Hello,
I want to mount "Petronix Ignition" in my Cadillac 1955. I wonder if the distributor use positive or negative ground??
Please,any?
I cant answer your pos / neg question but I would strongly recommend taking timing readings with a timing light before you do the conversion. Many people have said that the timing changes by a couple of degrees after the conversion. If you take before readings it will then be easy to put it back to the original settings if it does not run right after the conversion.
I use the Pertronix system in my 1948 Cadillac. In my case it was a negative ground. Of course yours is a 12 volt system, but pretty sure it would be negative ground. Is your battery negative side wired to the frame or chassis of the car...? if yes..it is a negative ground.
And yes, I highly recommend resetting the timing, but this is not a result of the Pertronix unit per se....but more so the fact that you have to mess around with the distributor. Anytime you adjust, remove the points or distributor...it is always highly recommended that you re-check the timing.
BTW, I also use a Pertronix ignition system in a high performance 327 Chev and in the past in an Olds 455 Rocket engine. In my experience, they are by far better than any mechanical point system...and they maintain the original look of your engine bay.
Vic Brincat
Hello,
Many thanks.. Yes, the battery negative side is wired to the frame...
So, I have negative ground then....
I have used several of the Pertronix modules in old Cadillacs and been very happy. The main thing is to GET THE RIGHT ONE! They make 6v and 12v versions, positive and negative ground. So get the 12v, negative ground version for your 1955. I don't know the model number off-hand. The only time I have had any trouble is when someone inadvertantly sold me a 12v version for a 6v car (it didn't work worth a darn).
Right now I have these modules in my 1950 (6v) and 1956 (12v) Cadillacs. Very good performing units....