My problem is -- I have a 64 Falcon Sprint (I Know it's a Brand X) with a AOD transmission, 8" rear, 3.80 ratio, and 245/60-15" tires. The speedometer drive gear in the transmission is a 8 tooth and with My setup the correct driven gear is a 23 tooth. -- I haven't been able to get a 23 tooth gear that works without being chewed up. It seems that they all enter into the drive gear at the wrong angle. The max OEM - Ford gear is a 21 tooth. -- Currently I am using a 21 tooth gear, and My speedometer is off by 10%.
