General help needed, 12a carb.

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08-14-09, 12:51 PM

#26

Kentetsu

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Quote:

Originally Posted by TheRX7Project

I am ONLY running leading ignition. BOTH GM ignitors are hooked to one magnetic pickup (now the trailing), and I am using wasted spark.

There is NO WAY it is an ignitor- if that was the case, one of my rotors would get no spark. I am running direct fire- 1 ignitor and 1 coil per rotor.

There is no "leading" or "trailing" ignitor in my setup. I am running 2 ignitors, yes, but BOTH are for the leading plugs, one for each.

Can anyone else explain this better than I can?

You cannot run wasted spark on the trailing ignition. Your motor will go boom...

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08-14-09, 02:09 PM

#27

DivinDriver

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The pickup coils are molded in place on the pole pieces; no real way to move them from one position to the other without major surgery.

Did you re-time after switching your igntion to the trailing (~20* later) coil?

Have you verified that your advance mechanism for the trailing pickup is working smoothly?

Try checking resistance thru the pickup coils - - they should be roughly equivalent.

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08-14-09, 05:11 PM

#28

TheRX7Project

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Quote:

Originally Posted by Kentetsu

You cannot run wasted spark on the trailing ignition. Your motor will go boom...

I am not running my trailing plugs with wasted spark. I am running my leading plugs, with wasted spark, using the trailing magnetic pickup in the disty.

My mechanical advance is working properly, the vacuum advance is unplugged. I have not re-timed yet. Unfortunately, my main pulley does not have timing marks. I need to find TDC using the inspection plate and mark for TDC.

I looked up the air gap and it should be .020-.035... good guess!

I did crank the disty all the way to advance and it runs better, but still idles rough. I think I simply cannot get enough advance at idle using the trailing side of the distributor.