Ok i was thinking about putting a 385 bore into my 300ex. I wanted to know if anyone has is because i want to know if it makes a world of differencer or just a lil. Thanks. Ryan

 

If no having reverse isn't a big issue for you, go with a 350X engine conversion. These engines have far more potential than the 300EX engine. Check out Powroll.com for info.

I have a 350X engine in the classified section here for sale. It's never been ran. I put one of these into a 250X a couple of years ago and it had no problem staying with a 400EX anywhere.
[When you could keep the front end down.]

 

Anything over a 330 big bore kit for a 300EX is a bad idea. The trannys are a weak link and you'll be going through them right and left. Do what knowsalot said and go with the 350X engine.

 

ya but where do I get a 350X motor?

 

Anything above the 352cc kit is a handgrenade, trust me. I have the 410cc kit and am going to a 350x based engine this winter. More power and durability.

 

Will a 350X beat a 385 kit? And where do I get a 350X motor?