Other than just putting the new dash in... How would one go about getting the car dialed in correctly to read the right speed? I've been pondering about doing a 140mph (G92) speedo in my car for a while but never really thought about what it might take to do something like this. I'm getting a 3.42 rear end in a few weeks so I figured now would be a good time to do it since I'm gonna have to screw with the speedo anyways to get it to read right.

The speedo in the dash is a direct-swap, no special changes are needed. However, swapping the rear end will require you to change the speedo gears in the tranny to make the speedometer read correctly.

You don't have to recalibrate the needle or anything when swapping dashes? Or does the new dash come with the needle too. Hmmmm

Swap the cluster. You'll then need to replace the speedo cable driven gear in the trans tail section.

If I'm going to 3.42 gears, can I use the speedo cable gear from a G92 car? I think some of the G92 cars had like 3.45 or something like that, so it would be slightly off just a tad. Otherwise, do you know where I could get one that would work perfectly.

Are you getting the complete rear end from the donar vehicle? Is the donar complete? Is this the same donar that is also supplying the cluster? If so, you might pull the speedo cable from the transmission tail and remove the driven gear. Make note of the color of the drive gear inside the trans tail section. Hopefully, it'll be the same color as the drive gear in your transmission. That would be simple, the rear gearing, trans and speedo will be correct. If the drive gear in the transmissions differ in color, then you'll need to purchase the correct driven gear based on the color of drive gear in your transmission.

I was under the impression that you might have to change the gears when you swap the speedo (without getting the rear end). I would think that getting the gears from the rear end would do the trick unless you actually have to change it for the speedo as well.

God bless digital guages, they sure area easy to calibrate when all these changes take place!
It might be something to think about.

The rear isn't even coming from a 3rd gen. It's an LS1 10 bolt, and he's not taking the transmission apart either. So I'm only getting the complete rear end.


I'll have to figure something out.

there is also a inline reduction gear that you take the spedo speed vs. actual speed and figure out the reduction but it slip it in and your good to go

http://www.dakotadigital.com/index.c...rod/prd126.htm