I rode my 421 cub with just cleanup porting on 35 PWK's on gas with a +6. 10 paddle haulers and marvin shaws all around and it was fine.
If you decide to go with a +6 let me know i have mine forsale now that i am getting the motor drag ported and going to alky. There is a link in the forsale section for it.
http://forums.atvdragracers.com/index.php?showtopic=480
If you decide to go with a +6 let me know i have mine forsale now that i am getting the motor drag ported and going to alky. There is a link in the forsale section for it.
http://forums.atvdragracers.com/index.php?showtopic=480