Does anyone know the approximate bhp gains of the K&N Typhoon and Racing Beat REVi (with and without the Ram Air Intake Duct) intake kits with a stock 6 spd setup? Also, what are some other good systems for less than $600?

If you look you can find the answers. It will be around 3 hp.

No intake gives you particularly big gains. The ram air duct is beneficial at higher speeds and can't be measured on a dyno. Dyno's can't account for airspeed. Many people have reported mileage gains with the REVi and ram air duct installed. On the first Typhoon systems, many reported a loss. Not sure about the current one though. I'm not going to find out.

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