big bore for 300 ex

[chad400]

what size kits do they sell and where can i get one from???friend wants to do his motor

[m250r]

330 and 350 are the common bore kits

Try: Powroll, GT Thunder, TC - They are the top three probably

[bradley300]

you'll have to call gthunder about the 350 kit, but there phone number is on the site www.gthunder.com