GM LS2 Trigger Pins

Replacement Ignition for Tecumseh HH100 thru OH180 and others. Uses GM LS2 Ignition Coil and a modified GM PC2 Crank Sensor. Has three levels of spark advance: no Spark, TDC spark and Advanced Spark for easy starting.

[@johntomblingson7451]

After watching this I am going to use a gy6 ignition cdi and coil with a axle speed sensor for the trigger. Trying to bring a OH 180 back to life. Thank you for the information about the pins.

[@jimnelson7740]

On my HH120, with the original pins, I had to set my TDC pin at .054". That left the advance pin not kicking in at idle, but very shortly after coming off idle. Seems to work fine that way. I'm using an LS3 module, and PC2 sensor from a 92 Buick with a 2.3 liter engine.

[@melvinsmutters7662]

I genuinely enjoy this. I'm experimenting with an hh100. I'm also curious about high frequency interference from a standard 12v canister coil and an hei module. timing

[@rexhavoc2982]

What RPM must the starter motor spin the engine to make spark ? Show me a wiring diagram that will work for rep-lacing the stock coil. Thanks.

[@melvinsmutters7662]

I'm also curious how the ignition advance actually works. Wouldn't the pick up trigger Fire the coil twice once at TDC from the tall pin and again at the short pin say 20 deg before TDC?

[@jimnelson7740]

I think it would, but so quickly after main ignition, it would have no effect.

[@garryludwick2990]

I installed a HEI, pickup and coil. I get good spark BUT excessive backfire . I'm starting it down to check the valves,OH120. I have 50PSI and it fires
I'll check the pin/key locationand make sure it is TDC. You have me wondering if I have an issue

[@jimnelson7740]

I saw a video where the guy said the GM HEI module can't keep up with the pulse rate above 2500rpm, and that's what causes the backfiring. He mentioned switching to an Excel, or Accel module to solve that.

[@garryludwick2990]

Thank you soooo much. I was getting ready to ditch the key and set the flywheel by hand. I'll try that first👍

[@jimnelson7740]

@@garryludwick2990 I'm not an expert, Garry. Keep that in mind...LOL I'm still trying to figure out why the GM module can't keep up. Lots of engines rev much higher. Maybe the double trigger is causing that....convincing the module the revs are twice what they are.

[@waynew2831]

I watched the entire video, more than once. I am still confused. EXACTLY WHAT do the trigger pins do? They apparently are not magnetic. Is GM LS2 simply a proximity switch, that fires the coil, as points would. Please explain if you can. Thank You

[@jimnelson7740]

That is a very good question, and one I asked myself after watching the video. The pins are magnetic with the original solid state ignition.

[@tesla747]

The pickup reads the magnetic pins and sends a trigger to the ignition controller and fires the spark. He is checking timing seeing if he needs to move the pickup left or right.