1988 V30 Tach

[Scottycutlass]

I got an 88 V30 454 carburated. I have a factory tach I found and want to hook up. On the HEA cap there is a yellow wire plugged into the tach port. Where does this wire go and what might it serve. It looks factory because it is built onto a double plug in with the power wire.

 

[da_raabi]

Computer maybe?

 

[Scottycutlass]

it looks like it goes to the emissions control, but i do not have tbi or an electronic card. Could I use an Autometer tach adapter?

How does a factory tach signal work?

I see lots of people wanting to install tacks on 1987 to 1991 square bodies but it seems like every forum gets high jacked by some other topic.

 

[RetroC10Sport]

Is it a an original carb truck? I know a few were made. The VIN will have a W in the 8th digit.

There is an engine speed switch which controls the A.I.R. diverter if equipped with A.I.R. and that will have a wire going to the tach terminal.

Either way, the adapter should be fine if you want to go that route. I doubt just piggy-backing the wire that's there will hurt anything either.

 

[Scottycutlass]

Thanks for the information.

It is an original cab truck with the W code you pointed out. I found it in Rochester NY. It has been sitting untouched in a heated garage since 1992 with only 31000 miles. Its also a Silverado packaged truck with all the power options and 4 speed. They bought it for their tow business and started to paint it blue to match there fleet and never finished it. It will be red as it once was and I installed a hoist and will be placing an aluminum flat bed on it.