Hey all,

I just bought a K&N air filter from a guy, but did not realize that it was the small one (~4-5" tall). Would it be acceptable to use this, or would it create a bottleneck? I'm just not sure if the air flow would be higher than that of the afm. Should I just buy that larger filter? Suggestions appreciated.

 

my .02 is that a larger filter will work better(i.e made from right material)larger surface area allows more flow....just my .02....

 

jarrod,

Yes, I was thinking the same thing. But, if the flow through the filter is greater than the flow through the inlet, it would be okay. Anyone know?

 

it all depends on the flow ratings, the filter i have is rated to around 800HP worth of air - good for me aiming at 500ish

 

bigger means more HP but to a certain extent. remember the intake hose (the piping to the engine) has a cross section diameter of X amount and that determines the amount of volume of air that it can flow through at a given time.

 

That size should be good for 200-275bhp, depending on whether it's closer to 4 or 5" in length. Unless it is actually causing a noticeable restriction, the smaller filter is fine, and the only advantage in a larger filter would be that it filters more air which increases the service life of the filter. If it is causing a noticeable restriction, then you will need a longer filter.

 

I use to run a smallish air filter - K&N universal PN-RU3120 which was like 6" tall, 4" diameter bottom, 2" diameter top, taper, 10-degree offset.&nbsp Yes, it was a dinky filter.&nbsp With no boost control, my turbo would barely hit 9psi.&nbsp I swapped it out for those typical "Funnel II" (R.S. Akimoto rip-off) type air filters, and my boost immediately hit 12psi.



-Ted