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cutting filter box


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why don't you just take out the "snorkel"....it's a long piece of plastic in a U shape between the engine bay and fender......take that out and you'll notice a big difference + it will openly draw air from the inside the fender instead of the engine bay

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thats what im sayin subaru styles.

 

theres a reason they pull fresh COOL air in from outside.

 

and if you cut it from the bottom , the inspection dorks can't see it!

 

hey I am licensed as one of those "inspector dorks" I dont use it for a living but you have to know you S*** to get that license. took me a couple of years. show a little respect. I know other states may have a bit more shade tree inspectors but not here.

 

as for the legality. on a FI car with no heat riser you can chop away leagaly. on a heat riser system like I assume Brian had. no you cannot.

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Originally posted by rallyruss

hey I am licensed as one of those "inspector dorks" I dont use it for a living but you have to know you S*** to get that license. took me a couple of years. show a little respect. I know other states may have a bit more shade tree inspectors but not here.

 

Good thing the guy posting isn't in CA:rolleyes:

 

Show a little respect? I know inspection dorks in 4 states.. I stand by my assesment. Don't get all bent out of shape if it doesn't apply to you.. Offense toward you or any of California's highly trained automobile inspection professioanls wasn't intended.. The assesment was based on real experience with real inspection dorks.

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I flowed the intake with and without bottom, and with and without an air filter on a superflow airflow bench, turns out that the difference between a stock setup and the removal of the bottom of the box nets about 1 cfm, which in optimal conditions nets about .33 hp, all this mod really does is add noise, sure its cool but it won't get you any faster. sorry didn't want to poop on your popsicle, a better intake from the top of the throttle body out, would definately add flow, that big kink in the intake at the TB is horrific.

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Noah, I have done this on two turbo cars and there is much more of a difference than that. I'm talking about 60MPH in 4th gear before, and 90+mph in 5th after, with the same car, on the same gnarly freeway climb (vantage hill in WA FYI).. I would chalk up the difference to turbo vs NA.

no offense meant toward your method or results, but this is literally the only change I made to that car, with stock exhaust BTW. having the pedal to the floor on a freeway hill is a lot different than a butt-dyno in city traffic too; i don't trust that method ;)

I would rather cut out the bottom of the filter box than yank the intake muffler, because yanking the muffler is more work IMO, and cutting out the bottom completely bypasses the muffler anyway.

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I did the cutting mod many moons ago. It definitely made the engine more "peppy". The biggest drawback is the airflow that you eventually lose due to a clogged filter. Seriously, the best thing to do is adapt your MAF to fit a nice cone filter. You can snake one off of a Nissan sentra. not sure which years exactly. mid '90s though.

 

The sound is undescribable. Sounds amazing i think. made my SPFI NA sound turbo'd. Nice whooshing sound. If you can't fford the cne setup, go for the cut-out. it's worth the 5 minutes it takes to do.

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isall good Cabez Im not bent. I just have to stand up for my kind. Im shure you would do the same. It takes a lot more than that to piss me off. we can still be friends:D

 

baccaruda Its not that hard to pull the silencer. and mabey yours was cloged or sumting like that.

 

my brother inlaw just choped his air box on his WRX:rolleyes:

 

yeah more noise woo hoo.

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on the na cars chopping the box just lets you hear some intake noise... not any power increase..

 

but on the turbo cars, theres a difference..

I noticed that when i did this to my RX, It made more power past 5k, it pulled WAY harder... definately do this mod turbo or non..

as for the "sucking in hot underhood air" yes, it does.. and the effect on horsepower is not noticeable.. im from south texas folks, you heard it from me first

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well i am thinking about cutting out the air box , on my 88 turbo a/t full time 4wd wagon , i have a k-n filter which will help stop dirt etc from getting in , i run acell coil, 8mm wires, gap plugs .47. free flow exhaust, , some guys are saying no more hp gain and other say yes ? :banana:

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My own experience was that my NA EA82 felt weak starting at about 4000 RPM; it felt choked off. When I opened up the bottom of the airbox, it could breath dramatically better above 4000. Very noticeable free revving to 6000+. This is the only mod I made to intake, and none to exhaust.

 

The weak link is certainly the small opening the stock airbox has to let air in, from the fender. Obviously cutting a big hole in the box (out of sight on the bottom) lets it breath freer.

 

I gotta go with my experience, not the numbers. Shoot, mathematicians have "proven" that a bumblebee is too heavy to fly with those little wings!

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i have some nice 2" or is it 2.5" copper pipe and elbows i am going to replace that obstructive aluminum 4wd turbo thingy with

 

may even get to it this week ...

 

i too have the airbox mod and it made a difference that i noticed

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i have cut the airbox on two EA82 turbo cars and it produced the same improvement.. with the first car, i removed the intake silencer first and then later cut the airbox out; with the second car i jumped straight to cutting the box and the end improvement was the same.

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Originally posted by MaroonDuneDoom

I did the cutting mod many moons ago. It definitely made the engine more "peppy". The biggest drawback is the airflow that you eventually lose due to a clogged filter. Seriously, the best thing to do is adapt your MAF to fit a nice cone filter. You can snake one off of a Nissan sentra. not sure which years exactly. mid '90s though.

 

The sound is undescribable. Sounds amazing i think. made my SPFI NA sound turbo'd. Nice whooshing sound. If you can't fford the cne setup, go for the cut-out. it's worth the 5 minutes it takes to do.

 

The MAF adaptor comes off a '91-'99 Nissan Sentra 1.6L (engine code GA16DE).

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