Just built a 501 and bought a fcr carb to be bored for it. My first question is what intake is a good combo to run with the fcr carb? I was going to purchase a esr intake but I thought I would ask around first and see what other guys are running. My next question is I bought a fcr carb off of a 2007 trx 450er how big can I bored the carb before it gets real expensive? I read that some carbs can go to 42.5 but after that the price doubles.