Do Cai Kits Actually Improve Performance?

BIF623 · August 11, 2009

I know this subject has been discussed, debated, etc., etc, forever........but I'm trying to ask in a specific way this time because I never get a definative answer and I'm still on the fence about getting one. My main interest is in gasoline engines (I have the 8.1) but certainly could here some responses concerning diesels. So here it goes..

Does your typical aftermarket cold air intake kit improve the performance of the engine?

(assuming your answer so far is "yes" or "depends") what about the kit is responsible for the performance increase?

A. Is it because it actually pulls in cooler, denser, air? How does it do this, it would appear to be pulling the same air from the same general location as the stock air box?

B. Does it improve performance because the filters allow more air flow, either through a larger surface area of the cone shaped elements, or the filter material itself flows more air, or both?

C. Does it improve performance because the intake tube that replaces the stock one, flows the air in a more smooth, linear pattern? As long as enough air is getting to the TB, does that really matter?

D. Is it a combination of all of the above?

I ask these not to stir up an argument, but because I really don't know. I'll hear one smart guy say "the stock GM air intakes flow as much as needed and more air doesn't make any more power....." then I'll hear another guy say it does.

Does more air available, make more power? Do aftermarket CAI's flow more air? Do aftermarket CAI's flow cooler air?

Thanks for any input.

Stevens03 · August 12, 2009

I have no proof other than butt dyno. I've had one on almost every truck I've owned and all have made some sort of improvement.

For your year of truck, I'd recommend S&B intake or Volant because they are true cold air intakes.

Thats my opinion and I'm sticking to it.

Zembonez · August 12, 2009

NO.

Although is appears to be scientifically possible, I've not seen any proof that they do anything but make more noise.

Matt_ · August 12, 2009

Some kits make you "feel" like there's an improvement because they change the sound of the engine and you can actually hear the airflow, as opposed to the stock intake which quiets everything down.

My main reason for changing the intake was always to get a re-usable filter... and maybe some bling under the hood

If there is any improvement, it will only be at wide open throttle when absolute maximum airflow is required... but that's debatable because this would assume that the OEM setup would be restrictive.... which would be a stupid design on the OEM's part.

Stevens03 · August 12, 2009

My butt dyno does not lie

I've seen/experienced more than just the "feel" from the noise

Matt_ · August 12, 2009

and my truck "feels" quicker after i wash it... but im not sure how much HP that actually adds. Maybe its because of the reduced friction when its nice and clean?

Wingnut · August 12, 2009

NO.

Although is appears to be scientifically possible, I've not seen any proof that they do anything but make more noise.

Pretty much my take.

The only place they add any sort of measurable HP is at the higher RPM levels. Like REALLY high RPM levels. The kind of levels you spend .0004% of your driving time at.

Consensus also seems to be that once you do other "breathing" mods, they can actually help more. But I don't mean a catback. I mean intake manifold and headers.

Stevens03 · August 12, 2009

and my truck "feels" quicker after i wash it... but im not sure how much HP that actually adds. Maybe its because of the reduced friction when its nice and clean?

Oh it's gonna be like that now... Believe what you want.

Edit:

I'm only going to explain myself once... then move on. On one truck, there was clearly an increase of mileage after the air intake was installed, on most of my other trucks, they've improved throttle response as in held higher gears longer while climbing hills, or was able to hold speeds on the highway up grades without stepping down on the throttle, where before (stock intake) I had to step on the gas to maintain speed. I could tell a difference when towing heavy loads... so I've been able to justify the mod.

I'm not saying OMG they are worth $400 and OMG you get so much power from them, I'm saying they do make a difference whether you want to believe it or not. That's been my experience with them and why Its one of my first mods.

Your entitled to your opinion.

Feel free to attack all you like

Matt_ · August 12, 2009

and my truck "feels" quicker after i wash it... but im not sure how much HP that actually adds. Maybe its because of the reduced friction when its nice and clean?

Oh it's gonna be like that now... Believe what you want.

66nova · August 12, 2009

Basically, NO. Not any real difference, but if you are looking for every last pony and you are looking for a little more sound. Go for it. The ONLY time they are going to help is at W.O.T.

Here is a link for a HP comparison between a number of differnt intakes/filters vs stock. The best one only netted a 8 more peak hp.

CLICK HERE

They do sound a lot meaner with an intake.

Zembonez · August 12, 2009

Basically, NO. Not any real difference, but if you are looking for every last pony and you are looking for a little more sound. Go for it. The ONLY time they are going to help is at W.O.T.

Here is a link for a HP comparison between a number of differnt intakes/filters vs stock. The best one only netted a 8 more peak hp.

CLICK HERE

They do sound a lot meaner with an intake.

I'll agree that the sound is cool...

and my truck "feels" quicker after i wash it...

^^^ That's funny right there.

2COR517 · August 12, 2009

I'm actually surprised by the consensus here, which I agree with. I only had one CAI, that was on an 89 K1500 w/305.

No doubt it did provide cooler air vs. the stock setup. I installed it the same time as a Gibson 3" cat back. Can't really say I ever noticed a difference, except sound at the tailpipe. That thing sounded like a big block.

I cannot believe that a CAI on a 96 or newer is going to make much, if any difference. The only possible exception is at WOT, high RPMs as already mentioned. As for increased noise, they absolutely do that. Couldn't hear yourself think in the 89 once you got past half throttle.

I will never buy another one. For the same money, you can get a custom tune. Those will pass the Butt Dyno, and real dyno tests every day. And offer better MPG to boot.

Spurshot · August 12, 2009

Wow! I'm surprised at the number of guys that say they don't do much. Given the popularity of this mod, I'd have guessed about everyone thought their "butt dyno" said mucho more horsepressure. Not that I'd believe it all.

The first real data I've seen on an aftermarket air cleaner was the Volante thread that the guy was having problems with recently. He went thru the trouble of collecting at least one parameter I thought was revealing about the air flow capacity of the stock air cleaner vs. the Volante. He showed us MAP sensor numbers. Here is a quote from his thread. "... in the WOT logs, the MAP for both is the same... 12.xx min to 70.x max ..." I'm not sure how that data was collected, but it seems to say there's no difference between the Volante with the massive filter and the stock setup...at least in terms of manifold pressure. That actually surprised me. I was hoping/expecting some small improvement in manifold pressure. I believe both pickup the air in the same location and inlet temps should be same. As they say: "the data is the data". So far, nothing has convinced me to part with $300-400 for one of these things.

I'd like to see similar data on the triangular shaped CAI with the two flex ducts that go on either side of the radiator.

dansk · August 12, 2009

I don't want to speak for Justin at Blackbear but I asked him about CAI's when he did my tune. His opinions are based on numbers from real dyno's and he said that they don't really do anything. Exhaust yes, CAI no.

Spurshot · August 12, 2009

Yeah, I looked at his dyno data on the link someone provided above. Nothing in there that would make you want to run out and spend the bucks. The differences could even be scatter or test setup differences. Don't know if it was done with the hood open or closed, or whether there was a industrial fan directed at the front of the truck to simulate road speed. I sent a PM to Jenna asking about the hood open/closed.