Re: Workup to 900F Cam Swap

Posted by crestview750f on
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/Workup-to-900F-Cam-Swap-tp4061837p4061840.html

Tools1,
I did some reading regarding parasitic loss that could be considered corrections; my question is the factory's claim of 76 hp: at the crank or at the rear wheel?  Makes a difference since the dyno is the "rear wheel."

One correction is friction loss; depending on the engine, it could be as much as 15%.  That would render a formula of (56/0.85)-56=9.8.  Add the 9.8 to 56 and we get about 66hp; near the 76hp claim by the factory.

Here's the link to a good read .  Not wanting to add correction factors unnecessarily, and perhaps skew the data/hp results, I'll just stay with using the same dyno, same soft/hardware, and the same dyno operator.  The results will be the results; whatever hp I gain, others can determine if the swap is worth the investment and make an informed decision.

Another factor the dyno operator mentioned was "different tire, different results."  Kenda 761 factor may be worth some mental brain power.  ;)