1970 cortina GT wrote:Old, topic but I have another question. Once I have converted my tacho to negative earth is there anything else I need to do to it if I'm using a Petronix electronic ignition? There is a place in NY called Nisonger that suggests there are some other changes necessary? They are looking at $275 US to do the conversion, appreciate your thoughts anyone. BTW I ran an Accuspark electronic ignition in my MK2 and whilst it is negative earth I didn't change anything else in the tacho.
I (vaguely) remember doing the conversion on a '66 Elan as well as a couple of Lotus Cortinas, both '65s and don't remember doing anything with the rev counters to get them to work properly - and I drove using the rev counter back in those days, rarely looked at the speedo!
Thanks guys, I've seen the positive to negative ground conversion details it's just the electronic ignition installation and associated possible changes to the tach that I was wondering about. Thanks.
Life isn't complete until you have a pair of twin cams in the garage...
1970 cortina GT wrote:Thanks guys, I've seen the positive to negative ground conversion details it's just the electronic ignition installation and associated possible changes to the tach that I was wondering about. Thanks.
Small correction to my previous post, I did have an rev counter issue with a Plus 2 did I did the conversion on but that had an early MSD...I think the information to allow an easy (cheap) conversion is out there, just a question of finding it.
Electronic ignition won't effect the operation of tach after converting the tach to -grd.
If using MSD you will need to install a tach adapter ( made by MSD Inc. ).