Do you truck guys dyno in 2nd or 3rd?
#21
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No you've got yourself backwards there. The drive shaft speed is directly proportional to the wheel speed as the ratio is fixed (3.42 or what every yours is). The only ratio that changes is in your transmission. Therefore, both your wheel speed and drive shaft speed will be faster in 3rd than in 2nd at a given RPM. Your drive shaft speed will be the exact same in 3rd gear no matter what gear ratio or tire size you have.
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No you've got yourself backwards there. The drive shaft speed is directly proportional to the wheel speed as the ratio is fixed (3.42 or what every yours is). The only ratio that changes is in your transmission. Therefore, both your wheel speed and drive shaft speed will be faster in 3rd than in 2nd at a given RPM. Your drive shaft speed will be the exact same in 3rd gear no matter what gear ratio or tire size you have.
#26
i dyno'd mine in 2nd, 3.42 gears with 32" tire 4x4 i was like 111mph at the top of 2nd lol
You always should try to dyno in 3rd or 1.00:1 ratio because not only is 2nd aprox 5% lower numbers but your tune will be off a little because 3rd gear will apply more load on the engine than 2nd
If you have a big one piece aluminum shaft do not try it lol!
You always should try to dyno in 3rd or 1.00:1 ratio because not only is 2nd aprox 5% lower numbers but your tune will be off a little because 3rd gear will apply more load on the engine than 2nd
If you have a big one piece aluminum shaft do not try it lol!
#27
I dyno'ed mine in 3rd with 20in wheels an stock 275/55/20 tires which is close to a 31 an went 150+ at 6200 an pulled fine but I was steadily walking away just in case lol.. but I do have a steel shaft from factory
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