i'm lost right about now... i know its been a long week but yea... i'm a little confused right now. every one is saying the k&n kit is the way to go. i hope no perminent damage has been done to your nose!
It is true that engines can develop more power from cold dense air than from hot rarefied air. Conventionally aspired aircraft engines run like ***** Apes on cold dense air ONCE they are up to normal operating temperature. However, under certain atmospheric conditions that can also generate intake icing which cuts off the air supply in both aircraft and automotive engines, ( the reason for having a method of applying heat to the intake). A KN filter doesn't do any thing different than a stock air cleaner does. A properly functioning air intake system is designed to take in warm air when the engine needs it and switch to external cooler air as the engine comes up to normal operating temperature. There are several conditions in which the engine requires preheated air in order to run properly. Placing a KN (Big Cone) in place of the standard filter arrangement completely defeats that on a carbed engine and does nothing extra for an EFI. In fact, if you don't stick it outside the engine compartment the KN filter will be taking in hotter air than the stock system. In no case will you be getting colder air than the stock design gets. If you will look at the stock design, (carbed or EFI), the intake is external to the engine compartment. The stock intakes are designed to supply as much air as that little stock 302, 351, 360 is capable of gulping. Granted, if you do something that increases the ability to gulp more, then you need to do something to the intake to compensate, but then you need to look at the entire design from intake to exhaust. If a KN actually shows some improvement then I'd suggest that the stock system was not functioning properly. If I look at older engines, the intake and it's associated controls are not functioning for one reason or the other, (usually neglect) or they are no longer in existence on the engine. In that case a KN might be an improvement but it would be cheaper to restore the controls.
I only mentioned the KN Big Cone above, the ones that are circular look alikes to a standard filter or square for a filter box do nothing but
lighten you wallet. They do nothing than a quality less expensive filter does.
So as you can see, my thoughts are with Dave's on this. Show me some dyno testing results that prove the material in a KN filter adds anything to the power of an engine that a properly functioning stock filter system doesn't do and I might become a believer.
That's my .02 on the subject of KN type filters.

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