differences between tach and econo gauge clusters

by 1973 454 MONTE on Thu Dec 08, 2011 6:47 pm

73 tach front

76 econo front

73 tach back

76 econo back

by lagunainnewark on Thu Dec 08, 2011 7:25 pm

I changed my 76 Laguna over to a tach, If I remember correctly, I added a inserts for the tach and ran the wire to the distributor. I can check the prints and my spares If you need, Ron.

by Mcarlo77 on Thu Dec 08, 2011 9:40 pm

From what I could see on the '75 Laguna w/tach in the salvage yard vs the '76 Laguna w/Economy gauge, the underhood wiring harness from the junction block on the firewall is the same. The required tach wire, though, runs through the firewall along with the wiring for the A/C-Heater harness. What I'm unclear about is whether this tach wire, which appears to be bundled up inside the main underdash harness, runs to the back of the tach...or, runs into the muti-wire connector behind the speedo? In short, can you utilize the same underdash harness (as with the Econo gauge) and just add the tach wire out to the distributor?

by 77mali on Fri Dec 09, 2011 7:34 am

The only diff I see is the vacuum port on the rear of the pod for the economy gauge. I think the tach has to connect to the HEI as well as somewhere on the fuse box. Wonder if the box has a dedicated slot for "Tach"? I have a 73 monte harness but my cluster is the large gas gauge w/ speedo but I'll look to see if there is one on non-equipped anyway.

by 1973 454 MONTE on Fri Dec 09, 2011 4:29 pm

77mali wrote:The only diff I see is the vacuum port on the rear of the pod for the economy gauge. I think the tach has to connect to the HEI as well as somewhere on the fuse box. Wonder if the box has a dedicated slot for "Tach"? I have a 73 monte harness but my cluster is the large gas gauge w/ speedo but I'll look to see if there is one on non-equipped anyway.

by lagunainnewark on Fri Dec 09, 2011 4:45 pm

The power and grounds are already in the circuit board, add the tach wire to the main connector then to the distributor. You can trace the track lines on the circuit board to find the correct pin position. Let me know if you need more info, Ron

by Mcarlo77 on Sat Dec 10, 2011 12:24 am

That's what I wanted to know, Ron...thanks for the pics and info!

by lagunainnewark on Sat Dec 10, 2011 10:35 am

No problem, anything to help. Ron

by 77mali on Sat Dec 10, 2011 10:43 am

1973 454 MONTE wrote:
77mali wrote:The only diff I see is the vacuum port on the rear of the pod for the economy gauge. I think the tach has to connect to the HEI as well as somewhere on the fuse box. Wonder if the box has a dedicated slot for "Tach"? I have a 73 monte harness but my cluster is the large gas gauge w/ speedo but I'll look to see if there is one on non-equipped anyway.

I see why now, the 73 has an amp gauge and the other a voltage gauge. Very curious thing.

by lagunainnewark on Sun Dec 11, 2011 9:57 am

GM made the same change in the trucks also. From personal experience, I've seen the dash melt from the current through the amp gauge. I also think they did it to save $$$. Ron

differences between tach and econo gauge clusters

differences between tach and econo gauge clusters

Re: differences between tach and econo gauge clusters

Re: differences between tach and econo gauge clusters

Re: differences between tach and econo gauge clusters

Re: differences between tach and econo gauge clusters

Re: differences between tach and econo gauge clusters

Re: differences between tach and econo gauge clusters

Re: differences between tach and econo gauge clusters

Re: differences between tach and econo gauge clusters

Re: differences between tach and econo gauge clusters