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3657 Views 9 Replies 7 Participants Last post by  jpierce238
Does anyone know the horsepower of the 660?
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??? I would like to ???
Seems to me I read on another forum where the grizzly was rated at 28 hp. Please don't quote me on this and I have been searching for the thread but still haven't found it yet. I will keep looking.....
I'm thinking 30-35 stock... if you put in a K&N filter, a good pipe and properly jet it, you can expect an 8-10 hp increase. This is based on what I've heard from Raptor owners, too.

according to this formula the grizzly's HP should be 38.6

HP= RPM*Torque
I went through this a little while back. According to the shipping papers that come with the 660 at the dealership. The 660 CC Grizzly has 42 HP. I do not think this is the same for the 660 Raptor, and I am not sure if this HP is rated at the engine or at the rear wheels. I suspect engine, as I have seen DYNO reports that show lower numbers. Hope this helps.
Thanks guys,

Man, a grizz has more horses than most small tractors, even some bigger ones only have 30 to 40 hp. no wonder the thing is a rocket on four wheels. and another thing, I pulled a stump out of the ground about 2 feet in diameter with no problem.
I have a stock 2003 Grizzly and would like to gain some additional horse power. Does anyone have any ideas for someone with limited mechanical abilities? Some things I have hear are: dial a jet; new pipe, billet exhaust tip, pro flow kit, k+n filter, TPI valves. Any help would be appreciated.
Went to my dealership too, and they said 42 horses.
guess you were right gumbo.
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