Bought a set of original Rally Pack to my 70 442 that didn't come with them. After reconfiguring the wiring, everything seems to work, but the tach reads about 500 rpm too low. In fact at idle it is barely moving. I wouldn't think the converted HEI would be the culprit, but don't know. Any suggestions?

 

I have a 1970 RALLYE 350 with a rally pack, It had an HEI in it when I bought the car, my tach at idle has a problem to, it reads about 6-7,000 rpm at idle, I have been told to send it off to have something changed inside the tach to work with HEI! Brian

 

It should work fine with an HEI, double check your connections. I'm not sure about calibrating it.

 

The TACH terminal on the HEI provides exactly the same signal to the tach as a normal coil connection on a points-style ignition. There should be no issue with the HEI.

 

There must be something wrong inside the tach! I plan to send it off at some point and have it gone though! Brian