[olddog]

Grubby

I have a TKO-600 with the .64 5th. I have 26.3 OD tires. I have everything mapped out in a spread sheet. So all I had to do is change the rear ratio, to see what you will have. If your tire diameter is different, the speeds will change by the ratio of OD change.

3rd gear 3000 rpm = 55 mph
4th gear 2340 rpm = 55 mph
4th gear 2975 rpm = 70 mph
5th gear 1500 rpm = 55 mph
5th gear 1900 rpm = 70 mph

With a .82 5th gear
5th gear 1920 rpm = 55 mph
5th gear 2425 rpm = 70 mph

I don't like the .64 5th gear, as I feel the step down is too big. It you shift at 3000 rpm the engine speed in the next gear is listed below.

-------shift RPM - RPM after shift
1st ----- 3000
2nd ---- 3000 --- 1976
3rd ---- 3000 --- 2031
4th ---- 3000 --- 2344
5th -------------- 1920
The .82 the would give.
5th ------------- 2460