Okay, I have been a huge K&N user for the last three vehicles I have owned. I now have a 2005 GMC Sierra 1500HD 6.0L. I did a cat back exhaust improvement and Hypertech Power Programmer to it. I've had it for under a month now and besides cosmetics, the last improvement I would like to do before saving up for further improvements is the intake.

It used to be that other brands were poorly constructed, but now it seems everyone has met or exceeded the performance of the K&N systems, so I would like to know what everyone thinks is the best one out there and why?

Thanks

I vote for aFe, it's the best I've found. MrQuadrasteer will have his review soon.

I am not too familiar with the gas mototrs, but my experience with the diesel, is that the stock system is the best intake there is, from a filtration point of view. The stock element has nearly 0 pressure drop, and filters more efficiently than ANY of the aftermarkets. That was considering 700-900 max cfm. Clearly the gasser is less than that, 400-600 maybe.

Now the concept of "cold air" is a valid one. If it is an intake system that indeed isolates air intake from out side the engine compartment, you can lower IAT by 50 degrees on a hot day, compared to engine compt air, and that's power. But you lose some filtering capapbil;ity, important if you are in dusty areas. It dirties up the oil quicker in addition to additional engine wear.

Just some things to ponder.

Welcome to the Club, Joe

I've been running a Volant for a little over a year now. I've been happy with it. It's made decently, wasn't too hard to install. I always liked the sound it makes, and I think it made a little a difference in performance.

But- I just got me an aFe intake, and I'm dying to get it installed !!!! This thing looks way-sweet. It's got a HUGE cone filter compared to all the others I've seen, but in particular, the neck is easily twice as big as the Volant's.

Then, to neck the huge filter down to the tube size, it has a machined aluminum venturi piece. I think this will be the feature to really set it apart. The venturi should increase the air speed inside the tube and, in theory, create a positive air pressure. Yup, a mild (very mild !!) supercharging effect.

I'll have dyno reports on all three intakes- stock, Volant and aFe. And the dyno don't lie !!

Mike, I've read a bunch of stuff on this topic, and there's a lot of guys that feel your way, a lot that think the opposite. I'm a bit in between, I haven't done any HARD testing or anything. But I lean towards the aftermarket systems.

Comparing diesel vs. gas is a bit of a problem, tho. Not being super-familiar with the oil burners, I'll say this from the gas-side:

I think the stock filters leave a bit to be desired. While I'll agree a dry paper filter works good with little drawbacks, I think an wet-filter filters WAY better, albeit with a couple drawbacks- if you over-oil, it'll dirty up your maf sensor and make you run crappy (but a quick, free fix to clean) and over-oiling reduces flow.

But more important is where the stock filter pulls it's air and thru what size opening and where the a/m units pull their air and how.

I was blown away to see that GM feels the 6-Os only need about a 2sqin hole in the airbox to breathe thru !!!! The Volant offers up a 3" diameter hole on bottom and about 5~6sqin on the fender side opening. Definitely has to help. The aFe looks as it'll offer totally unrestricted flow AND has provision to be a hood ram-air, which, to me, is so much better than a bumper ram air that I never considered the latter. Way too much chance for crap to go in, water especially, plus that's not the best air- it's where the car in front of you will be exhausting, right ?? So you're getting dirty hot air ??? Nah, ram-air belongs on the hood

Holy crap !!! A little too much coffee this morning, ya think ?!!!?

This message has been edited. Last edited by: MrQuadrasteer,

...you saying the intake pipe is 2 sq in? I don't have to do any testing to know that is very restrictive, that's air moving at 320 mph (assuming 400 cfm) at full throttle! You must be mistaken

No, I meant the opening in the airbox that the engine breathes thru.

I'll go edit that so it makes more sense

still, any restriction of that sort would be detrimental. I'd love to see a pic. What is the area of the stock element?

Exactly. The factory thinks the engine can breathe thru this itty bitty hole, but the aftermarket gives you basically unlimited room to breathe.

And gives you that cool intake honk !!

