I have a 2001 C5 and recently purchased a dual 7.5in cone type air filter to replace the stock air intake. I made the purchase mainly for looks. But the product description for the new air intake says that HP can increase by as much as 18 HP using the new air intake compared to the stock intake.

My question is how could the HP possibly increase this much and if it can't how can the manufacture of the custom air intake make this claim?

Seems to me that the engine will draw in the same volume of air w/o boost.

 

You can see gains from an intake. Some more than others. The twin cone intakes are probably one of the lesser performers, while Vararam and Callaway Honker are probably towards the top.

I was running 107mph 1/4 mile traps bone stock, added headers and trapped 109, finally adding Vararam+tune got me up to 115mph. I'm sure the tune was a big part of it, but the intake definitely gained.

 

An important factor in an intake setup is how smooth the flow of air is. Not just a low impedance filter. By removing the accordion ducting and other restrictions, air is less turbulent and more can make it into the cylinder before the valve closes. It's just a way of getting a little denser charge. Very little though. A well designed intake will have a low restriction filter, and a shape that increases velocity of the air to the throttle. Other work to and past the throttle is need to make real use of it though.

 

Your PCM has firmware installed that measures the incoming air and it was made using the accordion duct, when you change to a smooth coupler you are moving more air but at a slower velocity. A cylinder will only hold so much air without being supercharged/turbocharged so you will not put anymore air into the cylinder. The dual cone filter will still pick up the heated engine bay heat as a regular filter so you may experience little or no change to your acceleration but the noise factor will increase. The only way to increase the density of the air is by getting colder/denser outside air to the engine. That is the principle of the Calloway or Veraram intakes. Even they will not make the best use of colder more dense air without changes to the PCM. However, the PCM has about 512K of code but only 90K is programmable The key to gaining HP/TQ is to maximize the efficiency of the air/gas mixture as it goes through the engine. HTH

 

More snake oil. Nobody polices these manufacturers so they can claim most anything, you going to sue them??

 

Thanks to all who replied. My takeaway from the responses is pretty much as I thought, should not expect a significant HP increase from a simple air intake change. Cannot defy laws of physics. Either need to have more air or true colder/more dense air into the cylinder to increase the power. The intake still looks cool (no pun intended) and should be a little more efficient providing less turbulent air flow. Wish product vendors wouldn't try to over-sell performance in advertisements. The automotive equivalent of miricale weight loss products.

 

18HP on a very heavily modified car with a horribly clogged air filter?
If they don't oversell, they won't sell much. Look for dyno results from claims like that, what type of motor, etc.

 

In and of itself, the gains are next to nothing and thats where most people base thier information.
However, with a combined set of mods, an intake can increase airflow and volume, hence the air pump analogy... so, yes, they actually do produce gains but are more prevalent upon the addition of other mods

 

I bought my 02 Z06 with the dual-cone CAI already installed. I've been curious about HP gains myself, but have yet to get it dyno'd. Probably the only way I could determine actual gains is to get that done and then compare my HP numbers to "average" stock HP.

 

Every 3 to 5 years, any C5 owner should dismantle the radiator shrouds and clean out the debris from your radiator. You will be amazed at the crud that is in there! Runs cooler, too (all things considered).

When you have done that, you are 75% of the way to a Vararam installation. Great installation video on Youtube (see link on Vararam site). Just add an air gun to spritz the radiator and you are all the way there.

Cheap thrills :-)

 

On a 350 hp engine, an 18 hp increase due to changing the air intake equates to about a 5% increase. If one assumes the stock intake presents 95% or less of ambient pressure at WOT at peak hp rpm then theoretically a better performing intake could get up to about an 18 hp increase. I know my engine isn't seeing full ambient pressure with the intake I have now.

 

The way to increase HP, in a stock engine, is cooler, more dense air and/or a tune which maximizes the timing/mixture/duration of the engine.

A cylinder can only hold so much volume and that is with a mix of air and fuel which is only in grams/cylinder, yet the intake manifold holds quarts of air and the intake runners can only allow as much air mass as the runner size. Increasing MAF, smooth air bridge or a larger TB cannot make the runners of cylinders flow or pack in more volume then their size is.

 

Actually there are only like 3 true CAIs - Honker, Vararram and I think Breathless Perf. The rest, like Haltech, Blackwing etc still use ambient air from engine bay. Which may be better that stock, I don't really know. I just know when I installed the VR, is showed no difference on the dyno, but I did pick up 3 -4 mph on the back stretch at VIR. HTH

 

Agree that increasing air density going into the cylinders is the way to increase HP.

