l have an 05 Subaru wrx wagon and l wanted to put an intake and l seen this intake on tirerack.com that said it adds 40hp and the cost was $250... can an intake really add this much horse power?

wow. l would say no. from 224hp to 264hp with just an intake. The most l would say you could really get from it is 10 and that is at the high end,

NO WAY will this add 40hp! It can add 5 to 15 maybe, and help some on your fuel economy and throttle response. Make sure you go with a reputable brand, and check the manufacturer is website for performance specs, or call their tech support.

Do not expect any real performance improvements from a cold air intake. They r just eye candy. They may possibly flow air a little better, but no gains r from cold air. Here’s why.

First, u need to think of ur engine as an air pump. If ur 2.0 liter engine had the perfect cylinder heads, perfect camshafts, largest possible valves, perfect intake manifold, at 6500 RPM, it can only flow about 230 CFM of air. You have a turbocharger, so it may flow a little more, but not really all that much. It is not as though u r feeding a big block V8 with a big Holley carburetor. So how much airflow do u really need?

If u examine the air filter housing u will see that it draws its air from an opening in the radiator core support, drawing air from in front of the engine compartment. This air is already relatively cool.

On a cold air intake, even if it has some kind of intercooler, it will NOT cool the air any cooler than the ambient outside air temperature. Also consider that the air passis so quickly between the air filter & the throttle body, it ha no chance to heat up any significant amount. With a V8 engine, u gain about 1 horsepower for every 10 degrees Fahrenheit drop in temperature. Therefore, even if u could drop the incoming air 50 degrees, u gain a measly 5 horsepower. These gains r proportionately less on smaller 4 or 6 cylinder engines. So they r hardly worth the expense.

Another thing to consider is that ur engine is equipped with an EGR (Exhaust Gas Recirculation) valve. This device dumps hot exhaust gas from the exhaust manifold, into the intake manifold. A cold air intake can not make a difference over this extremely hot gas. Your engine is tuned to operate with this so it is not a problem.

You can accomplish the same effect by fooling the IAT (intake air temperature) sensor located on the hose that goes from the air filter to the throttle body. Un-plug it & put a 100K resister to bypass it. Your computer will think it is ingesting cold air all the time. It will increase ur fuel delivery, & give u a little more spark advance when u accelerate. It wo not affect anything else, but it will wake it up a little. You can get the resister from Radio Shack for about $1.

The air filter used in the cold air intake is the only component that may give u any real improvement. But with fuel injected engine, avoid the ones that use the washable oiled gauze elements. If even the slightest amount of oil from the filter gets on ur Mass Airflow Sensor, it will foul the sensor. It will send erratic signals to the engine management computer. This will mess up ur fuel / air mixture to the point that u could have even less power than u had before u added this component. If u already have one of these types of oiled air filter elements, u should clean the Mass Airflow Sensor with the correct cleaner every few months. Use Mass Airflow Sensor cleaner, & not carburetor cleaner, or u will destroy the sensor. Instead of the cold air intake, l would just simply add a low restriction air filter element.

For a little bit more than a cold air system, u can purchase a dry nitrous oxide system. For about $350 - $500, u can install a dry nitrous oxide kit that will add 50 - 75 horsepower to ur Subaru. This will give u performance gains u will actually notice. For a little over $500, u could install a wet nitrous system that could give u 75 - 150 additional horsepower, but with this, u risk breaking parts.

Checkout the Summit Racing Website.

The bang for the buck
Cold Air Intake
Cost = $200 Average. Horsepower gained = 10 HP, & l am being generous. About $20 per horsepower gained

Nitrous Oxide
Cost = $500 Average. Horsepower gained = 100 HP Average. About $5 per horsepower gained

ALWAYS be skeptical of ANY advertised claim. Obviously, they want to sell their product and one way to do that is make outrageous claims about how well it works.

While l am not familiar with a CA l ( Cold Air Intake ) for a WRX specifically, l can say that CA l is do help generally speaking. Most of manufacturers ( especially the Ebay stores ) have a tendency to greatly exaggerate the power gains but they do help.

How do they help? First, they place the intake somewhere outside the engine bay ( usually down by the bumper ) or away from the engine in order to draw in cooler air. Secondly, they use a less restrictive air filter ( compared to the paper filters most manufacturers use ) that allows more air to be drawn ( which in turn allows more fuel to be used for a more explosive charge inside the cylinder ).

My personal experience is that it does not give enough of a horsepower boost to noticed by my butt-dyno but it does offer a nice induction growl that was not present before & it does help slightly with ur fuel economy as long as u r gentle on the gas ( it can do this as it is less of a restriction in ur intake so it allows the engine to breathe more easily ).

nope. l had an 04 sti. and it added maybe a few horsepower. nothing significant.

Simply put it will add some power by fooling the computer into thinking it is getting more air than it as so it adds fuel & therefor giving u a few more HP. Any intake on an 04 & up will cause u problems with air/fuel ratio's. You may even find that it will not run as smooth. Now paired with a down pipe & some kind of engine management & it will be tuned to run fine but the stock airbox is shown to make about the same HP up to about 350HP so l would not waste ur money till u have some more work done first. A cool trick is to pull out the intake silencer that is in the fender & u will notice a little more spool sound as well as the blow off sound too. You have to take off the passenger side tire & get to it through the fenderwell. Not too difficult. You can find lot is of info on NASIOC.com & a lot of How To is with pictures on scoobymods.com.

No. Just adding on a different intake manifold MAY increase the horses about 5-10 horses more. Yet nowhere near what is being advertised. The only TRUE way to totally add that much more horse power would be to rebuild the engine. This means high compression/non-interference pistons; either skeletonized I-beam style connecting rodes or H-style ones; balanced crankshaft & cam shafts; larger intake & exhaust manifolds; a higher output oil pump; high compression cylinder heads & a turbo charger. And all that is going to cost u about $2500-3500 to do yourself. Do not ask about what the shops will charge u for it. You do not want to know.

Agree with mad jack on everything but the MAF sensor being burned out by the oils from the filter. l knowwww this is a big big controversy but l see it like this. The oil is sticky correct? The filter element it self is poruse correct? The oil sticks to the filter. & then the particals in the incoming air stick to the oil. ON THE OTHER HAND unless u reoil the damn thing like a mad man(by not following the directions) then well yeah youll screw the MAF. Ive heard both stories from master techs but l think it wont if u properly oil the filter. l know The oil will bake onto the wire element for the MAF. the MAF will go through its heat cycle & cook it on the wire & foul it out. but thats with a hot wire. Sea foam/sponge. Best filtration.


When it comes to NOS.BABIES NEED THE BOTTLE.

yes it does