I just bought a used HMF for a grizzly. I got alot more bottom and mid range power out of the grizzly. Now i can pull the front end off better and when i pull out on the road if i hammer on it i can let black marks on the road. I am please with it i also got a ngk plug that burns hotter. I didn't have to re jet because grizzlys run rich. Also all you people say HMF's are relly loud they aren't that loud mine is just right for me. It might just be alittle bit louder than my e series on my z or the same. Only trouble i had is my srews on the end cap fall out and the bolt that mounts the pipe came alittle lose. I am going to get some lock tight tomarrow to fix those problems. Also i didn't lose no top end i can still hit 61mph. I can't wait till i get my clutch kit in it shoudl have a crap load of power then!

 

Thats good to know about the pipe. I'm looking to get the complete system for my 04 grizz and was trying to find someone who has run one. The clutch kit will help out greatly. I put one in after the larger tires were installed and it worked great. The low end was restored and in the mud and deep snow it really works awesome.

 

Yeah i was thinkin about putting an HMF system on my Raptor and you just told me what i wanted to know.