For the first gen Vibes and Matrixes, the manual transmission gear ratios are :
5 speed
1st : 3.17
2nd : 1.90
3rd : 1.31
4th : 0.89 (overdrive)
5th : 0.73 (overdrive)
Reverse : 3.25
Final Drive Ratio: 3.94
6 speed
1st : 3.17
2nd : 2.05
3rd : 1.48
4th : 1.17
5th : 0.92 (overdrive)
6th : 0.73 (overdrive)
Reverse : 3.25
Final Drive Ratio: 4.53
To map RPM to MPH:
(Engine Revolutions per minute * 1/gear ratio * 1/final drive ratio) *
tire circumference (in inches) * 1 foot/12 inches * 1 mile/5280 feet * 60 minutes/hour = vehicle speed in MPH
The stock tire on a 5 speed are 78.2 inch circumference
Since the top gear ratio of both trannies is 0.73, and assuming the same size tires, the 6 speed will run slower at the same rpm than the 5 speed due to the difference in the final drive ratio.
at 75 MPH, the engine should be at about 3350 rpm in a six speed, compared to about 2920 rpm for 5 speed, not including variations in tire size/inflation, speedometer accuracy, etc
Trix04 wrote: ↑Mon Mar 30, 2026 3:53 pm
Btw, the others who have done it, I have a question. Did y’all get the 6th speed (actual 6th gear), because I only have 5 spd like the original. I run 75mph@ around 3200 rpm. Is it sound right ?
3200 rpm @75 mph is a closer match to the 6 speed, but I don't understand you only having 5 speeds
When you walk through the gears (say with engine off) which shift pattern matches your car? (ignore the diagram on the shift lever if you still have the one for the 5 speed)

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