We all know the more air you can feed your motor-mixed with the right amount of fuel-the more power you can find from that motor. So if you were told that something as simple as an air filter could give you more horsepower, would you try it? Well, we tried it for you.
The Scramjet air cleaner from TP Engineering features a machined billet-aluminum backing plate with an integral velocity stack and chromed die-cast cover with a unique air scoop that aids breathing for added performance. Each kit includes a washable air filter, backing plate, mounting hardware, and breather kit. The kits are available for all top-breather Evo and Twin Cam engines with CV, S&S;, Mikuni carburetors, and Delphi fuel injection; other kits are available for 45mm Mikuni carburetors as well. TP claims that this air cleaner kit-a simple bolt-on part to your carb-can gain up to 5 hp, and on an EFI unit, the same if not a bit better. We have a few bikes at our disposal for testing, so we headed over to our go-to shop Horn Cycle Works in Pomona, CA, to install the Scramjet air cleaner kit on a stock '06 Heritage Softail with fishtail pipes and ran a few passes on the dyno.
TP Performance **
Horn Cycle Works