Hi all...

I just recently replaced my CraneCam Fireball HI-6S with a HI-6 box. Now, my stock tach acts nuts when it's above 3200 RPMs. The instructions with the HI-6 states the GM's have something called a TACH FILTER that needs to be disconnected and then the tach is plugged directly into the TACH line on the HI-6.

Does anybody know where in the heck this filter is?

Thanks,
Mike

 

Doesnt exist.

MSD sells a tach converter or something that allows their box to be used and not screw up the tach on cars like yours and mine. Crane should have something similar.

 

I thought you were talking about my new carb belt, or some blinker fluid.

 

Naw, actually talking about your muffler bearing.:lala: :lala:

 

Thanks... I'll see what I can find!

 

I just looked in the instruction sheet that came with the HI-6 unit. It says there are two different type of tach adapters. It all depends on if it's picking up the tach single from the pos(+) side of the coil or the neg(-) side. I'm GUESSING that on our cars, it's pulling from the neg(-) side of the coil (like most other cars do). To verify this, I looked up the wiring diagram in my Chiltons manual, BUT is doesn't state if it's (+) or (-).

Anybody know?

It's not that bad, the tach is still functional upto 3200 RPMs, after that, forget it!!

Thanks....

Later,
Mike

 

Isn't the tach filter built into the harness?

 

Dont know if it doesnt exist on later models but my 83 TA had one right behine the distibutor , clipped to the firewall.

 

the take wire is on the negitive side its normally a white wire