Anybody know if the 500HO cam will fit the 425 head and if a 38mm carb will work? Looking at the Polaris manual, it looks like it will work. Am I missing something that may keep it from working?

 

Cam wont work. Different carb configurations are alway available from someone. I havent had too much to do with 425 performance enhancements, maybe someone else has.

 

I don't mess with 425's much either . I do know the cam profiles on a 325 and a standard 500 cam are identical (not the HO cam , it has more duration ) . The physical attributes of the cams make them unable to swap , but the valves open and close identically . I ASSUME the 425 lobes do the same . (please don't skin me if I am wrong ) I would suspect a cam with an increased duration could be custom made for you for around $150.00 .

So , I guess the answer is no , the 500 HO cam won't fit , but , your stock cam could be made to do the same thing as a cam from an HO for about the same amount of money .

 

Or even better than the HO cam!

 

That is correct DieselPro . You could probably squeeze more duration out of the cam , but the lift in stock form is limited by seal to keeper clearance . Polaris's run minumum clearances frequently in there valve trains . The 425 is probably the same way . Shortened valve guides could be done , but the costs rise .

 

ChopperBill,
I would have to say that you are wrong in thinking that the cam will not fit. The heads have identical part numbers (425, 500 and Scrambler). The cam that is in the 425 has the same part number as the cam in the 500. Since these two critical pieces have the same part number I would think that the cam out of an HO would fit. I got the info right out of the parts manuals on Polaris's web site.

 

Oops! Found a parts fiche error. While checking parts numbers putor had a glich and went to the parts fiche. Number for the cam in the 425 fiche I looked at was the same as a 335. This isn't the first time this has happened. Kept getting 335 stators for 500's. Thanks for catching that error. I should have double checked my info before announcing on the forum. Still can't tell you what would happen with this conversion due to lack of experence.