DYNO RUN / IGNITION

[SillyRB]

Well took it back to the dyno yesterday.Fixed the fuel pressure problem, The car is holding Fuel Pressure beautifully. With the hose off @ 41 psi (Static). So the first pull the car made 440 HP and 379 TQ, this is on a Mustang Dyno (F-Y-I) Reads lower than a Dynojet pending calibration. Anyway, after that we let it cool down, we change the plugs, the A/F on that pull was a 11.2-11.7. Steady. Than the car starts missing ? Everytime after that, anything more than 18 psi or so, the car started missing. Checked the plugs --> They were fine. Checked the ground for the microtech --> Fine. We messed with the spark on the microtech, put it low, and high and still mis-fired.What else could it be ? I am still using stock OEM Coils, could it be that they are getting to hot and are not able to carry the spark ? What else could it be ?? Should i try an aftermarkey coil , CAS ?? What are stock coils good for, Please all suggestions are welcome.

So i lowered the boost down to 14-15 psi and just drove home, dont get me wrong, even on that boost level the car feels strong. +1 for the M/T Drag Radials on 14-15 psi those things hook.

[Carl H]

sounds like the higher boost is blowing out spark, try gapping all plugs to .8mm and see if that helps/fixes the problem.

[SillyRB]

So talked to Mack, he told to me to go with a Ignition Amplifier such as a EX Engineering Power Pack which is set @ 20 volts. or a Kenne Bell Boost a Spark which is adjustable from 13.5 - 20 walts. Any other ideas ?

[Wulfgang]

Bottom line is that you changed the plugs and it started missing. I know you said you checked the plugs, but I'd switch them again and see if that fixes it first. Then look at everything else you moved when you changed the plugs (coils, the wires, and ignitor).

I would not use a 20 V booster for the ignitor. As we have all heard, those coils already run really hot, and using 20 V to increase the current will only make them hotter.

Again, I recommend playing with the plugs. Try a new set of coppers first. If a new set of copper plugs does not work, then you might try some iridiums since they will fire reliably under almost all conditions (don't even dream about gapping iridiums though).

[SillyRB]

Bottom line is that you changed the plugs and it started missing. I know you said you checked the plugs, but I'd switch them again and see if that fixes it first. Then look at everything else you moved when you changed the plugs (coils, the wires, and ignitor).

I would not use a 20 V booster for the ignitor. As we have all heard, those coils already run really hot, and using 20 V to increase the current will only make them hotter.

Again, I recommend playing with the plugs. Try a new set of coppers first. If a new set of copper plugs does not work, then you might try some iridiums since they will fire reliably under almost all conditions (don't even dream about gapping iridiums though).

Well i did that while on the dyno. I put the other plugs in and it still missed. Then i put the other plugs back in and it sill missed. Could it be that the coils cannot handle the heat. I used Iridium Plugs , NGK's Heat Range of 8, .05mm. I have a series II RB25 with the microtech. I have no igniter chip per say. What other options ? The Kenne Bell Boost a spark has a variation for the spark which is adjustable ranging from 13.5 watts --> 20.

[Wulfgang]

Ah, I missed the part about the Microtech. What is that? Piggy-back or complete EMS?

[SillyRB]

Ah, I missed the part about the Microtech. What is that? Piggy-back or complete EMS?

Yes its a full EMS

http://microtechusa.com/computers.html

I have a LT-12

[FAST-DATSUN]

WE are using the XS box on all our drift cars in D1 and Formula d with no problems......Mack

[SillyRB]

WE are using the XS box on all our drift cars in D1 and Formula d with no problems......Mack

Did you guys ever have a problem before using the xs box. The box runs at 20 watts does that ever cause it the coils to run too hot. How kind of boost are you guys running.