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Old 01-19-2017, 12:13 AM   #1
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Part two is now up! Does fitting an underdrive pulley give more horsepower? We fit one then go to the rolling road to find out!

https://youtu.be/CvFdH11y4EI

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Old 01-19-2017, 06:58 AM   #2
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Part two is now up! Does fitting an underdrive pulley give more horsepower? We fit one then go to the rolling road to find out!

https://youtu.be/CvFdH11y4EI

Is this 273 wheel hp or does the dyno convert to crankshaft hp?
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Old 01-19-2017, 07:00 AM   #3
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Is this 273 wheel hp or does the dyno convert to crankshaft hp?
It is calculated, in one of the videos (maybe this one somewhere or another rolling road video, maybe the one with the 996) the dyno guy briefly changes the screen to show the actual wheel HP read by the dyno - it is a fair amount lower.
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Old 01-19-2017, 09:43 AM   #4
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Part two is now up! Does fitting an underdrive pulley give more horsepower? We fit one then go to the rolling road to find out!
So if I understand correctly, the Dyno's calculated total horsepower is still 273 after fitting the underdrive pulley. Do you have the wheel horsepower figures for before and after? Would like to see if there is a small bump in the net amount reaching the rear wheels, that is what I think the underdrive pulley gives you. (Besides saving your power steering pump at the track.)

PS, great video! If you decide to improve editing quality as discussed in the comments to the video, that would be a bonus, but they are teriffic as is!
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Old 01-19-2017, 10:31 AM   #5
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So if I understand correctly, the Dyno's calculated total horsepower is still 273 after fitting the underdrive pulley. Do you have the wheel horsepower figures for before and after? Would like to see if there is a small bump in the net amount reaching the rear wheels, that is what I think the underdrive pulley gives you. (Besides saving your power steering pump at the track.)

PS, great video! If you decide to improve editing quality as discussed in the comments to the video, that would be a bonus, but they are teriffic as is!
Yes, please post the wheel hp differences, if there are any.
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