825psi so now i need a bigger cooler 99 xcsp ??

Welcome to the forum!!! I can build you a custom cooler if you like look at my site I have diy coolers or I can custom build you one if you want.

Brad

Cooler

Brad's U cooler would replace the stock coolers that you have and be probably the best option. I have a similar set up on my ProX with a 660. If you want to go less money, you may be able to add a rear cooler from an Edge chassis at the rear of the tunnel and plumb it into the hoses on your current cooler. It just revets to the bottom of the tunnel. Add scratchers and it may be enough to cool it. Next option would be to do that and add running board edge coolers from like a RMK and remove the stock XC tunnel cooler. May still be marginal becaus the RMK also has a front cross over. I ran a XCR motor in a Gen II RMK chassis and it would run hot until I added scratchers. It had all 4 stock RMK coolers. Front crossover, running board, and rear cooler.
Brad's cooler will be lighter and cool better than the stock RMK stuff.

I'm not sure you'll need more cooler. The '00 and later XCs had the same cooling system and ran 800 motors and cooled just fine. The 825 isn't significantly different than an 800 so I'm betting you'll be just fine with the stock cooling.

sled_guy