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All newer multiport engines have cold air intakes stock. I don't really see any reason to put an aftermarket intake on one of these cars unless you planning on really working it hard. Only thing it will accomplish is to make it breath a bit better maybe jump 1-2 HP more out of it. Nothing your going to notice.

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^ A cold air intake can create more HP in some cars providing the exhaust has a freer flowing mufflers to compliment it. It really boils down to how restrictive the factory box is though. 

 

 

You'd be better off making something yourself as it'll either be "free" or under $35. Want to buy one and you'll get fleeced with a 5hp increased (at redline) for $150+ which isn't worth it. You'd be better off pulling the back seats out and/or pulling the 35 pound spare tire out with the 5 pound jack. Factory mufflers are heavy too (roughly another 35 pounds) plus another 10 pounds for a resonator. Pull that 80 pounds out (spare tire, jack, factory muffler, resonator) while sticking a light weight muffler on with dual outs and you'll see a bigger performance jump than any cold air set up could ever offer. Back seats aren't heavy, but figure another 20 pounds and you'll be close to 100 pounds lighter. Versus another identical car w/o the weight cutting, you'll be faster unless you weigh over a 100 pounds more than the other driver. If you have heavy sub woofer boxes, they'll slow you down too along with increased braking effort and worse handling.

 

Light weight = faster.

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Waste of time and $$$ for a subaru. If you're wanting more power, reduce weight, fresh electrical tune up, seafoam. Ej22 is not a powerhouse. If you want a fast one, look at the guys who put an EZ30 in a 90s legacy.

 

Power gains from such modifications as cold air intakes will probably not even register for these cars. If it were that easy, Subaru would have done it.

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Power gains from such modifications as cold air intakes will probably not even register for these cars. If it were that easy, Subaru would have done it.

 Subaru wasn't performance oriented with these, so the last part of your statement doesn't hold water. Even on "performance" oriented cars, they still make the exhaust very quiet, shifting is smooth, use vibration dampening motor mounts, purposely add lag to turbos, cars sit high enough to accept tire chains, etc. etc. as they have to appease a larger audience vs. a select few, not to mention they have rather stringent Federal guidelines with cold start emissions and cold start drivability. Having a cold air-only intake actually presents some draw backs as it can affect AF ratios and affects warm up time. Another issue is NOISE. While most warm-blooded guys like the sound of a throttle wide open, a little old lady will say the sound scares her, a realtor trying to talk on a cell phone might not like the distraction either. A perfect example of a car that actually favors the select few would be something like a Viper, where it's a pure performance machine that forgoes niceties like a quiet cabin, spongy handling, and dead silent exhaust in favor of just being an all-out A to B machine.

 

 

@ahhsit These engines have mass air flow, so they should respond to a freer flowing exhaust and a cold air set up. The factory intake piping, especially if it's still plumbed into the fender, is restrictive. All those goofy contours are designed with keeping a throaty intake silent. If you want to see if any gains can be had, modify the air filter box (get one at a junk yard and hack that one up instead) and cut out the bottom of the box while leaving any structural supports alone. Basically you'll want the filter to have the straightest shot at pulling incoming air in w/o having to go through odd shaped piping. Install a new air filter that doesn't have the metal screen impregnated into it as that's actually a restriction. Try and not leave any sharp edges on the cuts to plastic box as that can create unwanted whistling. 

 

Get car warm and time some 0-60 runs (on ramps to highway are nice legal areas to do this just not in rush hour traffic) making an effort to run premium fuel and not change anything else or add/remove weight. If you only run 87, start running 93 and give the engine time to readjust to it. Since gas is dead weight, only add 1/3 to 1/2 a tank. Make 3-5 runs doing a 0-60 and write each time down (I think there are phone apps that make  this easier) then average it out. Install a modified box with a large opening so the filter gets a straight shot of incoming air, and repeat the 3-5 0-60 runs. Be sure to shift correctly and stay off the limiter as that'll slow you down. Compare the averages. I suspect that you might end up with a 1/10th improvement. 

 

Next, install a lighter muffler. I'm a fan of Summit Racing's Turbo Muffler, as they give a rather subdued sound note and weigh under 5 pounds. Their welded steel versions are completely different and obnoxious. Thrush's Turbo Muffler is basically the same as the quieter Summit muffler. Try and get a larger outlet i.e. if inlet side is 1 7/8" then make outlet 2 1/4" or 2 1/2" if possible, or get dual 2" outlets. Install it and run a straight pipe to replace the resonator. Try 3-5 more runs and average that out. See any difference yet?

 

Now remove anything that's just adding dead weight like the spare and jack, sub boxes, tools, etc. You might not think 40 pounds of dead weight in the rear adds up to much, but if you are familiar with how the car runs/pulls, handles, and brakes, you'll notice the car will feel a tad quicker vs. when you started. Your 0-60 times should be at least a couple tenths quicker.

 

Engines with lower torque output are easily affected negatively by weight. And a 3100 pound car is a greater strain to move than a 3050 pound car. Granted you won't shave a second off your 1/4 mile with what's mentioned above, but it WILL teach you some important lessons on how to actually make a car quicker that can follow you with future cars as it can be applied to almost anything. Also, I suggest a fresh set of NGK plugs and wires, plus a fresh fuel filter and fresh synthetic oil. Doing all that should return better MPG + a tad quicker daily driver. 

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