MTFCA Forum

I have read on the forum that many folks with distributors really like the performance with the ignitor plate installed. So I put one in (Pertronix), along with the recommended carbon plug wires. I followed directions to the letter and have very poor results (it runs very rough). I have a 12 volt coil that requires an external resistor. I tested the coil and have 1.6 ohms across the poles. I get 3.4 when I measure after the resistor (easily meets specs). I get 12.2 volts through the ignition wire that attaches to the resistor (good). I tried a jumper wire (per instructions) from battery to red igniter wire as a test - still runs rough (no difference). It is also well grounded. She does run and all cylinders are firing but very “erratic” – it was way smoother on points... The advance/retard lever has very little play – a slight move of the lever either way starts coughing…. Any comments on what to try next? I am stumped...

Your ignition set-up sounds correct! Check your spark plugs----good luck--Paul

Do you have a ground wire between the body of the distributor and the engine block? I found that even though the distributor housing is seated in a metal adapter plate that is fastened to the block, ignition was still somewhat less than optimum until a hooked up a separate ground wire. I didn't think it should be needed but it really helped. The Petronix unit may be more sensitive in that regard than your conventional point setup was. Simply moving the distributor might be affecting the ground as well if there is no external ground wire.

Thanks for the comments... Well, the plugs are good and run well with the points. I too suspected this could be the issue so tried gaps of .025, .030", and .032". To be honest I could not tell the difference... Just runs like crapola... I do have a dedicated ground from dist head to block per advice on this forum... I have tried everything I have found combing the forum... Stumped...

I had same issue a few years back. Even tried another Petronic unit to no avail. Went back to points, no missing. I have found that using a 12 volt system on one of the cars, a coil with internal resistor worked best. If you want to try one, go to local car parts store and ask for a coil for a 1967 VW beetle. The one on the Huckster has been in service for 11 years with no issue.
Tom

Are you sure the spark lever is advancing the timing properly ?
And are the wire posts/rotor still lined up when the spark occurs ?