I disagree, although you are right about the computer adapting to new airflow, but that is where the 7 hp's comes from. We are talking about getting a substantial gain in hp's here not what the engine can adapt to and give us. I belive my logic to be exactly correct, especially considering my brother who attended Wyotech and TSTC, has taught me these things. Although there is a lot of hype from the aftermarket companies claiming huge gains in power, torque and even fuel economy, the reality of the situation is that cold air/ air intakes rarely provide a decent return on your investment. Lets go over why. OEM's know how much air a vehicle requires. They’ve done the research, test, spent the money, and they typically provide sufficient room for abnormalities when it comes to engine operation. Therefore when designing an intake system for a production vehicle they will provide ample room for the system to flow more air than the engine will ever require. They can easily detune the engine through their engine management system (Air/Fuel ratio, ignition timing, valve timing,...). However they rarely make the intake the restriction to the power the engine can produce. Next, lets talk about an intake larger than the engine requires. If you want to put two intake tubing systems on the car. You will essentially be doubling the volume of air that the engine can pull from. At first this might sound like an ideal way to go. But, in reality the engine's low pressure signal, created when an intake valve opens as the piston is traveling down in the bore, will have to pull from a much larger available volume or air (think of all the air hanging around in those hoses and tubing). Well it takes quit a bit of a low pressure signal to get all that air moving. Let alone moving at a high rate of speed. So what will happen is that the velocity of the incoming air will drop. This will in turn reduce the amount of air entering the engine, reducing torque, and consequently horsepower. How about gains from colder air? Well, I've seen many OEM Air temperature compensation tables found in the engine management systems software. For the computer to command a richer Air/Fuel ratio or more aggressive ignition timing the reduction in temperature must be large (like 40-50 degrees F). Therefore rarely will this help you in making power. Don't get me wrong. There are gains in reducing the temperature of the incoming air and associated tubing / ducting (heat soak reasons). But that’s a topic in its own self.Air, fuel, and exhaust are all directly proportional to horsepower. Increase them and you'll increase horsepower, provided you don't overgas or burn too lean. Most people will modify the intake and not take into consideration the exhaust end. You will need a bigger exhaust now that you have a better intake but with this healthy dose of air coming through you need to have a bigger better fuel system for optimal air/fuel ratio to create a good combustion for the powerstroke. I know these things for a fact and from experience. If you’re interested in improving the LOOKS of you’re under hood engine area, buy the chromed out intakes. If you want to increase power, put your money into something else (supercharger, stroker kit, turbo, Nitrous, better exhaust manifold, cams, head). Or find out what part of the intake is the restriction and alleviate that. That's my piece on the subject, you can take all the info and do as you wish with it, dismiss it or use it, either way I'm glad to get out to you the knowlede I have attained over the years to try to help you in making an informed decision.

 

holy crap, that was long......good discussion

 

ehhh... i'd say horsepower more likely = Head Flow + Fuel + Compression. Spark really has nothing to do with it on a stock or even semi-modified motor. spark is spark... a bigger/hotter spark on a zippo lighter won't give you a bigger flame. a bigger/hotter spark on a primer won't give you a bigger bang. however, with higher compression and more fuel, a bigger/hotter spark is needed (sometimes multiple sparks) to burnt the extra fuel orced into the cylinder. so, i don't recommend an ignition modification (unless you have nitrous or high compression).

the reason cold air intakes work isn't because it RAMS more air the plenum. a bigger filter surface area rarely makes a difference. intakes work by taking air from outside the engine compartment, rather than the hot air under the hood. the colder the air, the more compressed the O2 molecules are; and the more O2 molecules there are, the more fuel must be injected (to maintain stoichiometric balance). this results in more power (because of slightly higher compression).

the faster and easier this air/fuel can enter the cylinder chamber, the less the motor has to work on acquiring it. it's like breathing through a McDonald's straw as opposed to a coffee straw. the same way with exhaust (to an extent). exhaust flow can get to be extremely technical (cfm, efficiency, temperatures, unburnt mixture, vaccuum, etc.). basically, for a stock motor, a muffler does the job, but it can be hazardous to the rest of the motor if there is a lack of restriction. that's where vaccuum comes into play. with the right amount of restriction, it causes the gasses to flow at a faster rate, and the faster something exits, the faster it pulls something (which creates vaccuum pressure). you want this pulling effect, because this will actually help pull exhaust gasses from the other actively-firing cylinders during their exhaust stroke. this is why it's good to do research first, before going *****-deep with purchases. i've been known to spend 4 months doing research on what works and doesn't work. just make sure you do your homework!