Piston help?

[TRX450R014]

I was wondering if anyone could tell me
how much hp/tq would I gain if I put a 13.1 piston in ny 450r?I have the hrc kit,
HMF BB pipe(head pipe on the way),k/n
filter.Also should I get a wiseco,je,ross?
I do mostly trail riding and drag racing.

Thanks in advance.

[benwa450r]

I'm not sure about the numbers.... but it will help the low-end and midrange alot. You will feel a noticeable difference.

[jeepnrocks]

same here, i dont know about the numbers but i found the difference to be large. i went with a je