Air Filter Questions

[Bimmerman]

Hi all,

I'm planning on desnorking and installing my ebay intake tomorrow after work, and had a couple of quick questions about air filter options. I have seen many pictures of ebay intakes on the stock air box and many of a cone filter instead attached to the intake/MAF. I plan on eventually welding an aluminum cold air box for the car but in the interim would it be better to use the stock box or slap a cone filter on the end of the MAF/intake? When using the stock box, is the Green or K&N filter better than using the stock one? Finally, is there enough of an improvement over the stock box with a CAI box to justify the trouble/expense?

I have a 95 Legacy L Wagon w/ABS for reference

Thanks a lot for the help!

[auspex]

I just switched to the intake->stock airbox route and it feels better to me. Felt like my motor couldn't suck enough air to really take advantage of the cone, so I was bogging down too much on the low RPM's.

Now throttle response is much better.

-mike

(link to what it looks like in my sig)

[ooberdoob]

a cone will destroy your low RPM torque.

i didn't believe it, then i broke my airbox and had to use a cone, and though it sounded insane, there was no tq down low. so strange.

i run the ebay intake to the stock airbox, with a 90* PVC elbow into the fender, white part of the box removed and of course de-snorkused.

fine by me. i can't wait to get my SPT muffler on.

[AJM]

I simply don't get those of you on this board who have problems with cone filters. It really baffles me.

I've run a cone and or mushroom filter for over a year now and I have awesome low end torque even when that was aboutt he only mod I had.(96 ej22). I have no bogging at under 1000 rpm or even lower. (meaning second/ first gear/ sometimes third, if someone is driving thier car at sub 1000 in 4th or 5th...they need help.)

If you feel you must keep "teh torque boxores" remove the fender siclencer, it's huge and massively restrictive.

You also might want to consider doing this to the air box ,and yes a K&N is better than stock.

http://i168.photobucket.com/albums/u198/ajm32386/tehtorquebox.jpg

[Sarra]

I had a cone filter until the metal bracket I had holding the filter steady broke. Right now, I've got the stock airbox on, but no snorkus. It was working fine until my crappy OEM filter got dirtificated, now my car has some problems... Plus, it's getting time to change the oil, and almost time for the big 120K.

[ooberdoob]

i've got an EJ25 DOHC. different creature all together, it's also made to rev high, just how it is.

i didn't like the cone setup. i know i lost tq. i had to rev the hell out of it to go.

sounded crazy though.

i've got 127k now. i can't believe i've already had the car for 64,000mi. 2 years last march.

[Bimmerman]

@AJM- The picture just shows holes drilled in the air box, right? Nothing more to it than that?

It seems that those of you who have had problems with a cone filter have an EJ25 and AJM has the EJ22... is the difference in the motors significant enough to cause a major torque loss on the EJ25 but not the smaller 22?

Thanks for your replies, guys. Much appreciated.

[Sarra]

i've got an EJ25 DOHC. different creature all together, it's also made to rev high, just how it is.

i didn't like the cone setup. i know i lost tq. i had to rev the hell out of it to go.

sounded crazy though.

i've got 127k now. i can't believe i've already had the car for 64,000mi. 2 years last march.

It is made to rev high, but it has better lower end torque than the SOHC engines do. SOHC = pulls hard in the mid range, not quite so in the upper and lower. DOHC = pulls more consistantly, but not quite as much.

[Wiscon_Mark]

I didn't see much loss with the cone filter on the EJ22, however, the clutch was problematic at the time, and I couldn't really do much of a test. AJM may have just had a better quality filter than the others.

[AJM]

@AJM- The picture just shows holes drilled in the air box, right? Nothing more to it than that?

Indeed, gives the air box a bit better flow ,and costs you almost nothing. Just make sure any holds are below the filter. :wink:



You all could be right, it could be my setup, or it could be a difference between ej22 and ej25. I don't have a ton of experiance with 25's ,so perhaps it is a very real problem with you guys. Sorry if my last post was a bit hasty.

