When running on a dyno with manual transmission how many gears do you run through for HP/Torque readings? I'm thinking 2nd or 3rd gear might provide all the info needed but then I've never been on or near a dyno. Thanks.
Typically, you will only care about the dyno pull in whatever gear gives you a 1:1 ratio, so 4th in a 4 speed manual, 3rd in an TH350/400, or 4th in a typical 5 speed manual application. The person running it on the dyno will accelerate through the lower gears until 4th (in a 4 speed) and then punch it to your desired RPM limit. Using a lower gear may throw off the calibration of the dyno, and give you a false reading.