Speedo wrong
Thread Starter
Cruising
Joined: Apr 2004
Posts: 12
Likes: 0
From: Lynnwood WA
Speedo wrong
Hi All,
I'm new to the Vette community. I just got a 91 Coupe, 6speed and I'm working through some of the issues it has to get it road worthy. It apparently has a new speed sensor but the speedo is way off. I haven't done any extensive testing but it appears to be off by 10 to 20mph (low). The car was originally an automatic. I'm not sure that this is important but I thought I'd mention it just in case. Can anyone give me a clue on what to look for in diagnosing the problem?
Thanks in advance,
Dave
I'm new to the Vette community. I just got a 91 Coupe, 6speed and I'm working through some of the issues it has to get it road worthy. It apparently has a new speed sensor but the speedo is way off. I haven't done any extensive testing but it appears to be off by 10 to 20mph (low). The car was originally an automatic. I'm not sure that this is important but I thought I'd mention it just in case. Can anyone give me a clue on what to look for in diagnosing the problem?
Thanks in advance,
Dave
Thread Starter
Cruising
Joined: Apr 2004
Posts: 12
Likes: 0
From: Lynnwood WA
Re: Speedo wrong (CFI-EFI)
That sounds plausable. Can you be more specific? I thought that these cars used a speed sensor that runs off of the front wheel for the speedo. Where would be gear you're refering to be? I've got a chiltons manual but it's basically useless.....
Dave.
Dave.
Burning Brakes
Joined: Nov 2000
Posts: 1,012
Likes: 1
From: Bowie MD
Re: Speedo wrong (davber)
The speedometer is NOT run off a wheel sensor. It is run off a set of small plastic gears in the transmission. The Automatics have a different rear gear usually something like 2.59 or the performance (like I got is 3.07). The 6 speed trans usually has around 3.45 rear gears. Then the rear tires also make a difference too. You should have 275-17 inch tires stock. Check those as well. You can have a transmission shop or do it yourself, change the gears to match the rear. see this website for example of gears available. http://www.exoticmuscle.com/webpage....EL=DRIVETRAIN. You could also get an electronic box to change the ratio for the speedo as well. Hope this helps, chris :flag
