mk1-forum.net

Most of the "old" tachometers are current driven, when you fit "electronic contact breakers" the current isn't enough anymore to drive the tacho. That's why you end up with more spark!

The thing to do is convert your tacho from current to frequency driven.
You can do it yourself (if you have the skills) like this way;
http://www.dinoplex.org/tachoconversion/

Or buy an "add on box" like this;
https://www.spiyda.com/magento/index.ph ... board.html

i have just fitted one of the conversion kits from spiyda. to my tacho

it came will packed, good instruction, great website with YouTube videos, so easy to follow.

i have calibrated it , and everything is now set right, but still not tested it on the car, but i can't see that being a problem.

he was also easy to contact and replied to his emails quickly.

great if you want an old 60/70 smiths tacho but run electronic ignition.