whos the best

[89silverbullet]

who makes the best flowing air filter. I really want to know as far as power gain and longevity

[CumminsPride]

Most of the BHAF are 100k service. Buy a K&N and drive a milllion miles but your engine won't last with it! LOL

[89silverbullet]

100k mile service on a bhaf is bad ass thing to hear but with texas dust almost to good to be true!

[CumminsPride]

With a washable outerwears cover I don't think there is a better option out there for our 1st gens. A NAPA 2790 with an outerwear cover will flow more air than you H1C will ever suck.

[921stgen]

Do you want the best flowing or the best filtering. I use an AEM 5" filter on mine.

[Begle1]

Best flowing filter would be an open pipe.

Best filtering filter would be a piece of sheetmetal.

Most people decide to find a compromise.

[Ace]

Rules of thumb: Better Filtration = Lower Flow. And paper air filters don't mix well with water (in your turbo, that is).

The K&N drop-in replacement flows with the best of them. Only drawback is you have to maintain it properly. That means proper cleaning only when necessary, along with re-oiling with the correct amount of approved oil type. I ran a K&N on my truck for the 1st year I had it with no issues whatsoever, proven by UOAs returned with lower than average Si readings. That comment about K&N causing accelerated wear is true only to the extent that dumb users don't follow the instructions and basically ruin them with improper maintenance.

The stock replacement works well with minimal headaches and represents the best compromise of all aspects including value, filtration and maintenance ease for engines requiring up to 450cfm airflow. I don't know the math equation to compute HP vs. airflow requirement, but my guess would be that's around 300HP. I went back to a stock replacement filter after installing a Filter Minder and determining it met my current airflow requirements.

You need a BHAF, and/or other intake mod upgrades if you're making over 300HP. Don't ask me where the magic 300 number comes from, just a guess. Probably around the time you're going to bigger injectors and turbos. Otherwise, enlarging the intake tube on the stock airbox along with the stock filter is your best bet. You can spend all the coin you like on the Amsoil nanos, AES, yada yada, but IMHO it really ain't worth it unless you've already modded the intake and going big for real.

[dpuckett]

Ace, I have to disagree with you, to a point, about the K&N. When I lived in Calhan and Ft Collins, I had NO trouble whatsoever with the K&N. Moved back to MO, where the soil is a lot loamier, and the dust inherently finer, and I had troubles. Heck, even a little dust gets through the Fleetguard paper element in the course of 20-25K. I could see blue sky through the last 2 K&Ns I had, one brand new from the factory. That tells me they sacrifice filtration for flow.

This thread details my experience with the K&N filter. I have an AFE PG7 in the D350 now, but havent put on enough miles to get a verdict.

Daniel

[Ace]

Undoubtedly, Daniel. See my 1st rule of thumb. That's why I went away from the K&N - didn't really need it. The only question is at what point does the filtration/flow trade-off become more of a liability than an advantage?

That environmental factor you mention is a definite issue I've seen mentioned before. But not a blanket condemnation for K&N some people like to preach. I posted my UOA results on DTR last year showing a 3 Si number (universal average is 7) running the K&N since before I got the truck. So I guess the dust around here is pretty big and they can't be all that bad.

I'm gonna reinstall the K&N one day if I ever make it to a dyno. Then take it out again when I get home.

[89silverbullet]

Best flowing filter would be an open pipe.

Best filtering filter would be a piece of sheetmetal.

Most people decide to find a compromise.

that is probably the funniest thing I have ever read on here. both ways of filtration are involved in turning in your fuel screw
I put my money in to the bhaf. I bought the cover since it is a one time purchase to make the bhaf last longer.

[nooblet]

The outerwear is well worth the money, if nothing else just to keep water off your filter.

Chris

[whereswaldo250]

Will the outerwear's fit on a BHAF from air flo? I would imagine that the napa filter and the air flo filter would be the same dimensions.

[GLHS]

I run an oilless Amsoil 4510. It is harder to see through yet my filter minder doesn't budge compared to the K&N.

[oconnellrb]

Where do you buy the outerwear.

[whereswaldo250]

Here it is

http://www.outerwears.com/