This weekend I decided to finally fix a problem I had in the Vette since I bought it 2 years ago. I found since I got a GPS that my speedometer was running about 10% fast, potentially since the tranny was replaced around 2008 with a Tremec 5 speed. They wired a Dakota Digital signal convertor under the hood to fix the speedometer signal, but didn't add any slack in the wiring so I've lived with it for the last year or so.

Found 10' of 4 strand shielded wire on EBay was just a few bucks. Yesterday I pulled the Dakota Digital box and extended the wire about 7' and it can fit through the wiper area into the passenger compartment so even the passenger can do the adjusting if desired. 15 minutes on the road today with the GPS and I was able to get it within .5-1 mph from being exactly accurate (at 60 mph per the speedometer, it shows 59-60 mph on the GPS). Unfortunately you need to be driving the car at speed to adjust the speed conversion, which meant either rent time on a dyno or extend the wires like I did and do it while actually driving. The box the converter is in was big enough that just coiling the wire up, it all fits in the box. Shouldn't be a problem since the wire is shielded and drove it today for some distance and showed pretty much right-on per the mph shown on the GPS.

Always wondered why if I set the cruise control at the posted speed, I always had almost every car on the road try and run over me. I figured out why once I got the GPS, I was doing about 54 mph when the speedometer showed 60. I was driving via the GPS all the time so I knew what speed I was actually going. Now it's doing 59-60 mph when the speedometer is showing 60 plus the odometer should now be accurate too.

Yesterday was 2 years that I bought her, today was my birthday, seemed like a good present for both of us :-)

Happy birthday, and yes, that seems like a nice present for you both.

Happy B-day glad you got that worked out........

It's little fixes like that that make driving fun again. Within a mile is more than good enough, since the Vettes used mechanical gears to determine the mph and there can always be differences/variances in tire size, etc.

Happy Birthday!

Happy Birthday and congrats on a nice little cleanup/fix!!!

You drive 60 on the freeway? Clearly not a california native!

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Around here there's a policeman or highway patrolman (or woman) every couple of miles with radar it seems. It's cheaper to stay out of trouble than get out of trouble.

I found a Dakota Digital speedo adapter in mine, when I converted the Z to automatic.

It even had a few strands of the leads connecting it P-F-T-T-T !!!!!!!!!

AND IT WASN'T EVEN NECESSARY!

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Looks like it's wired up the same as on my 5 speed

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Yup - I pulled mine, and with schematic from Dak Digital + TCI for Tranny Controller Module, got it by-passed.

Solved the problem of speedo showing 36 - 104, IN MY CARPORT (or anywhere idling)...