caged02

iTrader: (21)

I did a 2001 LS1 swap in my 1956 Bel Air and I am doing an old school look to this car and wanting to run a Sun tachometer from the late 60's in it. I am running a stock 01 computer and have the green wire off of the tach connected to #10 pin white wire that is the tach lead off of the computer. It wont read at all, I have tried a resistor in line and that did nothing either. I either have a bad tach or ?? Please if someone has done anything like this let me know if I am missing something. Thanks.

5.3LJimmy

iTrader: (10)

It sounds like you may have a bad tach. I'm not familiar with the 60's version, but I would imagine hookup is the same: black = ground, red = hot, green = signal, and white = illumination. Can you set the tach for 4, 6, or 8 cylinder applications? The signal wire from the PCM requires that the tach be set for a 4 cylinder to be properly calibrated. Even if it's not you should be getting something, it just will not be accurate.

Jaysz28

iTrader: (19)

I doubt the tach is bad, you just need to build a pull up circuit like I did

https://ls1tech.com/forums/conversio...l-no-tach.html

Good luck with it

-jason