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GRADYS Performance · 08-24-2016, 01:30 PM

Go to TCIAUTO.COM they have a calculator in the technical resource section that will tell you exactly what gears you need. 3 of the following 4 are needed to figure out the fourth.

Tire size or Diameter

rear end gear ratio

drive gear tooth count

driven gear tooth count.

Drive gear is on the output shaft of the transmission. Count teeth thru speedo housing hole or take off tail housing to count.

08-24-2016, 01:30 PM	#2
GRADYS Performance Registered User Join Date: Dec 2013 Location: Columbus, Oh Posts: 367	Re: A little speedo gear help needed please. Go to TCIAUTO.COM they have a calculator in the technical resource section that will tell you exactly what gears you need. 3 of the following 4 are needed to figure out the fourth. Tire size or Diameter rear end gear ratio drive gear tooth count driven gear tooth count. Drive gear is on the output shaft of the transmission. Count teeth thru speedo housing hole or take off tail housing to count.