I just installed a 6A in my '89 gta. She seems to run fine, but the tach is sluggish on the way up when I floor it.

What could the problem be?

Is there anything I could have done in the wiring to cause this?

 

dp u feel any diff from it is it any good i am getting one and seen ur post so i thought i would ask thanks

 

It idles a little smoother, and spins the tires a little quicker. But other than that I don't expect to feel much of a difference until I do a complete tune up.

Can anyone answer my question?

 

The GTA's normally require a tach adapter part number 8910 if it does not function. Just to be safe check with in about 1-2 feet of the coil on the white wires and see if there is a roughly 1 inch square with a white going in one side and come out the other. It will also have a black ground wire. By pass this filter if it is there and the tach will work correctly. If it is not there you will need the 8910 adapter.

Thanks,

Joe
MSD tech

 

The tach DOES function, however it is sluggish at times. I'll check for that filter later on today. Thanks!

 

I ran the adapter with mine, i noticed instant better startup, and revs, the idle seem to be smoother also....

 

I also have the 6A on my 88 TPI. After it was installed, I noticed that the Tach did NOT work the way it used to. I ended up cutting the tach wire at the coil connector, and running a wire to the tach output on the MSD box. Worked like a charm.

I noticed: easier starting, better throttle response, slightly increased fuel economy, but, not much more horsepower.

 

I have a 6A. I also ended up having to run the adapter mentioned above. I had problems with it being sluggish and acting generally wierd while it was fed from the negative terminal of the coil so I moved it to the tach feed on the 6A itself. That didn't work either as the tach would go to 0 around 5200 rpm. The tach now works perfectly with the adapter installed. See my comments in the updates section of my site for more details on my trials with the 6A.....

 

Which is the tach wire that I should run directly to the MSD box? And where is best to cut it?

 

I might have the same problem with my setup.
86 Trans Am, 87 TPI, 91 ECM, MSD 6A, Blaster 3 Coil.

Tach seemed like it was revving up slow, I wasn't sure if it was because I hadn't seen my tach move in 8 months when I tore the motor apart. I don't remember how fast it was supposed to move. Running open headers is giving me a head ache.