bl98GT

I recently purchased a aftermarket tach for my stang, it uses a spark plug wire induction clap for the RPM signal. After installing I noticed the the RPM's did not read correctly until the engine had reached 1500 RPM's. I sent a email to the company explaining my problem and this is what they replied with:

"Your mustang uses the multi-strike ignition where the spark plug fires more than once below the 1500 RPM range. That is why the tach will work fine above 1500RPM. We do not make a tach that will work on your vehicle with that type of ignition."

I have a 1998 GT, please tell me if this "tech support" guy is correct or just telling me something to shut me up!

Thanks in advance

kamelyn

unfortunately he's right, since our cars use the ignition coil packs the voltage(signal) actually increases with RPMs. If our cars had come with a single distributor then the voltage(signal) could be read easier, the tach works off of differences in voltage and amps going to the spark plug wires.

In my opinion the only thing the additional tach will help you with is shifting points other than that, 9 times out of 10 if you dont secure the wire clap correctly your will recieve incorrect reading on your tach.

Triisomy21

Why the need for an aftermarket tach? Did your car not come with one?

StangChik

i have a tach, just because it ws free, and i wanted the shift light, for bracket racing

DaMach04

you could take the shift light off of the tach and just use the light...

StangChik

i would defiantely do that, but i don't know how to wire it to my factory tach....