I read the thread on "bad gas mileage" and I guess we're all in the same club. Has anyone tried one of the "performance filter kits"? I see some people stating improved power and mileage but I am VERY skeptical.. If you go to K&N website it stated 17.55 HP gain showing the dyno sheet.

Just looking for some real work feedback.

thanks

 

I ran a KN Filter on my 94 Suburban from day one. Less restricted air flow is why they will improve power. Internal compustion engine is an air pump and more air is better. You should clean them more often than you would change out a paper filter though and be more religious if you run in dirty dusty areas. I can't vouch for gas mileage improvements as it seemed the 94 4X4 got 10 mpg in any direction, towing, climbing or descending. But it would pull the a$$ out of an elephant going the other direction. And, KN replaced it under warranty after 13 years and 250K miles when it showed deterioration in the cloth. Haven't yet put one on the 2010 but plan to.

 

It will not do anything on a motor that is not modified. The factory set up already takes in all the air it can use. Just because the air filter is bigger the throttle body, intake runners and passages in the heads are the same. It will make more noise (sucking sound) which along with the hype makes people believe they have more power. Also the air flow meter is just going to adjust the fuel to keep the mixture at 14.7 :1.

 

And to add to that, notice where the hp increase occurs. The last time I looked, it was up around 5,000 rpm. While that might help w/ my old Corvette, I just don't see 5 grand in the Tahoe.

Check out Blackbear if you want some more grunt in areas where you can use it.

 

all agreed the HP improvements is so high in the RPM band with these intake kits that it is pretty much useless in this truck. I put a drop in K&N filter into my vehicles simply because I don't want to have to throw away used filters every year. I buy into the fact that it reduces trash in the landfill more than anything else.

 

Like others, no noticable performance gain. I bought it for more induction noise and slightly better throttle response.

Agreed, that supporting mods are needed to have a noticable effect.

 

well, there is two different things on K&N. Cold air filter kit ( comes with different intake pipe and housing) or just simple K&N filter.
I got first option with hi performance royal purple motor oil and am getting better gas millage and more power as well. But, do not expect huge different

 

Once used a K&N drop in filter on my Expedition. Other than an increase in induction noice, I only noticed a slight ease as to which the vehicle increased speed, but this is subjective. I stopped using K&N filters all together when after cleaning one, and re-oiling it, I apparently used too much oil, the excess oil fouled up my MAF sensor.

 

Seems that its more trouble (and $$) than it's worth.. Agree on they HP and dyno sheet, but it does seem that you get a decent increase in torque through the RPM range.. But again, really not important 90% of the time for me..

 

So what is the limiting factor in the factory intake setup? Does the air temp in a "cold" air intake actually make a difference in engine efficiency?