Jump to content
LegacyGT.com

Cool air intake


chefx312

Recommended Posts

I've been wanting to get a cool air intake for awhile but have always heard mixed reviews. Does it add much HP? And does it help gas mileage or take away from it? I had a guy at the Subaru dealership tell me that it makes gas mileage worse. Give me any info you can.
Link to comment
Share on other sites

I don't know too much about it so let the rest of the members on this forum correct me if I'm wrong but from what I understand...

 

CAI's or cold air intakes tend to improve power at higher RPM's by anywhere from 0-15+hp, but usually somewhere in the low teen range. However this is offset by a slight reduction in torque at low RPM's.

 

So taking into account the fact that you are adding a CAI for power gains, I assume half the time you are going to be revving high, which then will reduce your gas efficiency. If you are driving around under 2k RPM's all the time... idk, it seems like you might get the same or better gas efficiency.

 

Typical rule of thumb... if it increases power, it will decrease gas efficiency. This is logic.

Link to comment
Share on other sites

I don't think that's true...

 

If you get an intake, it allows a faster flow of air into the engine. However to match that and to simultaneously prevent from running lean, you have to also input more fuel, thus using more gas, at higher RPMs. You accelerate faster but use more gas.

Link to comment
Share on other sites

depends which kind of intake. short ram intakes are designed for high end power, longer cold air intakes are better for low end. it has to do with the resonance of the pipes.

 

if you get an intake, get a tune for it.

Link to comment
Share on other sites

btw you're not getting much HP out of an intake on the stock turbo. it is hard for it to flow enough air to max out the stock box.

 

panel filters are a decent option....read around, though. nothing is perfect without a tune, including panel filters

Link to comment
Share on other sites

  • 3 weeks later...

Hey quick question:

 

I'm still relatively new to the "modding" world, but I'm ready to learn! I drive an '09 NA Legacy and I took off the bottom half (silencer/resonator w/e you call it) of my stock air intake. It sounds like it is sucking in more air from underneath, giving more air to the engine and giving it a louder sound already. Is this bad? I know it means the air/fuel mix will be running leaner, but is that bad? I like the sound and it feels like there is more power in the upper RPMs (3000+). Will I see any changes in HP or gas mileage?

 

Anyone have any advice? Please advise. Thanks

Link to comment
Share on other sites

On the original question...CAI...

 

I installed an AEM CAI. It did increase my MAF a small amount and decreased my inlet temps slightly (also a good thing). The AEM draws from way down in the front well, way away from the engine bay; I also insulated the intake pipe (yes, the stocker also draws from "outside" the engine bay (front of car)). Only drawback is the intake can be more susceptible to water ingestion in an extreme case (I haven't had any issue yet).

 

I'm a little past Stage II, so I don't know if a stock car would see the same or not, as pointed out by another post.

 

You do need to be able to tune for it (change the MAF scale).

Link to comment
Share on other sites

Hey quick question:

 

I'm still relatively new to the "modding" world, but I'm ready to learn! I drive an '09 NA Legacy and I took off the bottom half (silencer/resonator w/e you call it) of my stock air intake. It sounds like it is sucking in more air from underneath, giving more air to the engine and giving it a louder sound already. Is this bad? I know it means the air/fuel mix will be running leaner, but is that bad? I like the sound and it feels like there is more power in the upper RPMs (3000+). Will I see any changes in HP or gas mileage?

 

Anyone have any advice? Please advise. Thanks

 

I think that is correct. CAI will definitely bring in more cold air (hopefully). Cold air is more dense than hot air. Cold air (dense air) will also make combustion better since there is more oxygen present. This will in turn lean your fuel out in the combustion chamber. So you may have to richen the fuel a tad to avoid backfiring...or was it misfiring. I do not remember.

 

All in all, when you get a CAI make sure you tune the car properly. And no, it will save you gas as the same amount will still be pissed into the chamber. The only difference with a CAI is the fuel will burn more efficiently and slightly earlier.

 

I can be wrong here.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.



×
×
  • Create New...

Important Information

Terms of Use