right, im using 1.0 12v clocks (electronic) and ive tried both an F20 transponder and one of a 1.2 8v Nova, and none of them appear to be working correctly

would the problem be because the clocks are the standard 1.0 12v ones?? what would be the best solution?? trying new clocks??

the transponder is wrong, the one from the 12v has a different pulse frequency to the F20 one, using the F20 one should cure it

at the moment the speedo is getting 3 pulses for every 4 it needs, so its getting confused

I assuming you using electronic clocks? Should be using the F20 sender now not the one off the old box?

ive recently replaced my 1.0 12v, for a C20XE on carbs, problem i have now, my speedo reads wrong. when doing say 60mph, the speedo reads about 25mph at the most

anyone had this same problem?? or knows what causes it??