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Old 01-30-2005, 01:33 AM   #26
Mechkiller31st
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I say do it and then get it dyno'd before and after so we can see what it does to the EJ25 Hey 10HP for $50 who can complain about that.
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Old 01-30-2005, 05:00 AM   #27
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FWIW, a couple years back I dyno'd my car with a JC Sports intake. Very similar to the so-called Ebay intake - didn't fit quite right, filter vacuum/PCV hoses didn't match up right, etc. I saw zero gain - I actually went home from the dyno and put my stock intake back on, because I figured at least with that I'm getting cooler air from the fender.

I then installed an Injen and went back to the same dyno a while later (not sure how long, but this was not a same day, head-to-head comparo like Kevin's) and gained about 7.5hp.

In other words, your results may vary....

Pat Olsen
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Old 01-30-2005, 11:49 PM   #28
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well im satisfied with MY results. (huge understatement)

Summit Racing sells 3" mandrel bent tubing... give me a year. i wanna see how hard it would be to make these suckers.
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Old 01-31-2005, 12:39 AM   #29
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Quote:
Originally Posted by Kevin Thomas
Also, you probably are going to have to purchase a Maf adapter. I didn't use the one that was provided by the owner (Shaun). I used the maf adapter I have for my Minnam intake, which is a perfect fit. It looked like Shaun had to modify a maf adapter to make it fit.

3rd note is that some of you ARE NOT going to like the air filter. I was going to include pics but when I swap cars, I left my digital camera in the other car. I'm sending this intake back today and it's all boxed up so I can't give you detailed pics. What I can tell you is not the quality of the filter element but the top of the filter looks similar 'to a thin metal screen'. Sure it will filter out some stuff but it's not an 'air filter' type of material. It's almost like sticking a panty hose over your maf sensor. \
ok. apparently i didnt read this too thoroughly before. yes, there is a very thin metal screen at the end of thefilter. and no its not good. i have a VERY fine dust on the inside of my intake cuz of it. first thing i do when i get the intake back, other than install it, is to get another filter. i dunno the company, but its 25$. its the typical cone filter with a inner 'V' filter. ill post [ics when i actually get it. /v\ <- thats the jist of it

another thing. i didnt mod a MAF adaptor. i made one. at the time, we didnt know there was such thing as a MAF adaptor. we used a bend we cut off the intake, and made our own with that and some spare sheet metal. i say spare but we paid 10$ for it. thats another thing i plan to get with the new filter(the adaptor).

another thing, to back Kevin up. if you plan to go out and buy an ebay intake, i can assure you that, if you get one from the same company i got mine from (which you prob will) it wont fit out of the box. it wants to put the filter in place of the strut tower(i have 1 pic of the intake before surgery). cutting, silicon, hosing, clamps, etc are all involved. yes this intake appears to make more power, but with that power comes work and fabrication. i posted in the original ebay intake post about this.

a breakdown of my intake is here:

http://forums.nasioc.com/forums/show...8&page=1&pp=25

i would be happy to answer questions or take more pictures if anyone is interested.

-Shaun
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Old 01-31-2005, 03:29 AM   #30
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Quote:
Originally Posted by Kevin Thomas
Is there a reason why this reasoning wouldn't apply to the stock intake as well? I'm an idiot so I'm sorry if it's a simple explanation. Someone else said the exact same thing on another forum where I posted this up. I never heard anyone say this about the Cobb intake.
I suppose it would apply to a stock intake. Saying that was a little redundant, since any mod will make more hp if it's in conjunction with something else. Take underdrive pullies for instance. Don't they "make" more power when used with, let's say, a larger turbo? BUT, I think you would realize much larger gains with something a little less retrictive than a stock airbox. I am a master of stating the obvious, by the way.
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Old 02-01-2005, 07:25 AM   #31
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ok. installed the stock intake (and looking, realized that my CV boots are cracked) and took it for a run. bogging is gone. 0-60 feels much faster, but isnt very measurable.
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Old 02-01-2005, 07:25 AM   #32
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ok. reinstalled the ebay intake (and looking, realized that my CV boots are cracked) and took it for a run. bogging is gone. 0-60 feels much faster, but isnt very measurable.
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Old 02-01-2005, 09:39 AM   #33
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I did this test in 2001 and everyone thought I was full of crap, I'm glad to see that I'm right. I bought one of these intakes for the MAP based imprezas, made an MAF adaptor similar to a Kartboy out of plexi and 3" exhaust tubing, then relocated my filter in the fender. I had to add a few more breather tubes because the 97 had 4 vaccum lines, that was done with simple copper tubing and fast setting JB Weld.

Being innovative and thrifty pays off, I paid 80% less then what a Cobb costs and got more power from it.

