definitely check all your hoses - esp the vacuum ones
also it'd help to check your spark plugs ( have you ever changed them since you've gotten the car? they were one of the few reasons why my car had only put out 202hp when cars with less mods were putting out like 257 )

-edit- another thing - check your A/F ratios, see if they're way out of line or anything ( just assuming since I didnt see anything about aftermarket a/f stuff )