stillmatic wrote:I thought you were talking about the intake manifold. You should refer to them as cold air intake or CAI.
Anyway, keep the stock air extension and spend $10 on a maf adapter and cone air filter. That's all you need to make your car breathe better. Don't expect any horsepower gain if you have an N/A. If you're lucky, you might gain 1HP.
If you want cheap power, get an ASP underdrive pulley. They go for $99.95 at rpmoutlet.com and you'll gain more power than a intake/headers/exhaust setup. If you combine all 4, then you might have yourself a quicker car. People normally skip on the headers though, because you're better off saving your money for forced induction.
Another thing you should look into is a ground wire kit. I heard they make your car rev quicker (just like the CAI) and idle smoother.
Everything you just said is unsupported.
One of the largest gains on the N/a KA is found with an intake or a header upgrade. While peak gains may be small in relation to other mods you will gain alot of area under the curve. The ASP pulley alone is worth maybe 1-2 rwhp in the midrange and maybe 3 rwhp at the top end. The hotshot header nets about 8 rwhp peak gain but with the overall powerband being bumped up from 3500 - 6500 rpm.
Ground wire kits only work on vehicles with poor grounding to begin with, specifically RX7s and other "electronically challenged" vehicles. Alot of the gains associated in the dyno tests could be due to a change in climate or engine operation temps, it's hard to substantuate the claims with hard evidance. Granted you can build the kits for about 35 bucks using 10 or 12 gauge amp wire.