I have added a Diamond G snorkel, a twin air filter, a Nyroc exhaust with six 3/8" holes with no spark arrester, and 145/142 jetting with stock needles shimmed with two #4 brass washers per needle at an altitude of 0-1000 feet for a 2003 650. The book says 42 hp stock, but as a guesstimate, about how much horsepower do you suppose I know have with those mods? Thanks for any guesses.

 

If you want to know exactley, if you ever come to the Hatfield McCoy trail system in West Virginia you can contact M&J Sales in Chapmanville at 304-855-3122 as they have a Dyno just for Quads, Bikes and Carts. It is a Dynojet system and that thing is awesome..

 

I'm only 70 miles from the Gulf of Mexico. That's just a little too far for me to make. I was hoping someone might have a guess.

 

My guess ...... about 45 or 46 now

 

do a forum search, I read a post a while back where someone did a dyno test it seems like they said the Nyroc exhaust mod with jetting can add about 3 or 4 hp and a snorkle/filter/airbox lid holes set up can add up to about about 1 hp. I also would guess you have about 45-46.

 

The muffler mod if you stayed stock jets without the intake you will come out with a %9.35 gain. Since you are realatively low altitude you should be somewhat higher say %9.75 gain. With the air box and intake modds you should have another %2 - 3 higher index.

For example going with muffler modd, intake, ported polished heads, bored ported polished carbs, 150 - 155 jets I am only %15 increase in power. A 10 percent gain is substantial on a 42 horse power engine an extra 4-5 horse is very noticeable. Hope this helps.

 

4-5 hp is noticeable, says the man with a supercharger!