These intakes work well for the 93-02 Imprezas, the 03-04 Impreza have an IAT sensor that for some reason causes the intake to make this awful high pitched whistling noise when an intake is installed. I tried the ebay, AEM and one of my own custom jobs and still had little success in making it stop whistling.
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Old 02-01-2005, 09:46 AM   #34
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Quote:
Originally Posted by Patrick Olsen
FWIW, a couple years back I dyno'd my car with a JC Sports intake. Very similar to the so-called Ebay intake - didn't fit quite right, filter vacuum/PCV hoses didn't match up right, etc. I saw zero gain - I actually went home from the dyno and put my stock intake back on, because I figured at least with that I'm getting cooler air from the fender.

I then installed an Injen and went back to the same dyno a while later (not sure how long, but this was not a same day, head-to-head comparo like Kevin's) and gained about 7.5hp.

In other words, your results may vary....

Pat Olsen
'97 Legacy 2.5GT sedan
I remember this at Adrenalin motorsports, I had a very similar set-up at this time, JCSports 3" piping and a short extension for the filter and got no results either, switching to a 2.5" diameter pipe made all the difference.
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Old 02-01-2005, 10:24 AM   #35
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Quote:
Originally Posted by BrysImpreza
I remember this at Adrenalin motorsports, I had a very similar set-up at this time, JCSports 3" piping and a short extension for the filter and got no results either, switching to a 2.5" diameter pipe made all the difference.
I've been thinking about for sometime. I'd like to do another test to test this out though. I'm thinking that a 2.75" diameter piping would yield the best results. There's so much to learn in this area. The maf sensor housing is 2.5" but the throttle body diameter is 2.75" (from my measurments). I always seem to notice that my air/fuel ratio takes a steep dive after 5000rpm or so the more you keep doing a dyno run on an aftermarket 3" intake. There's something to be said about this. Other people have reported the same thing.

I know that after 5000rpm, the intake velocity is at it's peak (of course) and that all of my 3" intakes are the loudest at this point. I'm wondering if the drop in air/fuel ratio (sometimes as low as 10.2:1) is attributed to the 3" intake piping's length, diameter and/or sounder resonance coming from the cylinders.

Again, all of the 3" intakes I've tested has the air/fuel ratio taking a dive above 5000rpm. Someday, I'm going to figure out what's the deal with this. Maybe someone else will or have though.

Perhaps I can get some plumbers plastic piping together to test this all out.
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Old 02-01-2005, 11:24 AM   #36
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Kevin - I want to test 2.75 inch pipe as well. I have tested several intakes on my now ex's 2003 RS. The stock intake is 2.5 inchs, i made one intake that was 2.5 inch and a few different 3 inch intakes. All three intakes were from the stock air box to the fender, the 3 inch intakes were attached to a modified stock air box. 3 inch loses lowend, some of the punchyness was gone, but pulls to red line so well. I think there would be no loss in low end torque with 2.75 inch, but with good gains in the mid and top end. However i like to use abs plastic because it won't soak up heat like metal, and i have never seen 2 3/4 abs.
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Old 02-01-2005, 01:16 PM   #37
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I still think 2.5" is the route to go. It seems that when one uses a pipe bigger then the throttle body, all it is doing is slowing down the airflow to the manifold. By staying consistant throughout the piping you can keep the same flow rate into the manifold.

Basically by decreasing the effort to pull in air it seems to make more power. The volume of air coming in from the 2.5" piping seems to be the most efficient.

Much like putting something like 3" or 2.5" exhaust tubing on our cars, it does nothing but create dissonance just outside the cat and the muffler, too much air trying to leave at once. I know backpressure is a factor, but there are optimal sizes to maintain and even increase low end tq. and gain HP.

The "perfect" set-up for the 2.2 and 2.5 seems to be consistant through-out the years of testing and observation:
2.5" Intake pulling in actual cold air, not heated from the engine bay
2.25" Catback exhaust.
Proper Air to Fuel Adjustments
= Optimal Performance.
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Old 02-01-2005, 01:55 PM   #38
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People are claiming more power with eBay intakes than brand name intakes such as Cobb and Injen.. I haven't actually seen an eBay intake vs a brand name intake dyno plot in this thread yet.
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Old 02-01-2005, 02:43 PM   #39
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No one is claiming more HP then anything, we're just saying we spent 80% less for the same effect. I can tell you from dyno testing years ago we gain nothing from the JC Sports intake, but I gained 11hp at the wheels with a modded ebay cheapo.