Also agree that the volumes you noted are fixed, but that isn’t the point.

The point is increasing air density – more specifically how the intake tract can decrease that density and hence power.

We know that we control engine power through the throttle body. The throttle body is nothing more than a variable intake tract restriction. We can feel and hear its effect on the engine. We can also see its effect on engine vacuum or Manifold Air Pressure (MAP).

An undersized throttle body at WOT will flow like a properly sized one that isn’t fully opened. The rest of the intake tract can have the same effect.

A well designed engine like the LS1 will be in the neighborhood of 100% Volumetric Efficiency (VE) at peak HP operating conditions, closer to or even over 100% at peak torque. At 100% VE percentage changes in pressure will have a 1:1 effect on percentage changes in airflow.

If you can read your engine’s MAP sensor data you can get a feel for how much power and torque you may be leaving on the table. With the key in the run position but engine not started see what the MAP sensor is reporting. It should be close to 100 kPa. Then while recording MAP sensor data take the car out and get it to WOT and look at the MAP data. It will be a little bit less than the non-running level, unless of course your engine is boosted or has a VERY effective ram air setup. The difference is going to be close to the % of power being choked by the intake tract. It’s theoretically possible to eliminate most of that pressure loss. It is that potential to eliminate most of that pressure loss that an aftermarket intake may (or may not) provide you.

My car isn’t stock. I’m pretty darn sure it has a cam in it. I know it has long-tube headers. I know it doesn’t have cats. I know it has a loud aftermarket exhaust. I know it has the Weiand/Lingenfelter intake manifold. I know it has the zip-tie air intake mod. And I know my MAP sensor is telling me I’ve got airflow restrictions costing me over 5% MAP.

If my dyno run this summer was correct, and assuming a 20% automatic transmission drivetrain loss, my engine is putting out close to 480 HP. If I could eliminate all of the MAP loss I should be getting over 500 HP out of my engine.

So the point is a restrictive air intake tract is like a less then fully opened throttle body. It’s sort of like putting a brick under your accelerator pedal. Whether or not anyone’s car, stock or not stock, can benefit from any aftermarket air intake I can’t tell you. What I can tell you is that there is a way to pretty well quantify what’s being left on the table.

 

Some of which can be attributed to pulling in outside the engine bay and cooler/denser air and some of which can probably be attributed to a ram air effect.

 

Finally, a question I can answer, since it requires only english , and not mechanical skills..

A lawyer would point to the phrase, "can increase up to" Quite different from "will increase". Jerry Jones "can" sign over the Dallas cowboys to me, anytime he wants. Will he do that is another question.

As another poster mentioned, without a starting point, measurements mean little. Tough to beat a modern fuel efficient factory design without changing the tradeoffs or , the more common road to improvement, more money in the part.

 

I know that the thread is several months old but the following information in the link provided may be of help. With that said I'll introduce this with a quick response:

Hmmm... nice postulate but it doesn't work. The stock system on a C5 is nowhere near optimized, and thus it is not all that difficult to beat. Enoniam is correct, and my thought is that he is simply trying to point to the fact that there is H.P. to be recouped from being able to reduce the losses from a restrictive system. The caveat is that there is no way that he, nor anyone else, can guarantee that every system will give "x" amount of increase on every C5 under every condition. No one can. What we can say is that there are solutions that have been dynoed and shown to improve H.P. in comparison to the stock system on different C5's with differing amounts of work done to them; from totally stock to seriously wild. Why? Because the stock system leaves a lot on the table. It's horribly restrictive in comparison to even what the stock TB can flow. Increasing the CFM capabilities of the Air Intake, MAF, Bridge and even the TB show some very nice CFM gains; gains that have been shown to increase H.P.

Check this thread out for further quantified, independent test data...
https://www.corvetteforum.com/forums...fications.html

 

You can get a used Vararam for $200... put it on and if you aren't satisfied with the results... take it off and sell it to the next sucker for $200... I bought one and it's STAYING on my car!

 

I have two C5's - one has a Vararam and one has the dual cones. Having seen the difference, I just bought another Vararam and will have a set of cones for sale in the near future - once I get the time to install the VR.

 

Aother benefit of a cold air intake is that it helps keep intake temps low. At higher air intake temps the computer is going to pull timing, which is going to cost horsepower.