Thank you Todd, for your time and effort doing the build, testing and posting.
To compair chassis dyno results. all you can look at is the percentage of gain, and even then has to be taken with a gran of salt.
Hunter works, with a bolt together std bore and all stk intake other then a couple TPI valves went from 27RWHP to 52RWHP or a 93% gain.
At the engine, the stk Teryx makes 45HP and with that kit setup the way they are makes 90-93HP which is a 100-106% gain. If they had clutched it for the dyno, they probably would have seen the 100-106% gain but then they would have to reclutch for the field to get the best performance in the rear world.
Now I'm going to use some of Dasa's numbers, because they have so much time in testing 840's. (hope you don't mind Dasa)
Thier dyno shows 36RWHP on a stock Teryx. They went from 36RWHP to 67.5RWHP with a bolt together 840 or an 87% gain.
As above with porting 36-70.6RWHP or a 95% gain
As above but with big valves, porting and big throttle bodies 36-76RWHP or a 112% gain. I'm not sure which of those were with Dasa's exhaust which they said makes 6-7RWHP over the Muzzy that Todd dynoed with.
Now back to std bore, same kit as Todd did, just bolted together but with 39FCR's dynoed on Pro Shop dyno (Dynojet same as Hunterworks)
Went from 27RWHP stk to 71.6RWHP or a 165% gain. Now that sounds like a huge gain right, should be around 95.4RWHP on Dasa's dyno right, 36 =165%=95.4?
Wrong, That kit with 39fcr's and stk heads makes 108-110HP from 45 stk or a 140% increase. Why did it show 165% increase at the RW's? The FCRS give increadable throttle response and spike the HP, same as bigger displacement does or higher compression.
They also tuned the clutching a bit for the Dyno, so that and the FCR bottom end hit shows an extra 25% RWHP that isn't really there.
So again, with CVT's, chassis dynos are great for jetting, but as I and everyone else that understands CVT's have said for years, you can't really judge performance based on RWHP with a CVT.