Robert Perkins

I have been reading here that a CAI can give 10 to 15 hp increase, is this true. I have a 2009 with the NPP exhaust all stock with 29K miles. I am having it Dyno tuned this spring and wanted to install the CAI before tune. Is it really worth the money for the CAI and what brands do you all recommend and what has been your experience. Thanks for all your input.

Dcasole

Oh boy , going to open up a can of worms here but here goes ....

I put on a VARARAM , I chose it because of HOXXOH results ... he is very knowledgeable and has the time slips to prove that the Vararam made his car faster ( plus a great driver mod lol)

It is also one of the few intakes that will not generate CEL , most think the CEL is because of a lean condition but it is fact caused by turbulent air flowing over the sensor causing inaccurate readings and surging . This is the reason why the factory LS3 airbridge has a Heimholtz resonator attached to it
Now does a CAI add 20 hp ... no way .... especially if you have a ZO6 or LS3 air box as they both breath pretty good and with a stock motor you will never need more ... but what the VARARAM does do and I have logged these results is provide lower intake air temps resulting in the ECM not pulling timing allowing your car with all other things being equal to make more power than a similar car without a CAI

Is it made well ... no not for the money , can you fix the problems with it as far as the filter and sealing issues, absolutly. I re glued the foam , re bent the clamps on both sides and now have a nice tight seal . I also now have no problems taking it apart to re-oil my filter . Do you need a tune ... no as the ECM has more than enough built into the tables to compensate..

Just my 2 cents ....

Davev

Dano523

The short answer is NO!!!!

What happens when the engine is pulling it hot air, is that the timing is retarded, and you lose HP instead. So what the CAI is claiming, is that is can save you this amount of lose of HP, isntead of the engine pulling in that hot of air instead.

So here is the standard AIt verse timing pulls,



The second problem with a lot of CAI systems, is they don't actually pull in cold air, but instead just pull in the same air as the stock air box location instead.

Simply put, the air intake system on the vet, is already pulling in more air that the motor needs, so increasing the air flow into the engine via a different filter system gets you nothing.

So if the cold air system is going to work, it has to pull air from outside the engine bay to start with. Now the next item on the list, when it pulls this air in, it still needs to do it smoothly across the MAF, or it going to cause nothing but problems (surging). Hence some of the true cold air systems cause problems with the air flow across the MAF, and a tuner has to try to solve this problem with the tune next.


Lastly, is where you pulling the cold are in from, and systems like the Vararam since the inlet is so low in the car nose when driving through deep enough of a water puddle, can suck water into the engine to hydro lock destroy the motor isntead.

dmoneychris

I have to disagree w/the 'NO' answer. If the air entering the engine is cooler than the hot engine bay & there is more of it, I would have to agree that a CAI will increase power & efficiency. Halltech is your answer. It separates the hot engine compartment air from the air entering the air filter.

( http://www.halltechsystems.com/Hallt...-p/kbmf108.htm )

Dcasole

Well now you base your answer on what data....??

it does make power , because the ITA is cooler allowing the ecm to not pull timing ......so yes it makes power but not anymore than the engine would produce on its own with the same ITA ...

also the Halltech is one of the CAI that reports surging

Dave

Boomer111

I experienced surging with the Vararam took it off for the reason Dano explained.

Now the tuner tried to tune out the surging but was unable to. It was present with a steady throttle position and slight but nevertheless disturbing for me.

The 427 cu Z06 uses the same filter as the LS3. Air isn't the problem.

In my experience the only viable use is at the strip. For a DD no suggested.

I am back to a stock set up.

Dcasole

Boom, we're u using version 1 or version 2 , the one listed for the LS3 . The reason why I ask is because Vararam supposedly fixed the surging with the later version that does not use the factory accordion hoses

I have the later version on my car and do not get any surging at all

Dave

outhouse

Factually YES


The confusion displayed by so many here, is that many so called CAI are not a TRUE CAI.


Calloway Honker is a true CAI bringing outside engine bay air in


YOU WILL see CAI like my K&N claim high numbers but that is simply because the hood was open during dyno pulls. THIS does not recreate real world driving conditions.


SO if you want gains look for a quality unit that actually draws outside air in.

Dcasole

Factually the answer is no ..... a cold air intake will not add any power .... even if its pulling cold air in from outside the engine bay .it's not like adding a cam or headers ....that's adding power

What it will do is allow your ecm not to pull timing because of high intake air temps, see the graph above posted by Dano ,

the ECM will pull some serious timing when the ITA'S are high which results in a corresponding loss of horsepower.....

So all things being equal, on a 32 degree day ... maybe 50 degrees under the hood , the motor is going to make the same horsepower with or without CAI ..........the ECM is not pulling any timing at this temp.

Now change the scenario, 80 degree day , 110 under the hood , you are using a true cold air intake like a Vararam, the sensor sees 80 degrees and not 110 hence it does not pull as much timing as it would if the sensor was seeing the 110 under the hood temps .

Dave

outhouse

Dave there is no arguing this, cooler outside air adds more HP then hot engine bay air. this is a fact and not up for debate.


Factually EVERY true CAI adds HP when dynod.


NO WHERE will you find a source or thread that states they added a true CAI and their HP numbers stayed the same.


The FACTUAL HP gains are not from better breathing air cleaners which FACTUALLY have showed negative gains by some and only the manufacturer stating extreme gains.



Actual numbers are much different then 30 degrees.

