Where can I find a cheap aftermarket speedo?

[sixpack_sid]

I just finished my 68 Charger. I took it out for a spin to test drive it and the speedo doesn't work! It was showing 60mph when I was doing about 25! I put a new cable in it when I restored it. I would like to put in an aftermarket gps or something that I can hook into a power outlet plug. I  don't know if a GPS would show the speed if I don't have a route planned so anyone have any suggestions on what I can get? I don't want to rip the dash apart to fix it. I'd rather just hook up something aftermarket. I don't want to spend a lot on it.
Thanks,
Sid

[440]

Personally I would get the gauge rebuilt and calibrated. Shouldn't be too expensive either.

[DC_1]

I just finished my 68 Charger. I took it out for a spin to test drive it and the speedo doesn't work! It was showing 60mph when I was doing about 25! I put a new cable in it when I restored it. I would like to put in an aftermarket gps or something that I can hook into a power outlet plug. I  don't know if a GPS would show the speed if I don't have a route planned so anyone have any suggestions on what I can get? I don't want to rip the dash apart to fix it. I'd rather just hook up something aftermarket. I don't want to spend a lot on it.
Thanks,
Sid

GPS will show speed even if you don't have a route planned. I would just use that and leave the original speedo in the dash. It will look better than hacking in an aftermarket in the dash somewhere..

I agree with the other post, save a few bucks and get your original repaired or find a working used one one eBay

[Troy]

It's probably the gear in the transmission. They are interchangeable and should be based on your rear gear and tire size.

Troy

[John_Kunkel]

If the speedo drive pinion in the transmission is the wrong one the odometer will also read high. Find a place with a known distance and compare it to the odometer reading, if the odometer reads high you just need to find the correct pinion and the speedo will likely be closer to correct too.

[bull]

You can also ask a cop if he'll check it with his radar. Or get a couple of walkie-talkies (or cell phones if that's still legal in your area) and find a buddy to pace you on the road and compare speeds. Based on that info they should be able to tell you which gear you need.

[sixpack_sid]

  I put an engine & trans in from a 77 New Yorker. I also have big tires on the back. Maybe the gear is the wrong one then. I'll try the odometer test this weekend and see if that runs high also. If it is the gear, how do I figure out which one I need? And where can I find one?
Thanks!
Sid

[440]

http://www.dodgecharger.com/forum/index.php/topic,91501.msg1037984.html#msg1037984

[sixpack_sid]

I jacked up the rear tires today and spun them to get the gear ratio-The drive shaft turned 3 & 1/4 times with one tire rotation. My tire size is 275x60x15. So I figured it's 3.23. From this website http://www.mymopar.com/speedometer.htm
I figure that I need a 31 teeth speedo gear. But I can't find that size on Summit. They have a 30 tooth speedo gear or the next size is 34. Which should I get?

[c00nhunterjoe]

Where did you find them on summit? All I could find was ford and gm gears. I would get the 30 in your case if you can't get a 31

[Troy]

You can still get most of them from the dealer. However, as usual, the most desirable ones have had the price jacked up to about $90. I have had good luck finding them on eBay. It's not like they go bad (usually).

Troy

[sixpack_sid]

Where did you find them on summit? All I could find was ford and gm gears. I would get the 30 in your case if you can't get a 31

You're right-they are GM & Ford. I was too busy looking at the teeth, I didn't see the make. I have the Charger in my saved vehicles and thought I was in that window, but I guess I wasn't. I found some on eBay. I'll check it out this weekend.
Thanks!

[440]

Did you count the teeth on the gear you currently have ?

[sixpack_sid]

No I didn't pull it out yet. I looked on a spare tranny and that one had 26 teeth.