3.73 gear recalibration

[IronMan]

I have the hook up at a local cheverolet dealership that has a rather advanced service department. They are really known for their service. The guy there told me he could recalibrate my speedo to any gear as long as it was a GM gear ratio, i.e. 3.23, 3.42, 3.73,4.10. He told me he would do it for $30.00! He would be doing it through the computer that plugs in the diagnostic port. I have 3.08s and was going to go to 3.42 because people were saying that the Jet SCU has trouble recalibrating for over two gear sizes. Well, my question is, Can this be done through my diagnostic? Can he recalibrate to a gear as low as 3.73, because the lowest gear in our cars is 3.42. I would rather have 3.73s from what I here from people on this site, but I want my speedo and shift points to be correct. Someone please help me out! thanks

[pgriffith]

I dont know for sure if it can be done. But why not have him recalibrate the speedo before the gear swap. That way if there is a problem and for some reason he cant do it. Your not stuck with messed up speedo. And if he can do it and what he says is true then you will be getting hooked up fat and you can put in your 373's. But again if it dont work you can always try the SLP speedo calibrater.

[IronMan]

Thaks for the response. What I want to know and have not found a concrete answer is how well people like the 3.73s compared to 3.42s, remember I am going from a 3.08 so both should be a big difference. btw my car is an A4 and is NOT an everyday driver, just a fun toy for the weekend (a money pit). So my questions are:
1. For those of you with 3.73s, how well do you like them?
2. If you were in my situation, would you 3.73 or 3.42?
3. Is there an abundance of wear and tear on the engine w/ 3.73s?
4. Can your speedo be recalibrated accurately w/ the slp SCU or the Jet SCU, in case my diagnostic hook up does not work? In other words for you guys w/ 3.73s, how accurate is your speedo and shift points? Which one works better?
5. How about the top end performance, such as cruisin' along @ 65 mph and punching it to 100 mph?
I would much appreciate precise answers to these questions from people who have been through this process. Thank you in advance for your replies.

P.S. I have everything else I need for the install except the gears b/c I am trying to figure out what gear to go with. Also, I have a power adder, NOS 5175, just in case that makes a difference.