Dirk Miller

I put a Calloway Honker on my '08 C6 with NPP about 7 years ago. I had not expected any real increase in power but since I got a good deal on this, I had it installed. Sure enough no obvious difference. Then had the car's computer mapped for roadracing. Experienced a bit of a boost but nothing too exciting. Within a few months I installed a C6 ZO6 exhaust manifold, cats and H pipe that I picked up used for $400. The difference was amazing plus the sound turns heads. Actual rear wheel hp on a DynoJet and Mustang are now the following: 417 and 424. Take note California folks; this set up has passed smog twice for me now. FYI: tonight on our C.F., I see a set of these for sale in southern ca. for $300.
My take on a CAI is that any additional air this can bring into our motor is cancelled out by too much restriction. Yet if a person adds a better exhaust system, the air releases better and the power can be clearly enhanced.

HOXXOH

OK, so here we go again. My name is Tom and there's a reason some friends call me a Doubting Thomas. I tend to question many things, including rules of thumb, old wives tales, and especially advertising claims. Of the things that I have an opportunity and capability to check for myself, I take a fairly scientific approach and document the results. I've been an experimenter from a very early age and it has served me well in both business and personal life. My engineering background has included air control systems, metal fabrication, and aerospace. Those things are part of why I've managed several drag racing records in the past and currently my '08 DD is at the top of the list here for LS3 boltons.

When I first started racing my Vette and went past the bone stock stage, it was easy to see that getting air in was a bigger priority to getting it out. The toggle bolt mod was the first attempt, but they fell out, so I devised a better way to prop open the shroud. I later did a back-to-back test on a friend's car and verified a .18 second improvement. See https://www.corvetteforum.com/forums...post1586336347 That's pretty clear evidence that colder air is beneficial.

Now, regarding the Vararam and any other true CAI that pulls air directly into an opening that is located outside the engine compartment. There will be a HP increase any time the air reaching the TB is cooler than the air coming from a source under the hood. It's not simply due to timing not being retarded, but that colder air is denser and therefore contains more oxygen. Here's a handy calculator to plug in atmospheric conditions, which will tell you the percentage of HP relative to SAE standard conditions. http://wahiduddin.net/calc/calc_da_rh.htm In Decasole's post using the example of 32 degrees ambient and 50 under the hood, if we can get the 32 degree air at the TB, we can gain 2.2% more power than the 50 degree air.

As we investigate further, we will find that the larger amount of turns and tighter radii the air must take, the lower the velocity that will be possible. Without getting deep into this subject, just remember that air travels in straight lines easier than around corners. Again, you can refer to the propped shroud link and see that it creates a straighter line to the TB.

Next we look at pressure, since it also affects power. A mere .10" Hg increase in air pressure can increase power by 1/2%. Even though a NA engine draws air into the combustion chamber by vacuum on the intake stroke, it's aided by the velocity and pressure of the incoming airflow. Anything we can do to increase the pressure of the incoming air will increase power. Since the car movement creates high and low pressure areas of varying intensities by design features, the location and size of the inlet becomes a factor. For simplicity sake, the additional air pressure on the front of the car at 100 MPH is equivalent to .37" Hg. If we could get that pressure at the TB we'd have a 1.5% power increase. Unfortunately for this problem, the airflow doesn't make a direct hit anywhere on the car, but it comes closest in the grille opening. The opening on the Vararam is located just behind the grille and it's about 24 square inches. Because the TB is slightly over 10 square inches in free area and the Vararam contains more volume than a straight tube, it becomes a holding tank of sorts for the excess pressure that is available. As the car speed increases the pressure goes up, however as the engine speed increases the pressure drops. Even if the average pressure only adds 1% extra power beyond what the cooler air does, that still beats zero.

Boomer111

First version.

The quality was lacking too and a real pain to check filter all the time for fitment issues. I grew tired of skirting the emission laws and aftermarket product problems. back to stock other than the Corsa Sports and the differential. The 4:10 is my best mod along with the tinted windows and non RF tires. Then their is the suspension changes too. I guess labeling one mod as the best is unfair.

damascus1986

i went with the halltech that does not need to be tuned for installation according to them. I was previously tuned with headers and xpipe. when i added the intake and went back for a retune tune said he had to adjust my fuel trims by 6%. I only experienced surging the first day i put the intake on and still had my shroud propped, once i closed it it was back to normal. installation was very easy.

i would say gaining 15-20 with just a intake is a little more then id expect
either way after reading the forums here my decision basically came down to halltech or vararam.

sfrank2886

Halltech, LS3 with no tune and NO Surging. Also no need to cut the shroud like the Vararam. That was a determining factor for me. Both have proven to increase power with added tune and addition of better flowing exhaust which is my plan next.

Timothy Barth

If it was that easy to get 10 to 15 more horses by CAI I would think GM would already have went this route.

sfrank2886

Not necessarily true. They intentially de-tuned the throttle response so GM is not always looking for max performance or HP particularly on base models.

MTPZ06

Halltech MF103 on my C6Z for many years...stock tune, zero surging ever. HP gains...who knows? Improved throttle response was certainly noticeable.

Midnight08

I love when people sight this argument - missing the bigger picture. GM has to think about all the different conditions the car could be driven in - including serious rain. Serious rain can be a challenge for the real CAIs, as others have already suggested. And, if you think about how many series the Corvettes get raced in, especially road series, like the 24 Hours of Rolex, starting tomorrow, air intake solutions from GM have to take bad conditions seriously.

Bottom line - unless you really are getting cooler air, little chance of benefit, and as a practical matter, as another user pointed out, opening up the back end of things gives the engine a reason to pull in more air + fuel. More air and fuel is a good combo for getting more power.

grayline

Haltech killer Bee is what I have and I have never Dynoed I can feel and hear a difference. IT DOES SOMETHING......