I was on the quad when I bought it, but I only rode it once that was five years or so ago. My bro-in-law said it ran very well with them. I heard of booring them and was going that route but was able to score some V2's for cheap so I used them instead. He had the stock carb on there and that crappy DG exhaust it was jetted at 330main and when i opulled the plug it looked ok to me. So they must flow better than stock. Let me know-bob