bseif1122

I have a 1990 ZR1 vette with a ZF 6 speed manual tranny. rear differential gears have been changed to 4.10 ratio (estimated- did not count teeth but measured propshaft rotations compared to wheel rotation). the speedometer is off and cannot be corrected by using OEM speedo gears. it has electronic speedometer with the sensor that is installed into extension housing. the sensor is driven with gears just like a cable style. is there a electronic "cheater" module available that I could install that will adjust speedo to correct speed. or does anyone know of any places to get drive and driven speedo sensor gears to correct the speedometer.

ccmano

darklordftt

I used this as well
http://www.atrol.com/era.htm

you just divide your old gear radio by your new radio (or vice versa, I don't remember) and that is the input for the device. My 89 went from 2.57 to 3.73 and the Speedo is dead on.

WVZR-1

I have used Abbott in the past (several years ago likely 15 +) for vehicles that there weren't mechanical corrections possible. This OP posted in multiple C4 'sub-forums' at the same time (as many do) so I expect if he was serious about correction he's accomplished it. Abbott at the time was substantially more expensive but at the time the device used by SLP was having issues and others used by the FOMOCO folks were also having issues. When those were removed and replaced with Abbott I don't believe anyone mentioned issues. Abbott does many product that are used in commercial fleets and I was familiar with most of their product. Many don't want to spend the $$$$ - I don't know how expensive now but back then it was substantially more than the DD BUT IT WORKED!!

darklordftt

I do remember it being more expensive than the other option(s) as well, but everyone on here gave it good reviews. I think I spent $180 total on it last year.