Dialing in an aftermarket tacho....

[jono]

I recently discovered after an engine swap that my tacho was reading a bit too high. The 1400 idle did not sound or feel like 1400 and the power coming on at 6000rpm was pretty wicked up to 8000rpm

 

A chat with one of the company's tech guys explained there can be a few factors to cause a tacho to tell fibs.

 

I was told an inline resistor between coil and tacho may fix it, so I hooked up my little resistor wheel to the tacho and mounted up my old L Series tacho to the dash top on its own as I had pulled it from the gauge set.

 

Took it for a run, and sat about revving it like a tosser a and in no time at all my after market tacho was calibrated to match the ea82 tacho with a 6800 Ohm resistor inline

 

Never heard of this process before but was pretty simple to resolve. And cheap, like was it eight resistors I had to buy for total cost of 55 cents!