Petronix vs 123

I’m rebuilding a 4.2 for my mk2. I have the stock distributor, but I don’t like dealing with points and I’m not concerned with keeping the car original, but would prefer a distributor look over EDIS. I am seriously considering a Jenvey conversion after I get everything dialed in. I am not planning on racing it, but some performance would be nice.

Thoughts & experience on 123 distributor ($500-600) vs. Petronix distributor ($300-400) vs. Petronix kit in a stock housing ($150)?
I’ve used the Petronix kit in a Chevy before and it offered great, trouble-free performance. It’s a lot cheaper than a complete drop-in distributor.

the petronix kit works well and is reliable however it depends on the condition of the distributor. if you are chasing performance and idle quality etc etc then I would lean towards the 123 distributor. I have not had any experience with the pertronix distributor.
Just MHO

I put a Jaguar-6-R-V 123 distributor in my 1967 420 with the 4.2 and while it was a HUGE improvement, it’s not exactly a fair comparison as I believe the old distributor was pretty tired. I do like the ability to easily select different advance curves and the fact that it turns itself off after 1 second if the engine isn’t on is a huge advantage over some of the Petronix modules I have used.
The only problem I had was that the 123 distributor shaft was slightly too large to fit in the block and I had to lightly dress it with some emery cloth to get it to fit.


For what is worth: Petronix will work fine in the stock housing. It’s a direct replacement.

I have experience with both (for what is worth). At present I use 123 with the bluetooth module.

This allows real time monitoring of your advance, proper programming and various set curves for when you need to use ethanol -which happens here in Europe-. The phone interface is great, easy to use and has even a digital immobiliser.

In case you do not need all that, then Petronix kit is fine and reliable.



I had Pertronix installed on my 1967 Mark 2 3.4 21 years ago and it has performed flawlessly since that time.

Mel R