I have pics- lemme get them together

This has been truly enlightening. Thanks for all of the responses. It looks like the aFe is the way to go, or should I wait for Mr. Quadrasteers test results? I really don't want to create a maintenance nightmare for myself. While I have performed elementary mods to my previous vehicles, I just wanted to add additional horsepower and gas savings without having to to tune the vehicle every month. Having qualified my position, what other performance enhancement can anyone suggest without going the route of supercharging, NOS, or any of the really involved mods. To further qualify my question, I plan in the future to tow a trailer later, but am not going to race or do the Baja races anytime soon. I'll make trips to the desert and river from time to time and do some camping. I've done light to medium off roading, but no hard rock climbing or river crossings. Thanks for all of your info in advance.

Joey

2005 GMC Sierra 1500HD 6.0L, 4X4 Quad Cab Hypertech Power Programmer III, Magnaflow muffler, 3" cat back exhaust, ARE LSII series Tonneau, back up camera with visor mounted screen (a Godsend for backing up) with future mods to be posted when done, bought the truck 4/09/05!

Let's go Mr Q. I need to see where there is a restriction of 2 in sq, that would be like a 1.5" diameter conduit. I just can't fathom it.

My intake has about a 3.5" avg ID, or 35-40 sq in. And about 400 sq in of stock filter element. Much has been researched on it, and no gain is possible with it in the under 400 HP class.

The filtration of ALL the aftermarket filters have proven innefficient compare to the stock filter in the D'max, which may be the same that everyone has. If interested, I can find the study for you. The paper element is the best there is, even when it gets dirty. There is a lot of hype in this market, and lot of money being spent on hype.

Eric,

Supposedly, Volant redesigned their CAI recently. Is your Volant the new or old model?

I'm eager to see how the tests pan out.

-Pete

Michael, aFe has a Pro-Guard 7 made for diesels that is 7 layers instead of 4 in most washable permanent air filters. No one has any thing like it. You can read more at, http://mrtruck.net/proguard7.htm Not trying to argue, paper does a good job of filtering air but it also restricts the air to do it. aFe's Pro-GUARD 7 has the same filtration stats as factory paper filters, but allows more air flow and is reusable.

Joe, if you can, I'd wait for a good comparison before laying out the money. I have a lot of confidence in the aFe, especially in light of the Volant redesign, but ultimately... the numbers don't lie !!!

For awesome gains out of our trucks, NOTHING beats a custom tune by Wester's Garage. Unquestionably the best bang for the buck mod available. A good intake, electric fans (your 05 should have them), a good exhaust, flow-matched injectors. All of those items will boost power AND economy, provided you keep your foot out of it !!

Prophet, mine's the old design.


Mike, I still think you're misunderstanding what I meant. I was simply talking about the actual opening in the box where air enters, not the tube size or any specific restriction.

However, (and I knew this, didn't mean to be taken so literally !!) the actual opening(s) I was referring to add up to about 15sqin. Yes, a lot more than 2, but still small by performance standards.

Your filter has 400sqin of surface area ?!!? Mines has 114sqin of filtering surface. Gas vs. diesel ??

I think I mentioned, I haven't been up under a D-Max (or any other diesel for that matter), but I'm sure they have very different requirements for air. I'm not sure if we can make good comparisons here, Mike.

And as far as factory filters being the best filters available, I doubt it. Maybe in the diesel world, but what I see is a cheap filter, made for profit over quality.

You think the OEM manufacturers spend the same time or money developing and designing an intake or filter as much as a company that specializes in that line ?? I'm sure some design criteria goes into it, but they're looking at profit margins, not what's the best filter they can give the consumer. What fits, what's quiet, and what's cheap...

But, like I said, I have 0% diesel experience, so none of this may apply there

Anyway, my .02

The top hole is about 2" tall, bottom hole is about 1.5" tall.

Thanks for the pics and clarifications.

The area of the element takes into account that it is pleated. Maybe you weren't considering that. If it was unfolded, you could use it as a blanket.

Yes, it is a different design than the diesel.

Are those both intake openings?