They are 2.86.....I am doing the same thing. If it is the powdermax it is the same track as on the 07' Addrenaline (2.25" challenger). If it is the challenger LITE, they are the trenchers because the paddles are a bit stiff.
You need to buy some aftermarket's for about $90 each or get drivers off an 06 or 07 440 Race chassis. They are 8 tooth 2.86 and are almost the same overall size as your 9 tooth 2.52. BRP...in their infinite wisdom, only sells the drivers now ON the driveshaft for $360!!! However, I found a dealer in WI that has them in stock for $53 each so I have 2 on the way.
I plan on gearing down to 20/47 (currently 20/45) so I can take some of the slack out of the chain.
Now I just need to figure out how to extend the skid to work. SLP only makes a 4", 5", or 7.5" extension so if you go with the 5" you will still need to move your skid back 1" or go with bigger wheels.
Good luck.
Rt