Rear end gearing calculator
 

A few years back someone posted a link to a rear end gear calculator web site. You would select your motor, transmission, and gears. And then you could put in a MPH and it would tell you the RPM or vice versa.
I my speedo seems way off and I want to confirm. It would be nice to know if im going to get a speeding ticket or not.

I've used his one before:

ULTIMATE PONTIAC GTO PICTURE SITE Text Topics article #29

If you have a smart phone, download a speedometer app. GPS is accurate enough at constant speed.

i like this calculator: Gear Ratio Speed Calculator

I whipped this up for ya... Assuming you have a T56.

The Flyin Miata website that has one that works for factory Miata rear ends and also has choices for V8 swap specifics.

In my area, there are numerous speed limit signs with a radar display below the sign showing your speed. San Antonio must be more relaxed. :-)

It's in Texas.:drama: