what size rear tire are u running? This will help you decide the best gear ratio. What size slick are you useing? The taller the tire, the lower the final drive ratio will be. What rpm will u go through the traps at? What RPM does your motor make the most power?
A combination of desired RPM and tire size will determine the best ratio for your combination.
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1993 GT/AOD
'93 Mustang GT