[GREGGDOG]

Looking for a 70-71? Tach or Rally gauge set/cluster. Not sure if other year tachs are compatible as I'm running an HEI distributor.
Thanks much

[unruhjonny]

You're going to probably want a 1972-1976 tach;
If my memory serves me, they look identical once installed to the 1970-1971 tachs but have a third plug on the back for getting signal from the Unitized/HEI distributors.

I can take some pictures for you if that might help you source one.

These are actually reproduced, and the ones I have seen looked great.

Just a quick note about the repops, from what I recall all the catalogs have the tach's incorrectly listed;

• They were 8k rpm tachs through to 1976
• The tachs changed to 6k rpm units that looked otherwise identical to the 70-76 tachs for 77-78
• The 1979 tach is a one year tach, it looks nearly identical to the 77-78 tach except for the "QUARTZ" callout for the clock
• The 80/81 tachs are still 6k rpm/quartz unit, but have a different style printed face

[GREGGDOG]

Appreciate the post - yep forgot about the 72-76' HEI tachs. Will post 72-76 tach wanted. I'm leery of OER but may have to try one.
Would I have to change the printed circuit board from my 70,' or will 70' printed circuit board work on a 72-76, or OER? Thanks

[Mr. G]

Pretty sure I have a 76 or there about cluster but not sure if tach works or not.

[unruhjonny]

you will not need to change the circuit board.

That is a 1970-1971 specific part anyway.

The circuit board is only used to provide power for the clock, and provide lighting anyway.

['ol Pinion head]

The printed circuit on an early 2nd Gen T/A guage sets changed in mid Dec of '72 when seatbelt warning lights were added to all production guage clusters.

Both points & unitized ignitions were used on '72-74 model Pontiac V8's.
Electronic ignition (HEI) while avail on a few 74 model Pontiac V8's, became std on '75 models. Years ago, when I was out cleaning boneyards every week, the 8k tach & rally clusters were easiest to find out of '76 model T/A's. Pontiac simply made more of them & many more had been thrashed. Nice coloring of the tach face as well as being a functional tach typically went hand in hand but I have had a few nice late 8K tachs that were dead, & had to be rebuilt.

Mention the points vs electronic ignition issue as on numerous '70-72 projects have sent off original tachs from original points style ignition cars for rebuild & conversion to be suitable with electronic ignition. Not doing that on my '71's, retaining original points distributors.

[Formulabruce]

I run stock 1970 cluster/tach with an HEI.
Upgraded to a correct "Pink" wire from fuse box to the HEI.
TACH is accurate and works fine. Using a early 71 Formula harness.