Thread: Electronic Ignition & Spark Plugs

Hello All,

When a Holden points ignition system is upgraded to an electronic system do the spark plugs need to be upgraded too?

I fitted a new Bosch clone electronic Ignition to my early HQ 202 cubic inch red motor. The electronic ignition distributor came with a new genuine Bosch coil and new spark leads. Plus a not more than postage stamp sized instruction page. It was a pretty comprehensive kit. However, the instructions did not mention anything about spark plugs or spark gaps.

I took one of the old spark plugs out and I went to an auto-parts store where I bought a new set of the same plugs.

Should I have bought a different specification set of plugs, and if so what ones?

Also, what size gap setting should there be for the electronic system?

Kind Regards
Lionel

Holden HEI distributors were designed to run plug gaps of up to 0.060" (1.5mm) so they could run extra lean mixtures. However it is quite unnecessary for a normally tuned engine to run these gaps. Anything around 0.032" to 0.040" (0.8 to 1.0mm) is adequate for full performance. Larger gaps tended to burn out the leads after a couple of years of normal service.