Called msd today about a tach. problem an two words THEY SUCK cant get a straight answer from no one I called numerous times!!!!!!!!!!!!!!!!!!

 

I love MSD's product range, but I do agree their tech service could use some work.

 

That's for sure my tach doesn't work an told me buy 64$ 8920 tach adpter an now im stick with it an tach still doesn't work .

 

and your sure your tach works (just asking)
what make is it? (the tach)

 

Yes it works I had 2 an they both worked now im using a msd6al box an pro bill. dist an coil it doesn't work even with the wire direct from the cluster to the box msd said a 8920 adapter for 64$ still nothing. wire is white from tach. any suggestions please.

 

Not sure what your setup is exactly but here is how I wired my 6A and billet distributor on my 84 TA. I am using the 8910 vs the 8920. I also found a 10K resistor inline with the tach wire had the tach working about 90%.

 

like above.. look for what the closest wire set up to what your running.
it's simple..just need to work it out..

check grnd
check power
most of the time its the small things that get ya..