Just installed air intake on 1.5L!

[E3pO]

Installed it yesterday and have driven about 40 miles with it.. I can slightly tell an increase in power, but i could be totally lieing to myself ;).

Anyway, I had a few questions... A buddy of mine said that it could possibly REDUCE my gas mileage due to something called VE? I'm guessing it means Volumetric Efficiency.

Here is our conversation:
let me explain
your engine is n/a
(naturally aspirated)
meaning..if you think about..the maximum amount of air it can suck in during an intake stroke is enough air to fill the cylinder to atmospheric pressure
now with older intakes, you obviously have restrictions such as filters and small throttles and airboxes which gives you less than atmospheric pressure in the cylinder (less than 100% ve)
however, with the newer engines (ie, the high milage toyota engines)
the intakes are "tuned" (are a certain length) so that the resonance of the air in the plenum forces more than atmospheric into the cylinder
this is also helped with that cars specific cam
meaning the car isn't wasting energy on "sucking" air in
however, an aftermarket performance intake could mess up the resonance
which would actually reduce ve and ultimately your gas milage
plus its going to mess with your maf, even it says it wont
which can be tuned out.

TL;DR
Basically he said that my engine might have to try harder to suck in air with the new intake then the old tuned intake that came with the car which results in lower gas mileage.

Here is the turbo I purchased, and a picture of it inside my car! :) (Attached)
http://www.amazon.com/gp/product/B00...00_i00_details

[RedRide]

Your friend might be right. Personally I have a real problem with CAI on most moderen cars as moderen air boxes are very well designed to begin with.

IMO, all you get with most CAI installs is a bit of noise that some misinterpect as increased performance and a "WOW" factor when you open the hood.

Just installing a free flowing filter like a K&N in the stock air box often gives better all around performace than a CIA

[ilikerice]

I do not have an intake. Like RedRide stated before, its seems purely a WOW factor. I cannot say for any gains in mileage though. I had a AEM CAI installed and did a dyno before and after. Only gained 1.5 whp. BUT I do like the sound alot..

I was kinda dissapointed, one of my brackets broke and the filter started rattling on my fog lamp.. decided to store it, fix it one day.. but I am happy with my stock setup. I feel no loss in hp, nor do I see a loss in time in autocross

[marcus]

my only say to this is try driving for a while with the intake then switch back to stock youll actually notice a difference.. about mpg sri gave me better gas mileage vs stock assuming that you drive exactly the same way...

[1.5]

Originally Posted by marcus

my only say to this is try driving for a while with the intake then switch back to stock youll actually notice a difference.. about mpg sri gave me better gas mileage vs stock assuming that you drive exactly the same way...

That is the problem. Once that intake or any performance part for that matter is installed, it makes you want to drive more aggressively which is what really hurts your gas mileage.

[E3pO]

I will admit that throaty sound of air being sucked into the engine followed by the engine revving up does sound pretty amazing :)... And when you have it to the floor and can hear it breath... oh man..

Here is a video of me driving to school this morning.

http://www.youtube.com/watch?v=oylR8Ej1ZNY

[cali yaris]

IMO, all you get with most CAI installs is a bit of noise that some misinterpect as increased performance and a "WOW" factor when you open the hood.

Like RedRide stated before, its seems purely a WOW factor.

Then I got a gain of 15 whp from a pulley, header and axle-back exhaust. Went from 92 to 108 whp.

You're saying the intake contributed nothing to that change in numbers, as measured on the same dyno, with reasonably close ambient temp and humidity? c'mon guys.

This argument just won't die. A well designed intake that lowers intake temps and increases flow makes some power; maybe not a lot -- but some.

And mods add to each other's increases -- I believe ilikerice has agreed to this in other threads. (but maybe it's my wishful thinking)

/rant

[cali yaris]

Just installing a free flowing filter like a K&N in the stock air box often gives better all around performace than a CIA

So free-flowing + colder air is worse? Makes no sense. Remember, the AFE is NOT a CAI (it's not CIA by the way). It's a short ram with an airbox. Let's make sure we are talking about the same thing so it's clear for everyone.

Sorry guys, I will fight misinformation every time I see it.

[matthewai]

would there be any benefit to putting a k&n filter or any other new filter on the afe ? or just clean the one it came with ?

[ilikerice]

Originally Posted by cali yaris

Then I got a gain of 15 whp from a pulley, header and axle-back exhaust. Went from 92 to 108 whp.

You're saying the intake contributed nothing to that change in numbers, as measured on the same dyno, with reasonably close ambient temp and humidity? c'mon guys.

This argument just won't die. A well designed intake that lowers intake temps and increases flow makes some power; maybe not a lot -- but some.

And mods add to each other's increases -- I believe ilikerice has agreed to this in other threads. (but maybe it's my wishful thinking)

/rant

100% agree on this statement.. I have said that before. This mod is beneficial when put together with other bolt on power adders like headers.. I was just stating CAI alone I found is not enough. More air in means more air out.. time to upgrade that exhaust manifold.

