Spark Plug ???
Thread Starter
Burning Brakes
Joined: Aug 2002
Posts: 830
Likes: 29
From: crestview fl
Spark Plug ???
Guys
I'm replacing my original 1969, 350 distributor to a HEI distributor along with a 35000 volt canister coil. Should I run my current ACDELCO R43S plugs or should I be running another plug that will operate better with the higher voltage coming from HEI setup and current 93 octan fuel? I recently purchased a complete TSP HEI setup (Distributor, coil and wires) just want the whole ignition system to work flawless.
thanks
Mike
I'm replacing my original 1969, 350 distributor to a HEI distributor along with a 35000 volt canister coil. Should I run my current ACDELCO R43S plugs or should I be running another plug that will operate better with the higher voltage coming from HEI setup and current 93 octan fuel? I recently purchased a complete TSP HEI setup (Distributor, coil and wires) just want the whole ignition system to work flawless.
thanks
Mike
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,137
Likes: 4,248
From: US-PNW
The gap change that calwldlife cited is the only real change needed.
The ACDELCO R43S is a pretty "cold" plug to be running unless you do a lot of high rpm highway driving. Better for all-around driving, is the R45S. It doesn't get loaded up with extended idling in traffic and general sub-60mph driving because the higher heat retained in the plug burns off combustion residue.
If you are replacing plugs and aren't married to the Delco name, check out NGK or Denso plugs. A lot of us here prefer them for their higher quality and reliability. NGK and Denso are ignition component manufacturers while AC Delco is just brand name.
The ACDELCO R43S is a pretty "cold" plug to be running unless you do a lot of high rpm highway driving. Better for all-around driving, is the R45S. It doesn't get loaded up with extended idling in traffic and general sub-60mph driving because the higher heat retained in the plug burns off combustion residue.
If you are replacing plugs and aren't married to the Delco name, check out NGK or Denso plugs. A lot of us here prefer them for their higher quality and reliability. NGK and Denso are ignition component manufacturers while AC Delco is just brand name.
Advanced
Joined: Oct 2024
Posts: 80
Likes: 22
From: Michigan
I agree with Owen that NGK and Denso plugs have higher quality, reliability, and consistency of all around performance. ACDelco is still a good plug and better than a lot of other plugs. Years ago when I raced, I ran an AutoLite plug that was used in taxi cabs. Never had an issue when everyone else was trying to clean out their Champion plugs after a flooded start.
Dave
Dave