JC sports has since gone out of business.
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Old 02-01-2005, 08:06 PM   #40
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Just curious, Kevin, what type of gains did you see with your Minnam?
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Old 02-01-2005, 08:58 PM   #41
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Quote:
Originally Posted by Zen
People are claiming more power with eBay intakes than brand name intakes such as Cobb and Injen.. I haven't actually seen an eBay intake vs a brand name intake dyno plot in this thread yet.

I haven't posted the Minnam intake results because I wanted the thread to be stock vs Ebay. Also, Minnam intakes came with a Greddy foam air filter if anyone remembers the SCC (Sport Compact Article). The JC Sports intake had a K&N air filter. My Minnam intake has a K&N air filter on it. I never tested the JC Sports intake with a K&N air filteron the Impreza.

I can post up the Minnam intake with the K&N air filter alongside the Ebay intake if anyone wants to see it. The Ebay intake beat it on the top end. The Minnam intake was the first intake I did 4 dyno runs on before changing it out for the stock intake, then the Ebay intake. All were done on the say day even though I had previously tested the Minnam intake before.

Somehow, I still don't think this would be convincing enough for peeps. The Ebay intake was 'custom'. It's likely all of them will be custom because they may have to be modified.

Wife calls for dinner. I'll post up the Minnam intake results so you can decide.
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Old 03-02-2005, 02:05 PM   #42
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Quote:
Originally Posted by iimiketii
What do you guys think about a EBAY intake on a 01 RS? do it or not? i'm cheap...haha
I dont think you'll see the same results on the MAP-based cars. My '00 RS ran disgustingly rich with a Minnam intake. My gas mileage was down almost 30 miles per tank.
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Old 03-02-2005, 02:10 PM   #43
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I don't know if the 04 is that much different then the 00 aside from IAT sensor and fewer breathers, but y2k245678910door is right, MAP based EJ's run rich after adding an intake. I've noticed my car is running much richer after the addition of an intake. I have it conservatively tuned with an S-AFC II until I can get to a dyno to tune it.
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Old 03-09-2005, 01:52 AM   #44
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Well, I had this thing on my car for about 15k, then took it off and put the stock box on sans piping for almost another 15k to present.

I'm not totally sure of this things history, but I do know at one point it was McDade's then RS22b's, and now mine. Supposedly it was an SPT intake. It does seem to be decent quality. I have no install issues whatsoever. I do need to get a new rubber gasket to connect to the TB. I also bought silicone hoses for the vacuums.

I just had it powdercoated to match my GFB pulleys and am preparing to put it back on. My car ran rich with it on, and as far as I can tell with it off as well. Either way, my mileage sucks. I have currently a borla header and stromung axle back. I had at one point with both intakes a single high flow cat section. No difference in mileage. HP was "alot" better with the highflow though. Some of you might remember this as McDade's intake of death... It was originally red...


Last edited by DJ 9iron; 03-09-2005 at 02:16 AM.
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Old 03-09-2005, 11:26 AM   #45
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I dont get the point of the breather being where it is, but at least it looks cool.
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Old 03-09-2005, 11:56 AM   #46
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If it's like the one I bought, there is an extra hole in the tubing that has no use. The breather is there to cover it. I just plugged mine, but never thought about putting a breather on it. Pretty smart.
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Old 03-09-2005, 12:11 PM   #47
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Quote:
Originally Posted by RS_to_WRX_swap
I dont get the point of the breather being where it is, but at least it looks cool.
Yeah, I don't exactly see the point either... Thats the way I got it, so I'm just leaving it as is...
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Old 03-09-2005, 09:00 PM   #48
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But you might just be making turbulence if air is comming in there. I guess its not a CAI so it really dosen't matter that its sucking in hot air too.
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Old 03-09-2005, 09:02 PM   #49
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Quote:
Originally Posted by RS_to_WRX_swap
But you might just be making turbulence if air is comming in there. I guess its not a CAI so it really dosen't matter that its sucking in hot air too.
My hoodscoop is open. And if you say it doesn't get cold air from the scoop you're crazy! I can take a drive, stop, pop the hood, and when you touch the intake(where the breather is) that thing is downright cold! So... Yeah, sitting in traffic it will take in hot air, but is that when you are realizing benefits from an intake?
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Old 03-13-2005, 10:28 AM   #50
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Quote:
Originally Posted by DJ 9iron
Well, I had this thing on my car for about 15k, then took it off and put the stock box on sans piping for almost another 15k to present.
Nice looking intake. I was about to say I don't see a use for the breather as well since I was assuming you had a maf based Impreza. On a map based impreza, if your car has a restriction in the intake forward of the intake piping, the breather could make up for it by letting air get in through it. Seems it would help out by leaning out the air/fuel ratio a little bit if the car were to run rich anywhere in the powerband.
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