My rear end was changed from the stk 3.08 to a Richmond 3.55 at some point by some prior owner. I don't know who & I don't know when. I think they should have made an adjustment at that time to the speedometer cable. I've always suspected that my needle seems to jump up to 60 a bit quicker than I can really claim credit for but I now have proof. Following next to my wife while on walkie talkies, I've discovered that 60 mph on her new car, was about 71 mph on mine. The difference seems to grow as the needle pushes to the right. Has anyone ever had to fix this? It's not the biggest of deals as is -- it lets me think I'm going really fast without the worry and will probably save me a ticket or two in the long run!
~ Joe

I believe you can go to a Chevy dealer and get a different gear for the end of your speedo cable that goes into the trans. They are different colors or have some type of color code on them ( or so I have been told ).
Hopefully someone else with either back me up on this fix or post a correct one if I am wrong.

|QUOTE|glenns said: I believe you can go to a Chevy dealer and get a different gear for the end of your speedo cable that goes into the trans. They are different colors or have some type of color code on them ( or so I have been told ).
Hopefully someone else with either back me up on this fix or post a correct one if I am wrong.|/QUOTE|

Glenn,
You are right as can be. His gas mileage is a lot better now, than it will be when he changes the gear, too. His miles won't rack up as much with the right gear on it.

Yikes! Kind of horrified to think what the MPG will net out to when the speedometer is geared correctly. Romping on it now gets me only 8. Average is about 12. ~ Joe

|QUOTE|fun71 said: Yikes! Kind of horrified to think what the MPG will net out to when the speedometer is geared correctly. Romping on it now gets me only 8. Average is about 12. ~ Joe |/QUOTE|

Joe,

It probably won't get much worse. It can only get so bad. You might not even notice the difference.
I wish I had the engine that you have. Sure would be fun!!! My ol 195 HP ain't too much of a hot rod.....

The big blocks are a LOT of fun but you do pay the price in gas mileage.

|QUOTE|glenns said: The big blocks are a LOT of fun but you do pay the price in gas mileage. |/QUOTE|

While you are having that fun, does "Smokey" ever stop you to interview you for a job? . It would be awful tempting to let it all hang out....

Only met Smokey once or twice and none of those times in the Vette.

Thankfully -- no visits from Smokey or his brother Johnny!
~ Joe

there is a web site called smokemup.com that you can go to that gives you a formula to figure out what driven gear you need if you have the gear ratio of the rear end and the number of teeth on the drive gear.After I converted to a 700R4 transmission I had that problem and the local chevy dealer said I needed to get my speedometer calibrated.Of coarse I looked for a different solution that was cheeper.The smokemup site gives you the rpm you should be turning at a certain speed.The gears are not expensive(about $5)I had to order the ones I needed.Outcome was good at 70mph I turn about 2250 rpms which is what it is suppose to.