The cold air intake debate
02-07-2005, 05:01 PM
#166
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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.
03-07-2005, 05:07 PM
#167
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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.
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.
03-07-2005, 11:58 PM
#168
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Originally Posted by Omniscience
...In another words, it's easier to suck in air through a straw than it is a garden hose...
"The ring is BUPKIS! Use the SCHWARTZ!"
03-28-2005, 05:03 PM
#169
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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.
04-09-2005, 11:41 AM
#170
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Location: Virginia
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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.
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.
04-11-2005, 09:16 AM
#171
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Originally Posted by Maniac
"The ring is BUPKIS! Use the SCHWARTZ!"
)This thread is dumb.
jason
05-11-2005, 11:45 AM
#172
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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
it has a more linear power curve, spools up at 2700 rpm instead of 3300rpm and it sound cool too
05-12-2005, 07:16 AM
#173
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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
it has a more linear power curve, spools up at 2700 rpm instead of 3300rpm and it sound cool too
05-12-2005, 09:45 AM
#174
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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!!!
UNSUBSCRIBE!!!
06-14-2005, 06:20 AM
#175
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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..
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..
06-24-2005, 09:58 AM
#177
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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
06-28-2005, 12:09 AM
#178
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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
06-28-2005, 01:35 AM
#179
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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.
07-02-2005, 08:59 AM
#180
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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
