Speedometer adapter
 

I just installed a 2004r in my 65 Gto. Speedometer is way off. is reads as follows .

Speedo garmin
30 reads 25
40 32
50 38
60 46
70 55
80 61
90 70





What adapter do I need ? I think that it will have to a 90 degree for space reason. Where can I get one for the best price Thanks Bill

What tire size and rearend ratio? Have you checked what size drive and driven gears are currently in the trans?

Try this one, just need rear ratio and tyre size: http://www.montess.org/speedo_gears.html

And gears are available from here: http://www.ckperformance.com/List/20...ars-Components

Just going by this and making many assumptions.

3.42 rear axle
tire diam 26.8 inches
drive gear 13
driven gear 26

--- IF those are what you have swapping to a 10 drive gear will put you real close, just over 1% error.

Adapter for speedo
 

Called Art Carr at California Performance Transmission , He just needed what the speedo said when my garmin read 50 mph $75 Life is good Thanks for the replies . Bill