shield can be made with foil or mesh and should surround the
cable from end to end and only be grounded on one end.

RX7TR7

Ill give it a shot. Another thing I noticed tonight sounds like the spark is arcing in the distributor cap, I heard a ticking sound coming from there. Also it seems the tach flutters most on deceleration. Also when I turn the electric fan on or off it flutters a lot. Do you think its just not grounded well?

t_g_farrell

iTrader: (1)

Run it at night and turn out all the lights. You may be able to see where the ticking
is coming from. Still sounds like a noise problem but if that cap is arcing that may
be the source of the noise.