I still kept the CAI in means to one day buy an exhaust header and mid pipe from you garm.. BUT.. I really want that turbo also.. lol.. I am torn

[tk-421]

I did feel a bit of an increase of performance after installing my Simota SRI. While I do believe what your friend told you is true, I don't think OEM cars are tuned for 100% VE because of factors like varying altitudes and weather among regions, which would make tuning each car before selling it pretty much impossible in my eyes.

Opening up the intake helped with performance in my case because I tend to drive on areas that are of very high altitude (up to 12,890 ft above sea level*), so any increase in oxygen should help in that area.

As far as mileage though, I'm pretty sure it's not helping mine very much. No regrets, though! I really like the sound and the extra oomph is useful when going up hills.

[cali yaris]

It's a good discussion guys, and worthy of hashing out (even multiple times, lol).

Factory cars like the Yaris are tuned for mileage first, and performance second. I could put a management unit on a 100% stock Yaris and pull 10-15 whp out of it.

@ matthewai: yes, more airflow is always helpful in general. I have a K&N on my wife's Prius and, while I haven't dyno'd it, I swear it feels a little peppier (anything does on that car, lol)

Like RedRide stated before, its seems purely a WOW factor.I had a AEM CAI installed and did a dyno before and after. Only gained 1.5 whp.

Those two statements kind of conflict with each other. Just saying.... anyways.....That's nearly 2%, assuming identical session conditions. Not bad for a single mod.

Can you post the dyno's? I bet you picked up torque and got a more useful performance curve, too. Those are more important than the "big number", IMO.

[RedRide]

Originally Posted by cali yaris

So free-flowing + colder air is worse? Makes no sense. Remember, the AFE is NOT a CAI (it's not CIA by the way). It's a short ram with an airbox. Let's make sure we are talking about the same thing so it's clear for everyone.

Sorry guys, I will fight misinformation every time I see it.

My position is that once a car is moving, any intake ,stock or otherwise, will be sucking in cooler air.
Does anyone seriously think that a simple plastic shield will prevent the transfer of hot engine air when the car is standing still?

As I previously said, do a dyno test with the stock paper air filter installed, then with the filter removed, then with a CAI/SRI installed and compare the three results. It's interesting that very few do
If some suspect a dyno test that shows that a CIA does not give any benefits due to a faulty test, do we not have to use the same scrutiny (and have the same doubt) for those test that show a slight increase with a CIA, etc?

I'm shure you will agree that anything that helps an engine breath better can help top end performance no mater what kind of intake it is.
Yes, the Yaris it tuned for milage. Howver, do you really believe that that one way they tuned it is to restrict intake air flow?

[Jack Yak]

i have recently installed intake system similar to the one you have

i have K&N intake without air box

that's the pic

http://img638.imageshack.us/img638/8683/03022012530.jpg

and i really notice that the gas millage has been reduced ! !

[ilikerice]

Like RedRide stated before, its seems purely a WOW factor.I had a AEM CAI installed and did a dyno before and after. Only gained 1.5 whp.

Ok, I understand the contradicting in that statement.. but when I said "WOW factor", I meant as far as opening your hood and seeing a shiny pipe under their and the noise it makes. Not neck breaking acceleration.

I got my dyno sheets somewhere.. I dont have a scanner so thats why I havent posted them up and my camera on my phone is broken. I will see what I can do either today or tomorrow.

[Altitude]

Garm - What's the deal with that Simota Box intake you sell? I'm interested but don't see much in the way of reviews/opinions on it (in your forums). Just trying to get a feel if it has any advantages over the other CAI/SRI's you offer.

[1.5]

Originally Posted by cali yaris

Then I got a gain of 15 whp from a pulley, header and axle-back exhaust. Went from 92 to 108 whp.

You're saying the intake contributed nothing to that change in numbers, as measured on the same dyno, with reasonably close ambient temp and humidity? c'mon guys.

This argument just won't die. A well designed intake that lowers intake temps and increases flow makes some power; maybe not a lot -- but some.

And mods add to each other's increases -- I believe ilikerice has agreed to this in other threads. (but maybe it's my wishful thinking)

/rant

Exactly! Even if it is slightly more free flowing + colder air it is going to increase performance over stock. Even if it is only a few hp, in our tiny engines a few hp goes a long way.

And although the afe is not a legit CAI it does still help with responsiveness and midrange power.

[RedRide]

Originally Posted by 1.5

Exactly! Even if it is slightly more free flowing + colder air it is going to increase performance over stock. Even if it is only a few hp, in our tiny engines a few hp goes a long way.

And although the afe is not a legit CAI it does still help with responsiveness and midrange power.

If that is true, there should be a spectacular difference in performace between suimmr and winter temps.

Yes, there is some slight difference between drivng in 90 degree temps vs sub freezing temps. However, the diffence in intake temps (stock vs CAI) is insignificant as far as this is concerned.
"A few HP gain" just because you lowered the intake temps a few degrees? I don't think so.

Like I said.... when a car is moving all intakes are fed cooler air!
When a car is not moving, which intake do you think would be fed the coolest air..... A short ram the has its intake next to/ on top of the engine or, a stock air box that his its intake right bebind the grill?