ThunderPaw
Husqvarna
B Class
I installed the 530 kit (from Motorsportz) on my 08' 510 about 6 weeks ago while i had the engine out to replace a failing cam bearing. As a data point, the stock piston and cylinder looked GREAT, with ring gap in spec. at 10,000+ miles. The 530 kit adds very noticable power accross the RPM range and is most welcome down low. I expect fewer hot stalls in the tight stuff when i get back off road. Suprisingly, viberation is no worse and may even be a little better. I also did some mild porting to soften the casting seams and a mismatch at the intake to port seat. Very easy to do safely with the right dremel bit. Very happy with the modification: Down side... tires go to rubber dust land that much quicker!