I had a bad day when I said 550-560 RWHP with the addition of a CAI and a cam. Upper 400s with a goal of 500 at the wheels would make my day. I MAY wait and save the cam money and put it toward a huffer. Drivability would be better...and so would my mileage. The exhaust is already giving me more MPG.
I got my exhaust and tune at LGM. Headers a lre long tube 17/8" and a full 3" hi flow cat-back to GHL mufflers. With the STOCK air box, Anthony tuned a couple of tenths under 40 RWHP. With a good CAI and whatever LGM recommends on the cam install (in the fall) I SHOULD be at 550-560 RWHP...and maybe more.