In order to show 8 - 15 Hp gain with an air cleaner and tubing, you would need the most restrictive filter (stock that is ) imaginable. Most of the companies showing those gains do flash runs on a crank dyno. In other words, they blip the throttle and take flash readings on the results. Those gains aren't sustainable. I've been doing this a long time and my original comments stand. Saskins as usual everything you said is wrong. If your engine is detonating its ready to blow up. Thats because your timing is too far advanced or your fuel has to little octane or several other things ( none of them having to do with air filters). Adding cooler air isn't going to help. You really should learn a little before you open your mouth and swallow your foot. Your posts are actually becoming fairly amusing. I imagine that when you go out to the race track, the real racers just smile at each other and change the subject when you start talking.