[ooberdoob]

ah, swissing the airbox.

most common mod on my old ZR2 boards. provided a hell of a sound.

that 4.3L didn't need any more excuse to swallow gas but i sure put my foot in it.

swissed airbox + flowmaster = orgasmic. to me anyhow,

[Sarra]

It's also a common mod on the Toyota trucks. At least the pre VVTi Toyotas.

[AJM]

It works, Trust me :grin: Very very cheap...

[Jedi Taxi]

lol, high rpm power. I once had this 1986 toyota corolla GT-S. Yeah yeah, i wish i didn't sell it blah blah blah. Anyways. Common swap in that car was to go with the 1.6L 20valve 4age from japan. with the proper modifications, it could run up to a 13.5:1 compression ratio, and up to 12k rpms. it also didn't sound as rice as it did indy car. Only problem with it, without NO2, turbo or supercharger, people have a hard time getting it past 280hp. though their was never the mention of it not being a reliable engine. That 4age engine was a hell of an engine with a well though out oil passage set up when it was developed. Never had any of the shit im having to put up with in my DSM. Still, i can't decide wether or not i should make a dry sump set up for this 420a while i have all of it apart and all that way the engine wont flip out on me when i take corners. mabye grab a more aggressive intake cam off a 2.0L neon R/T to get an extra 10hp. make the water pump run off an eletric motor instead of the timing belt, mabye gain some more power thats normally lost.

[AJM]

lol, high rpm power. I once had this 1986 toyota corolla GT-S. Yeah yeah, i wish i didn't sell it blah blah blah. Anyways. Common swap in that car was to go with the 1.6L 20valve 4age from japan. with the proper modifications, it could run up to a 13.5:1 compression ratio, and up to 12k rpms. it also didn't sound as rice as it did indy car. Only problem with it, without NO2, turbo or supercharger, people have a hard time getting it past 280hp. though their was never the mention of it not being a reliable engine. That 4age engine was a hell of an engine with a well though out oil passage set up when it was developed. Never had any of the shit im having to put up with in my DSM. Still, i can't decide wether or not i should make a dry sump set up for this 420a while i have all of it apart and all that way the engine wont flip out on me when i take corners. mabye grab a more aggressive intake cam off a 2.0L neon R/T to get an extra 10hp. make the water pump run off an eletric motor instead of the timing belt, mabye gain some more power thats normally lost.

Are you awlays going to ramble on about non subaru stuff around here.

[Reason]

lol, high rpm power. I once had this 1986 toyota corolla GT-S. Yeah yeah, i wish i didn't sell it blah blah blah. Anyways. Common swap in that car was to go with the 1.6L 20valve 4age from japan. with the proper modifications, it could run up to a 13.5:1 compression ratio, and up to 12k rpms. it also didn't sound as rice as it did indy car. Only problem with it, without NO2, turbo or supercharger, people have a hard time getting it past 280hp. though their was never the mention of it not being a reliable engine. That 4age engine was a hell of an engine with a well though out oil passage set up when it was developed. Never had any of the shit im having to put up with in my DSM. Still, i can't decide wether or not i should make a dry sump set up for this 420a while i have all of it apart and all that way the engine wont flip out on me when i take corners. mabye grab a more aggressive intake cam off a 2.0L neon R/T to get an extra 10hp. make the water pump run off an eletric motor instead of the timing belt, mabye gain some more power thats normally lost.

Are you awlays going to ramble on about non subaru stuff around here.

lol owned

[02LGT]

What do the drilled holes under the air box do? Wouldn't it be bad since it will be sucking engine bay air? Correct me if I'm wrong I'm new to this setup.



I simply don't get those of you on this board who have problems with cone filters. It really baffles me.

I've run a cone and or mushroom filter for over a year now and I have awesome low end torque even when that was aboutt he only mod I had.(96 ej22). I have no bogging at under 1000 rpm or even lower. (meaning second/ first gear/ sometimes third, if someone is driving thier car at sub 1000 in 4th or 5th...they need help.)

If you feel you must keep "teh torque boxores" remove the fender siclencer, it's huge and massively restrictive.

