Engine/Power - EJ20T (pre-2006 WRX and JDM) There is replacement for displacement, it is forced induction - OEM 2.0 liter turbo engines in the USDM WRX. 90-94 Legacy Turbo EJ22 turbo engines can also be discussed here.

The cold air intake debate

Thread Tools
 
Search this Thread
 
Old Feb 7, 2005 | 05:01 PM
  #166  
WRXnifect's Avatar
Registered User
 
Joined: Jul 2003
Posts: 66
From: Sacramento, CA
Car Info: 03 WRX Wagon
I think the biggest problem is that people take tuner mags as being the gospel, a CAI kit that works on a speed density controlled honda doesn't work as well, if at all on a mass air sensor equipped Subaru. And it's not just Subaru's either, you can have the same problems on any MAF equipped vehicle by changing the airflow, even the direction or "tumble" of the airflow upstream (before) the MAF sensor. The people that make Pro-M mass air sensors have a good FAQ article at their site that describes some of the weird problems you can induce by changing things upstream of the MAF. One of the big reasons that OE's use MAF and the aftermarket does not is because of emissions. People that buy aftermarket fuel injection could care less about emissions. Someone show me an aftermarket stand alone fuel injection setup that uses pre and post O2 sensors and runs OBD-II monitors....I don't think there are any...you don't need them to run your motor in Alpha-N.
Old Mar 7, 2005 | 11:58 PM
  #168  
Maniac's Avatar
Registered User
iTrader: (6)
 
Joined: Jan 2003
Posts: 363
From: Sunny LA West Side
Car Info: Silver 2002 WRX Sedan
Originally Posted by Omniscience
...In another words, it's easier to suck in air through a straw than it is a garden hose...
HuH!?!?

"The ring is BUPKIS! Use the SCHWARTZ!"
Old Mar 28, 2005 | 05:03 PM
  #169  
lipster's Avatar
Registered User
 
Joined: Aug 2004
Posts: 4
From: Southeast PA
Car Info: 2004 WRX Wagon
Originally Posted by Omniscience
Colder air charges do give more horsepower, lean out air/fuel ratio, and reduce the chances of detonation.

Fine line there - "Leaning out air/fuel ratio" and "reduces the chances of detonation" in the same sentence. Lean too much and you could get detonation.
Old Apr 9, 2005 | 11:41 AM
  #170  
Donkey's Avatar
Registered User
 
Joined: Sep 2004
Posts: 131
From: Virginia
Car Info: 02' WRX
Originally Posted by Omniscience
Here's the problem everyone fails to see, both CAI and short ram have their benefits and faults. You have to decide which you prefer; colder intake charge or quicker spool time.

Short ram intakes allow the turbo to spool quicker. The shorter tubing allows less vacuum to follow each intake pulse. Everyone thinks the intake suck in air steadily, when in reality its a series of pulses, as the way the exhaust works (each time a cylinder fires the waste gas is pushed out, like a pulse, which then drives the turbo to suck in another pulse of air). In another words, it's easier to suck in air through a straw than it is a garden hose.

Cold air intakes create larger vacuum and turbulance, thus slowing down the amount of air that is sucked in. At the same time, it lowers the intake temperature which creates a denser air charge. This denser air absorbs more heat from the turbo which cools it and also gives a colder charge into the motor. The intecooler can then lower the charge more as it passes. Only problem is where you find the threshold where this stops working. If you suck in 20 degree dry air, the intercooler wont help cooling the charge because its already colder than it can cool. Colder air charges do give more horsepower, lean out air/fuel ratio, and reduce the chances of detonation.

To dismiss a CAI as doing nothing is incorrect, but you must weigh the benefits. I decided to go with a short ram because I wanted a faster spool and larger volume of air. Decide what you want to do and which makes the most sense to get there.
Still if the C.A.I. inner diameter is not the same as the inner diameter of the factory airbox outlet then your MAF is no longer calibrated.Now if the MAF was like the sensor that GM or Ford uses that is built into its own orifice then you wouldn't have a problem because the sensor will keep its calibration.That is the main problem.Its not that in theroy they don't work,just for the WRX's you can't just slap it on and go.So far only APS claims to have an intake that uses the factory size inner diameter for the MAF housing i believe so that would be bolt on and drive.
Old Apr 11, 2005 | 09:16 AM
  #171  
mmboost's Avatar
VIP Member
iTrader: (2)
 
Joined: Nov 2002
Posts: 3,639
From: Longing for my ol' white '02 WRX :(
Car Info: 2016 Acura RDX ... meh. Um, nice subwoofer?
Originally Posted by Maniac
"The ring is BUPKIS! Use the SCHWARTZ!"
Hahahahaha, awesome quote. (I might steal it )

