Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

slinger - You won't be able to find a single dual belt pulley that will work.
You have to use to separate pulley's.
I put a 3.25" on my Ariens 1132 (soon to be 1332)
Here is a link where you can get the pulley's your looking for and will need
Pulleys
Actually It's 3.45" but that's close enough.
You can search by shaft size to find the other pulley you'll need to drive the tractor.
Stock on most Ariens I believe is 2.50"
When using two separate pulleys instead of the dual pulley.
You have to play around with how to put them on the shaft.
Collar forward, collar backwards.  Or you may even have to grind off
some of the collar on one or both to make it shorter to get the alignment right with the lower pulley.
But it's very do-able.
I actually cut a steel dual belt pulley in half to use the 3.25" side.
Then drilled and tapped the collar above the key way slot for a set screw.

Sorry about that, forget about what I said in my last post.  I didn't realize that your blower has a three belt system. That pulley from Grainger may work.  But your going to have to make sure
that the spacing between the two grooves is the same as your stock pulley. If the belts aren't spaced exactly the same they will never stay on the impeller shaft pulley. You'll also have to make
sure that you will be able to get the new pulley positioned on the crankshaft so that you have good vertical alignment of the belts between the drive pulley and the impeller pulley.

The problem you may run into with this. Is that the Grainger pulley has the collar with the set screws to hold it on the crank.  You may have to slid it on the crank with the collar forward. And then find out
that when you get the belts aligned vertically that the collar with the set screws is to far off the end of the crank for the set screws to do any good.  Or if you put the pulley on with the collar in the
back it may hit the other pulley before you can slid it on far enough to get good vertical alignment. There really isn't any way to know if the Grainger pulley will work without buying and trying it out.

Your RPMs calculations sound about right.  And I would agree that a 3.95" would be to large. The increase in impeller RPM will make some difference. In that you will be able to process more snow
 through the blower at any given forward speed than you could before.  Decreasing the space between the impeller blade tips and the housing will also make the most noticeable difference in the blowers ability to really throw wet and slushy snow without clogging the chute. Just a heads up, you may have to modify the belt cover with the larger diameter pulley's.