Hi All... just wanted to mention an anomaly with some K/N filters that I had laying around. THIS IS MORE OF AN OBSERVATION... wonder if anyone else has noticed this too....

1.) Before I did any mods ...I ran the K/N filters on a pretty much stock car--(87 TPI) and didn't see really much improvement over the stocker (Frams) air filters.. thus after the K/N filters got dirty I got lazy and just tossed on a set of OEM (Puralator)... again NO noticable performance difference.

2.) AFTER i performed the following perf upgrades... I originally ran the original OEM air filters and REALLY noticed a difference when I decided to clean the old K/Ns with one of those cleaning kits and tossed them back on the car. TO MY SURPRISE I can actually feel a performance difference with the K/Ns where on a stock car there was NO noticable difference. Upgrades area as follows: Edlebrock Intake, 2800 RPM Stall Converter, Air Foil and 3:42 Posi gears. Again the only difference from the before and after are the K/Ns were cleaned and reinstalled... the Puralator filters when replaced were in "new" condition so they were not clogged.

I could feel an immediate seat of pants difference- feels like about 4-5hp... the tires chirp noticably even under partial off the line throttle..where before the chirp was minimal quiet. Pretty weird. Before I experienced this I always thought that the K/N claims were bullshit... apparantly the "air filter" gains are multiplied a bit if you already have mods in place... possibly???

 

All K&N filters do is let more dirt into your engine. IF you can get a K&N oil filter to seal, they let more dirt into your oil.

 

That's not my experience.. I have owned and daily driven the car for years so I know the stock feel.... The transition from stock (clean) OEM filters and the K/Ns were done on the same tank of gas so the difference I notice can't be the gas... On a stock engine the K/Ns didn't make any difference that I could feel... my point (and purpose of this post) is to mention that AFTER some mods... the switch back to the K/Ns did appear to make a slight difference out of the hole.

 

You're getting better air flow with the K&Ns.
Supply and demand.
There have been many,many,many threads on this subject and I don't believe there has been an absolute conclusion found.