Big Valves in a 300ex?

[chapmanmd]

PLEASE dont tell me to search, cuz I already have...

I have a FST 330 kit, 11.5:1 piston, TC National Cam, Full Yoshi exhaust, WELL jetted carb, FST ported, etc.

What I am wondering is whether bigger intake or exhaust valves are going to help me get more power, and at what cost? I dont mean dollars, Im referring to seats being lapped and having valves sucked up into the head.

Any suggestions other than continue searching?

Thanks.

[dork]

my buddy has oversized intakes in his 300ex with a 380 kit. i'm not sure on the price, he had the head ported and valves put in all at once. FST did it. from what i can tell it looks like the stock seats were used, just opened up for the bigger valve. the seats are ground out past the stock angles, and then recut with 3 angles. if done right, the valves won't be sunk into the head anymore than stock.

i can't say how it would run with stock valves, because everything was done at once. but his revs very quick and pulls long on the top with good over rev. i would say its worth it, especially with the 300's since they have small valves. on a head like that, bigger valves will benefit across the rpms, not just at top. you don't need to run tons of lift to get the same flow.

[Cody_300ex]

Didnt search hard enough, http://www.exriders.com/vbb/showthread.php?s=&threadid=193912