legacycentral bbs

i recently purchased a 93 legacy (fwd) and am thinking about modifying my filter. Any pointers or brands i should look at?

first question is why.

Intake mods do hardly anything but make you louder.

That said, I would get a drop in K&N and then use a door handle screwdriver to drill into your stock airbox and put two 1 inch pvc on/off valves on the dirty side of your airbox. This is better than taking off the snorkus because it does essentially the same thing but is un-doable in about 10 seconds.

The airbox is not restrictive, it is the same size as the one used in a 300zx.

If he has ABS the additional openings are not possible.

I like the K&N panel filter replacement.

are there any other filters that work?

i put the stock turbo air box back on and am going to go up from the bottom for the added air ports.

Is there really no HP advantage to installing a cold air intake?

there is a gain, but it messes up your airflow readings, because the flow becomes turbulent around the maf, and the gain on the topend is offset by a loss in the midrange.

If its really a true cold air intake then there are gains. Problem is what most people call "cold air intake" is actually a HOT AIR INTAKE!!

The factory setup is already a cold air intake, remove the snorkus and possibly enlarge the opening and I think you have a pretty good setup.

I'd say keep your stock snorkus and filter. It has been designed to reduced turbulance and as someone already said the MAF is calibrated for the stock intake. If you mess with the intake you might get better flow but your car probably won't run as well just because the ECU gets bad readings.

I totally agree with the direction that Ciper is suggesting. Reducing restrictions in the factory design can actually get you a fair bit more HP (up to 10). If you remove the snorkus, enlarge the entranceto the air box and add some piping that feeds back into the fender you have a good start.

Then drop in a K&N to the stock box. Keeping the stock box is really the key part to preventing turbulence from messing up your air flow readings. And be sure not to over oil the filter after cleaning as that can easily foul your MAF.

Lastly, if you are handy, you can smooth out the bend and get rid of the turbulence after the MAF that is caused by the baffling in the upper intake. But this would require some fabrication on your part, and it depends on how far you want to go for just a little bit more power. Most just stop with the snorkelectomy and K&N...

If you have a N/A legacy you can get an intake from Weapon R. And they lowered the price about $50.

http://www.dragonintakes.com/subaru.html
It's just a short ram though, but they do sell an adapter that attaches to their filter and turns it into a cold air intake.

http://www.dragonintakes.com/accessories.html They call it a Ram
Air kit. It's actually pretty cool.

Another way to go (also works on turbos) is to buy a kit from www.ProCarParts.com for a 2nd Gen. Legacy (bolts right up to our 1st Gens) which comes with a filter. Then if you wanted to get the cold air, just order the Dragon filter and Ram Air kit!!!

scottzg wrote:first question is why.

Intake mods do hardly anything but make you louder.

That said, I would get a drop in K&N and then use a door handle screwdriver to drill into your stock airbox and put two 1 inch pvc on/off valves on the dirty side of your airbox. This is better than taking off the snorkus because it does essentially the same thing but is un-doable in about 10 seconds.

The airbox is not restrictive, it is the same size as the one used in a 300zx.

for exactly that sort of information i won't be doing any of your mods!, intake mods increase throttle response if they are done correctly, if your airbox is the same as the aussie rs spec airbox its more restrictive than your grandma's naughty bits, piss it all off and get a plate made up on the end of two 3"pipes, connect your MAF sensor, and stick a pod air filter in your front guard, it will do wonders for driveavability. but make sure you have your inner splash guard in tact or you'll have a very damp air filter.


note the section of pipe between the 2 rubber hoses on the intake, thats where my MAF used to be.

rsstiboy, they definitely increase throttle response, I noticed that with just a cone filter.

But there is much more engineering in the stock airbox than some of these aftermarket intake systems. The airbox and snorkus even create a lot of backpressure in the intake system, which gives a supply of air to the engine at a moment's notice, which helps low-end torque. The airbox also has a velocity stack, which helps again. Remember, air velocity is just as important as air volume.

Also, if airboxes were so restrictive and such poor designs, then why do WRX STi's have them? Somehow they're making 280hp out of a EJ20, with an airbox and snorkus. Or 300hp from the EJ25 in the US, still with an airbox and snorkus.

boostjunkie's car IIRC still has the airbox with a K&N panel filter, and we believe that car to be in the 250-whp range.

Josh and I switched back to the airbox because of MAF/idle problems. He has removed his snorkus for sound, and done a mod to the airbox for additional flow. I merely wanted to bring back my car's reliability and enjoy it as a nice daily driver.

So yes air intakes can be good when done right, but don't knock the airbox! Engineers didn't go to all that school for nothing!

rsstiboy wrote:for exactly that sort of information i won't be doing any of your mods!, intake mods increase throttle response if they are done correctly, if your airbox is the same as the aussie rs spec airbox its more restrictive than your grandma's naughty bits, piss it all off and get a plate made up on the end of two 3"pipes, connect your MAF sensor, and stick a pod air filter in your front guard, it will do wonders for driveavability.

Um, you do realize the question pertains to a n/a legacy. The differences between intake modification results are COMPLETELY different compared to a turbo car!! Whereas a turbo engine can rely on the positive pressure produced by a turbo a normally aspirated engine must rely more on flow rate of the intake (low and high, depending on the rpm) and turbulence into the engine.

FWIW sktngisnotacrime, I had the Injen Race Division cold air intake on my car when it was n/a. I didn't have any problem with driveability or the maf etc.. It sounded great and performed well.

MK

One more post:

http://www.cobbtuning.com/tech/airflow/index.html

EJ22TGC8 wrote:I'd say keep your stock snorkus and filter. It has been designed to reduced turbulance and as someone already said the MAF is calibrated for the stock intake. If you mess with the intake you might get better flow but your car probably won't run as well just because the ECU gets bad readings.

The snorkus does nothing.

It is a silencer. Incoming air swirls around in the chamber and goes up the intake pipe, effectively slowing intake charge, and reducing noise. It also decreases throttle response.

Pull the snorkus, enlarge the hole on the airbox, and run a K&N panel. That's about as good a setup as you can get.

subyluvr2212 wrote:boostjunkie's car IIRC still has the airbox with a K&N panel filter, and we believe that car to be in the 250-whp range.

Hehe. It's not my car anymore . . .

Although, I don't mind you guys still calling it my car

I usually refer to it as "the boostjunkie Legacy."

LOL!

subyluvr2212 wrote:boostjunkie's car IIRC still has the airbox with a K&N panel filter, and we believe that car to be in the 250-whp range.

So yes air intakes can be good when done right, but don't knock the airbox! Engineers didn't go to all that school for nothing!

engineers also design things to be more quiet and to de tune things so don't think everything they do has a positive outcome!

there is no 'beleive the car to have x amount of power!' put the car on a dyno and prove it! my car is proven to have 242whp out of a internally std 2ltr motor on 17psi.