This thread is dumb.

jason
Old May 11, 2005 | 11:45 AM
  #172  
mayrider's Avatar
Registered User
 
Joined: Feb 2003
Posts: 11
From: midwest
Car Info: 02 Black wrx sedan
i have had a ijen cai on for about 5 months and i see some dif. in it to factory
it has a more linear power curve, spools up at 2700 rpm instead of 3300rpm and it sound cool too
Old May 12, 2005 | 07:16 AM
  #173  
Kean's Avatar
Registered User
 
Joined: Nov 2002
Posts: 261
From: So. Ca., CA USA
Car Info: 03 WRX / 08 Forester
Originally Posted by mayrider
i have had a ijen cai on for about 5 months and i see some dif. in it to factory
it has a more linear power curve, spools up at 2700 rpm instead of 3300rpm and it sound cool too
......and with that, I'm unsubscribing to this pointless thread. .....it's like a merry-go-round.
Old May 12, 2005 | 09:45 AM
  #174  
Maniac's Avatar
Registered User
iTrader: (6)
 
Joined: Jan 2003
Posts: 363
From: Sunny LA West Side
Car Info: Silver 2002 WRX Sedan
Thumbs down I second that...

This thread is pointles... Nobody reads it before replying... Its a circle-jerk... Waste of server space... I wish it dies!!!

UNSUBSCRIBE!!!
Old Jun 14, 2005 | 06:20 AM
  #175  
BlueREX04's Avatar
Registered User
 
Joined: Sep 2004
Posts: 103
From: Racine, WI
Car Info: 04 WRX WR Blue
So I am sitting here and tring to filter out all of the b.s. for this cai and short ram debate.... its like a tennis match, very good points, and that is about it...

Does anyone have any dyno results on their WRX that would help.. . I am not about to drop $100 - $350 for a tube that I can buy from JC whitney for $20 and fabricate a bracket for the maf sensor... which I did for my neighbors 240sx last month.

I bought a BomX shory and after 50 miles I was getting a cel, I believe it was a 0171..
Old Jun 20, 2005 | 07:40 PM
  #176  
Maniac's Avatar
Registered User
iTrader: (6)
 
Joined: Jan 2003
Posts: 363
From: Sunny LA West Side
Car Info: Silver 2002 WRX Sedan
Aghhh!!!

Enough aready!
Attached Thumbnails The cold air intake debate-suicide.bmp  
Old Jun 24, 2005 | 09:58 AM
  #177  
midnitewrx02's Avatar
Registered User
iTrader: (9)
 
Joined: Mar 2005
Posts: 5,064
From: Elk Grove
Car Info: 2006 CGM WRX
dont get an intake, just get an airhog... i ran a 14.160@96.011 in my 02 wrx, with the help if removing the silencer, and removing the stock cat back exhaust.. i ran that timein 90 degree weather too..so if that airhog didnt help me run a 14.1 then i dono what did
Old Jun 28, 2005 | 12:09 AM
  #178  
VRT MBasile's Avatar
VIP Member
iTrader: (17)
 
Joined: May 2005
Posts: 22,776
From: Sunnyvale, CA
Car Info: '13 BRZ Limited / '02 WRX
for the whole "cooler air entering the turbo=cooler air exiting the turbo" debate you have to look at how long the air is in the turbo. Is the air in the urbo long enough to reach the same temp as the turbo itself? the colder the entering air is, the longer it will take for it to heat up. Seeing as a CAI does not alter the time the air is in the turbo, cooler air entering=cooler air exiting
Old Jun 28, 2005 | 01:35 AM
  #179  
Kevin M's Avatar
Registered User
iTrader: (12)
 
Joined: Nov 2002
Posts: 18,369
From: Reno, NV
Car Info: 1993/2000/2001 GF4 mostly red
The issue is less about air temp and more about MAF calibration. With an intake that doesn't skew MAF readings, then cold air is better than warm air no matter how you slice it, unless your turbo is just so damn big that the CAI can't flow enough to fully support it. Then a short ram can be more beneficial, because the loss from the warmer air is more than offset by the reduced restriction.
Old Jul 2, 2005 | 08:59 AM
  #180  
projectwhiterex's Avatar
Registered User
iTrader: (1)
 
Joined: Jun 2005
Posts: 294
From: San Jose
Car Info: 2003 ASPEN WHITE WRX
after reading all of everyone's insight on Cold air and short ram...its given me and probably hella other people alotta info on what to get for our cars...thanks guys for the controversy between the two cuz that made it a whole lot easier for noobs like me to get whats best for our cars..thanks again



All times are GMT -7. The time now is 04:32 AM.