Thought I had a Sure Grip....

[68suprB]

Thought i had a 3.23 sure grip in my '68 Super Bee (fender tag said so), after taking out the 3rd member, counting the teeth and looking at the diff I now know I have a 2.76 open diff. I'm thinking it was blown up at some point and someone put in a junkyard donor...no wonder it wouldn't spin the tires.
I bought 3.73's for it because it was a total dog on the low end (thinking I had 3.23's in it) but now I don't know what it will be revving at highway speeds with the 225/70/15 tires I have on it now, anyone have any guesses? It's a 4 speed, I've found a few speedo calculators but none seem to have the 3.73 setting on them...also what speedo gear should I be using? Its pretty far off right now.

 

[wedgie]

http://www.moparts.org/Tech/tech/pages/speedo.html

 

[1badstroker]

how tall is the tire? I'm guessing the tire is about 26" tall which would call for a 38 tooth tranny gear to get the speedo right with a 3.73 gear. If it is 27" it would take a 36 tooth gear. hope that helps?

 

[brandon64]

If you end up wanting a 3.23, I have several of them.

 

[68suprB]

According to this calculator: http://www.miata.net/garage/tirecalc.html
it says it's 27.4" tall...they have several on year one's site but i have no idea what to get...there are a few, for example, that are listed twice with different item#s... but they don't specify exactly what year they apply to
thanks