Check for boost leaks, simple leak down test should work fine. Check timing of course. Run the ECU diagnostic while you are at it for peace of mind. Also, how do your plugs look? Black and wet with fuel carbon buildup, white, etc?
Also which fuel pump are you running, the stock NA pump or a TT pump. Note that the stock NA pump is rated to roughly 300hp or so. The stock TT pump is "supposed" to be able to handle 500hp+. Also, you can consider the Warlboro 255LPH as a cheaper option.