Sorry, I think they are getting CAIs, I just typed lid. The +38HP was the biggest claimed increase, but there is a dyno posted for a 30HP gain with CAI + tune.

 

A lot of the restriction of stock airboxes is baffling to reduce noice to meet standards. Changing the lid on my T/A and loosing all that stock box crap made a very noticable difference from the Butt Dyno. Plus the sound was MUCH better. Same for the CAI on my 06 Charger Daytona. Noticable power, especially in the higher rpms, and sounds down right mean. Plus I just feel better knowing that my engines are getting more fresh, colder air regardless of what the actual RWHP gain may be. I know I will get the first K&N CAI I can for my new Camaro.