KX 310 Big Bore Kit?

Sep 9, 2007
Hey, I have a 2003 KX 250 and am curious about the 310cc kit Eric Gorr has. I've read a bit on it in some old posts but most of the posts were from 2001 and would like a fresh take on the topic. I do most of my riding in the woods and the KX works great but as they say "There's No Replacement For Displacement!" I do alot of my riding with my father and his KTM 525. We got the whole 2 stroke vs. 4 stroke and green vs. orange thing going on and he loves it when I can't loose a man in his mid 50's on an orange 4 stroke on the trails. Granted he's got over twice the displacement but I figure a 310 kit would even up the odds a bit. The way I have been building up the bike so far is to strengthen the low to mid power to make it more enduro friendly and get a few extra ponies in the process. The questions I have on the 310 kit are:

How much does it cost?
Do I send the whole engine or just the top end?
Porting options?

Any answers or info would be greatly helpful and appreciated. Thanks :cool:
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