The '06 is claimed to have about 5 more HP in the midrange, with peak HP nearly the same as '05.
When you ride and '03 and an '04, the '04 seems a touch faster. With nice clutching and gearing and suspension set-up an '03 can be made to run right with or a little ahead of the '04.
The '05 and '06 will feel noticeably faster than either and '04 or '05. Partly because the rear skid transfers power better and partly because the motors are stronger. Higher compression heads and better timing curves are the biggest contributors.
A forum community dedicated to Ski-doo snowmobile owners and enthusiasts. Come join the discussion about trails, racing, performance, modifications, classifieds, troubleshooting, maintenance, and more!