Hey guys, I recently installed a MSD coil in my 1985 Corvette with the digital dash, I come here because people aren't as active on Corvette forum as they are here when it comes to this stuff.

Anyway, when I installed the coil, if I revved the engine, the tach would not go higher than 2600 RPMs, but you could hear the engine revving higher than that. If I slowly brought it up passed 2600 RPMs, it would display the actual RPMs.

I called MSD and they told me to bypass the tach filter, so I did, now when I turned the car on the whole electronic dash cluster was flickering and it was impossible to read the RPM reading, or even anything else on the cluster. I'm going to install the tach filter again, but I was wondering, what can I do to fix this problem?

Thanks!

 

Did you try a MSD tach adapter? You could also try a 10K resistor in series with the tach wire.