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Topic: Post-Swap Tach issues (Read 1392 times) previous topic - next topic

Post-Swap Tach issues

I'm new to not just this thread, but Thunderbirds as well, but I just purchased a 1983 Turbo coup from my uncle...

However he had decided that the standard turbo 4 wasn't enough, and did his own engine swap. From what I understand, here's how the car is as it sits in my driveway:

-original 1983 body
-V8 302 out of his friend's 1988 Mustang (wrecked the body but the engine survived)
 --That engine was supposed to have EFI but he couldn't figure that out so he put a carburetor on it.
- he never adjusted the in-dash tach so he put in a Summit tach next the shifter (pictured)
X

Now, since the car was originally spec'd for the turbo 4, the tach in the dash reads double, so I'm constantly looking at redlining it, or I have to go out of my way to look at the Summit tach. Is there any way that I can recalibrate the tach in the dash, or is it set and the only option is replacement instead of adjustment?

Post-Swap Tach issues

Reply #1
Quote from: Longhorn;464394
Now, since the car was originally spec'd for the turbo 4, the tach in the dash reads double, so I'm constantly looking at redlining it, or I have to go out of my way to look at the Summit tach. Is there any way that I can recalibrate the tach in the dash, or is it set and the only option is replacement instead of adjustment?
AFAIK only the '87 & '88 tachs are easily recalibrated, that requires disassembly and replacement of a resistor inside... There were no buttstuffog V8 tach options for the early models, cluster is totally different than '85-'88...

Post-Swap Tach issues

Reply #2
That's what I was afraid of; anything I could find about recalibration was for those years.
Although since the speedometer is also off (any time I'm going under 35mph it bounces +/-10mph), that makes most of that dash cluster inaccurate, I might just take it out and use it as a template to build a fresh one out of aftermarket gauges. It might not be pretty, but it's had enough other atrocities committed to it there's no hope of it being brought to factory spec/show car status anyway.

Post-Swap Tach issues

Reply #3
Speedo jump is usually solved with a new speedo cable.  Mine did this a couple of times over its life and that was always the solution.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

 

Post-Swap Tach issues

Reply #4
Quote from: Aerocoupe;464400
Speedo jump is usually solved with a new speedo cable.  Mine did this a couple of times over its life and that was always the solution.

Used to be a common fix for jittery speedo, pull core out of cable, lube and reinstall...