Speedometers and Tachometers 1974-1976
 

I'm looking for a info on speedo's and tach's. What year cars had what speedo's and tach's in them? Did the engine size dictate that or the trim level of the car? Would a 350 Formula have the same set up as a Esprit or a 455 Formula? All TA's 160/8K? I'm interested in the 70-78 years at the moment. I'll post this question in the 70-73 forum as well. Thanks

'75 T/A is 100 MPH with 8K tach

1970-74 160MPH/8K tach 1970-73 250 temp gauge

1975-76 100MPH/8K tach

1977-79 100MPH/6K tach

My 1976 "plain Jane" Firebird has a 100- mph speedometer and a 5,250 yellow line and a 5,600-rpm red line. It was a 350 2 bbl. car originally. It was ordered with a tach and gauges.

My ‘76 T/A came with a 6k tach and 100 MPH speedo. The speedo is fun because the numbers stop at 100 but the hand will keep going around the circle 😁

I am not professing to be an expert, but I believe this needs a slight amendment;
(mention of temp removed since the query was just about tachs and speedos)

1970-1972.5 160MPH "brake" light at bottom of speedo / 8K tach
1972.5-1974 160MPH "brake" & "belts" lights at bottom of speedo / 8K tach
1975-1976 100MPH (KPH in blue as secondary) / 8K tach
1977-1978 100MPH (KPH in blue as secondary) / 6K tach
1979 100MPH (KPH in orange) / 6K tach w/"QUARTZ" above clock
1980-1981 85MPH (KPH in orange) 6k tach

The 1970-1974 speedos look the same (the seat belt minder seperates the two);
The 1975-1977 speedos ARE the same;
The 1979 speedo is a one year part;
1979 & 1980-1981 speedo is "USA" MPH-dominant or "export" KPH-dominant;
The 1970-1976 tachs all look the same;
The 1977-1979 tachs look like the earlier tachs (but with different redline and number spacing);
The 1980-1981 gauges are different in appearance and have several unique traits compared to earlier gauges.

I assume you bought this brand new? If so, it had to been a very late '76. I have never heard any '76 come with a 6k tach.

ditto.

I have only seen bad sources citing the 6k tach was introduced 1975 or 1976 (depending on source).

According to the GM Parts Catalog, the 76 T/A had the 6k tach (part no. 5659065). The 76, 77, and 78 all had the same tach.

I would chalk that up to an error, or possibly a later version where the 6k rpm tach was for some odd reason deemed as the superceded part;
I'd guess the former before the latter.

I strained my eyes as much as I dare against that tiny image;
But to back up my assertion of it being either of those suggested scenarios, that appears to be a somewhat generic parts book from 1987 - over a decade after the 1976 cars were built.

Both of my 1967-1976 Firebird MPC's do not show that part number.
My 1985 printing of the "1977-1981 Pontiac" MPC shows that number as 1977 & 1978, but also gives a different part number for a revised tach used for 1978-1979.

But pulling our heads out from behind books for a moment, there is the overwelming first hand accounts of what people had..
Then there's the accounts of parts people pulled from purported unmolested cars. I have personally been around, pulled parts from, or worked on a good number of 1976 TA's, and they all had 8k rpm tachs.

Please consider adding all of this as well as the previously held general consensus (that the tach rpm limit change being for the 1977 model year) into account.

Interesting. The image I posted was a page from the official Pontiac Parts Catalog, published by GM. Maybe these copies will display larger. In your version of the 67-76 parts catalog, does it have the 70-76 MYs grouped together with the same part number (for the 8k tach)?

I can’t speak to your experience, just that the 76 T/A I own has a 6k tach and the parts book specifies a 6k tach for that MY.

I've seen a lot of '76's and ALL had the 8k tach. One of the Smokey and the Bandit movie cars, which were all 1976 T/A's with the front nose and hood swapped for 1977 parts had the 8k tach. I'm assuming that they were late builds since the movie was shot 8/76-10/76.

https://forums.maxperformanceinc.com...4&d=1496074099

According to the June, 1977 parts book, BOTH the 5659050 AND 5658075 tachs were specified for use in the 1976 model year.

https://forums.maxperformanceinc.com...1&d=1642249166

https://i.ebayimg.com/images/g/pn4AA...VE/s-l1600.jpg

https://i.ebayimg.com/images/g/apcAA...TY/s-l1600.jpg

The 5659050 and 5659065 were discontinued by GM in 12/90.

https://forums.maxperformanceinc.com...1&d=1642249589

My "plain Jane" 350 2 bbl. car I mentioned earlier does have an 8,000-rpm tach.

So 1976 was a something of an overlap year with both the 8k and the 6k tach. Glad we got to the bottom of it. That 1977 parts books seems to indicate that the 6k tach was the tach for the rally gauge package that year.

80 was also a overlap year. My October 79 built. 1980 SE W72 WS6 car has a 100MPH speedo with the old font but has the 3 lights in the bottom for the seat belt, brake and check engine light like allot of the 80 models.

Can post the build date of your car to help pinpoint a possible switchover date for when they started using the 6K in 76 Firebirds.

the gauges would have changed with the model year - the only second generation Firebird exception is the mid-1972 introduction of the seat belt warning.

I have learned from people much more knowledgable than myself that the MPC’s sometimes have errors, and other times the stated year should not be taken literally instead of model year, it implies calendar year.

I’d wager that second “76” listing is the ‘77 part.

FYI;
That NOS 8k rpm tach;
It has a stamped manufacture date of May 17, 1976;
It is my understanding that this was just before the change over to production of 1977 model year parts.
If the tach changed over before the end of the 1976 model year, wouldn’t there be more evidence to support this?

Sometimes even in spite of proof is given, people won’t adhere to reason - they instead continue to see things they way they want to interpret it.

My 76 with a 6K tach was built the first week of September 1975.

I was expecting a late date, not a super early one. Any chance it was changed at some point?

i don’t believe that for one second.

i’d wager that if the gauges are pulled out, the tach will have a post-1976 assembly date.