You also might want to consider doing this to the air box ,and yes a K&N is better than stock.

https://sl-i.net/FORUM/

[Jedi Taxi]

:-( :tear:

yeah.....im bad at that.....

oh and there is filteration on that side of the box, in fact, its right before the filter. Basically all its doing is making the stock box flow with more air!

[Wiscon_Mark]

What do the drilled holes under the air box do? Wouldn't it be bad since there will be no filtration on that side of the box?

No filtration? He drilled them on the pre-filter side.

They just give you a little more air when needed.

[dodik]

i had cone filter on my old BD 2.5l and no torque problems but then there was no torque to begin with.

[Reason]

i had cone filter on my old BD 2.5l and no torque problems but then there was no torque to begin with.

You hit that right on the head.

[Jedi Taxi]

(insert more rambling here)

...in the long run, what i was getting at was that the stock air intake was restrictive. when the holes where drilled,you could ACTUALLY here the car! (this was the first mod on AJMs car) before this, it was vaccum silent! WHAT A BORE!

[AJM]

(insert more rambling here)

...in the long run, what i was getting at was that the stock air intake was restrictive. when the holes where drilled,you could ACTUALLY here the car! (this was the first mod on AJMs car) before this, it was vaccum silent! WHAT A BORE!

Haha thats better. :grin:

[rougeben83]

Well, I've been running a CAI made from bits of AEM, Ractive, and my own creativity and all I noticed was more noise. :lol:

[02LGT]

I've seen this done to one of my friend's 01RS which he got rid of for a jeep cherokeeeee...?!? I did hear more noise but did not drive his car so dont really know how the performance gain was...

So what you guys are saying is that if i drill holes into my airbox where the picture shows, there will be some kind of gain in performance and noise? no harm done to the sensors no CEL? I know it's right before the filter, but would it kill the life of the filter in half or more since there are tons of small dirt particles inside my engine bay. Also, seems like It would be the same kinda deal with the shortram theory, wouldn't hot air from engine bay area get sucked into from the holes which would be located right underneath the block and manifold? please correct me if what I'm saying is wrong, this is just my opinion and observation. I learn alot of new things through this forum. I am not disagreeing with the setup i just need some solid evidence so i can go ahead and do this to my car :grin:

[rougeben83]

In all honesty, that swiss-cheesed airbox is an old bracket-racer trick and it did work on a lot of old cars for a short while...

But it won't make a lick of difference performance-wise, aside from the placebo affect and extra noise.

Will it adversely affect your car? Highly unlikely.

Will it make you snap your head back when you step on the gas pedal? Only if you snap your head back yourself while you're stepping :D

[02LGT]

lol...ok...i guess this would be a useless mod...until someone proves YOU wrong...or my opinion.

btw, how many holes do you need to drill? and how big are the diameter of the holes?

[Jedi Taxi]

i would go with using a 1/2" drill bit with however many holes you want. Just so long as it doesn't go within 1" of the airboxes base where it mates with the body/frame rail.

[Khanhfucious]

It's also a common mod on the Toyota trucks. At least the pre VVTi Toyotas.
Except that instead of a bunch of tiny holes, we put a single ginourmous one!

In the case of my 00 4Runner, I cut a 6.5" hole. :shock:

[Plays_with_Toys]

It's also a common mod on the Toyota trucks. At least the pre VVTi Toyotas.
Except that instead of a bunch of tiny holes, we put a single ginourmous one!

In the case of my 00 4Runner, I cut a 6.5" hole. :shock:

A classic mod. The marine bypass something or other mod. Put a big hole in, and then put one of those removable water valves in there for when you go four wheeling.


Instead of swiss cheesing, desnork, then run a pipe into the fender and close off the holes that lead into the fender. Or run a CAI. With the swiss cheese you are getting more air in, but it's warm engine bay air... Why not just cut the whole bottom of the filter box off, so all you have is just the part that holds the panel filter. Massive quantities of air. Stuff it in the fender and you're even better off.


EDIT: It's the Deckplate mod. Here's a link: http://www.yotatech.com/f130/deckplate-mod-75169/

However, our airbox wouldn't benefit from this that greatly because it sits inside the engine bay, behind the radiator and there's a nice cold fender right there.