WR200 pistons run in .8mm increments instead of the even numbered ones blaster's use.
Instead of 195cm³ in stock format, the properly sized WR200 piston is used to get nearly EXACTLY 200CC's (199.8 CM³ as stated) per class rules.
If you've got the money and time, and winning is paramount you'll do what's needed to squeeze those extra few cc's out of it...