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the busa specs calls for 187 hp and 99 foot pounds of torque at the crank.I have a dyno chart here with actual rear wheel numbers, 151.17 max hp and 86.14 max torque..the red is the stock numbers, the blue was the initial pull on a motor I had built that ended up putting 220hp to the wheel, but I can't seem to find that sheet, although I have a sheet showing 212 and 105.96 foot pounds of torque, he had problems getting traction in 5th. gear over 3/4 throttle...
that dyno chart is measured at the wheel, the crank numbers are higher...
Your gonna have a lot higher torque number in the lower gears because the ratio is lower, but that ratio basically stops at the final drive, or actually the center of the wheel, you loose torque as you go farther out on the wheel. You would have a lot higher torque number if the drive train was hooked directly to the dyno, the 24" tall wheel eats up a big chunk of that torque.Think of a wrench, you can put hundreds of pounds of torque on a 3/8 bolt by hand and spin it easily, even stripping the threads if you wanted, but if you had an adapter to attach to a 2 foot in diameter bolt head, and you still had the same torque wrench, which was a smaller than the wheel, you couldn't apply much torque at all and wouldn't get the bolt snugged very tight. That why you always strip smaller bolts a lot sooner than a bigger bolt. The high torque numbers are seen by the chain and gearbox which is why they always break, not the outside of wheel, ut given enough power and traction, you could break the studs attaching the wheel to the drive train because the closer you go to the center of that tire, the more torque you will see..
Yoshi your understanding is mostly correct but in red is not.Any torque multiplication stops at the rear wheel axle but with a 24" tire you only lose 1/2 of the actual FT lbs of torque at the rear axle...24" /12" =2:1. That is a lot but a lot to the extent that I felt the rest of the reply would indicate.Say the ACTUAL measured tq at the rear wheel was 400#' the tq at the rear axle would be 800#'.