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Did you add in the secondary reduction when you did the math?? Its 2.352. (The reduction from the crank to the clutch basket). I could not find the same site that I googled at first, but this site agreed on the ratio's: http://www.dixonarchive.com/hayabusa/performance1.htm Many of the sites I checked did not include the secondary reduction, but showed the same tranny gear ratios. They are theoretically correct if all you cared about was the tranny. If you didn't use the secondary reduction your numbers would be less than half. Remember this shit can't be wrong because I found it on the internet. I also gestimated on the torque figure.... Dunno what a turbo does to it but all the horsepower numbers were at around 10K-RPM so torque would be around half of horsepower. (torque = (horsepower x 5252)/engine speed) Ok, so the stock 2008 has 178 HP at 9800 Rpm, gives us 95ft/lbs. (Peak torque was actuall at 10,200 but I am to lazy to convert it from metric) So with our reduction (2.352 X 2.615 = 6.15) (6.15 x 95 ft/lbs = 584.25 ft/lbs) And if I understand correctly you plan on running a turbo so it will be worse. Surely 600 Ft/lbs wouldn't hurt a box designed for 40 hp? I know you don't need a math lesson Fabr. I just wanted to show everyone how I came up with the numbers. I even used a calculator so it must be right.
Well, 600ft /lbs at 350 rpm is only 40 hp... Just kiddin ya. I've been preaching this for a while over at mbn and no one but fabber has believed me. If you kept the bike in 6th but shifted the car trans then that would be better.
If the torque values were based exactly what the wheel input into the dyno, then a different wheel size or different gearing would yield different torque numbers.
I don't have any techy print on hand. A ft/lb is 1 pound acting on a lever that is 1 foot long. Is the radius of the tire is 12 inches, that is one foot, and that would be 105 lbs acting on the outside of the tire. A dyno measures everything in hp, then converts back to ft/lbs. This is how I understand anyways. HP is basically just a power figure like watts. 746 watts is one hp. Once they have the hp numbers, it doesn't matter where you take hp from, you will just have some loss the further down the line it is. To find the torque, they basically take the hp number at a particular rpm, multiply by 5252, then divide by the engine's rpm to get torque at the engine. To find the engine rpm, if it's not hooked to a tach, they use gear ratios and the speed of the dyno to calculate backwards.