I was looking at the dyno with all the intakes against one another and I was wondering about something, when you look at aem intakes on their site they say that every 4 degrees farenheit drop gives a horsepower so could that factor in to the total power too cause I saw a dyno for the f5 fujita and it was like 5.5 at 77.4 degrees and 7 hp gain at 94 degrees farenheit on the fujita site of course. I notice when i drive on a 65 degree day my car has so much pull and growl than compared to a 98 degrees it just revs up so much faster on the cold days.

 

I'm confused by this thread...

Colder air produces more power... it's pretty simple. That's the point of a CAI, to pull cooler air from outside of the engine bay.

 

yea but then ur exhaust is louder when its hotter haha

 

i love CAI during the winter
pop out the little vent to let some nice fresh FREEZING air in there (on dry days) - Ive also seen MPG gain doing that lol crazyness

 

I know cold air is denser and therefore gives more explosion in the cylinder but i was wondering if the temperature difference is factored into the dyno results.

 

The hp change drops off a tad till 2500rpm then its about 3-6hp more - Honestly its all about the noise and the wooshing sound (which I do like so its all good) - I would tell anybody thats looking for an upgrade, do things in pairs. Get an intake and exhaust or intake/header/exhaust - then you can atleast be happy with a sound change and power change.

 

so the 4 degrees for 1 horsepower counts so on a 94 degree day the horsepower could be 5.5 to 7. on a 60 degree day would be 94-60=34%4 =8.5 horsepower more. 8.5 plus 5.5=14 horsepower.

 

Double-check that web site, that info is WAY off. The general rule is you will see a 1% (percent) gain in HP for every 10-11 degree F drop in intake temp. Can't just add numbers to the HP figure you have to calculate % of the HP first. Ambient air pressure is also a factor. Here's a good link to read on this:

http://www.neuspeed.com/faq/faq_view...d=15&ltype=%5C

You should also keep in mind that on a cold day a bone stock car will also see an increase in HP. The best way to validate an intake's gains is to dyno it back-to-back against a stock airbox under the same ambient air temp & pressure conditions.

 

The ONLY horsepower gains (greater than 1 or 2) shown on various cold air intakes' dynos are gained by running lean. Which has nothing to do with the intake at that point. That's it. Period.

 

^If you're saying don't trust mfr's dynos at face value I would agree. But there's no question that some aftermarket intakes make power, and without any fuel management, as shown by this non-mfr intake dyno comparison:

https://www.scionlife.com/forums/viewtopic.php?t=92108

 

This would explain the larger differences in power between the different cold air intakes. Our car should dyno at 147whp stock (5spd manual), or thereabouts, on that same dyno. There's no way those CAIs are adding 15+ whp. The entire fact that their tC has an aftermarket head makes the differences between each intake's power that much larger.

In other words, on a 100% stock tc, the differences between the stock intake and a CAI would be < 5whp

 

Actually the biggest gain was Injen at +8whp (157.7 vs. stock+AWheader at 149.41). The intakes still made measurable power, not much but probably a little more than you thought they would, and will no matter what i/h/e setup you run.

Look, no one is saying intakes are big power boosters, you have to go F/I for that ... most buy them for looks, sound, and a little extra HP ... the main benefit IMO is better throttle response ...

 

It might make +8whp on an Alphaworks header, but if you dyno it on a stock head, I can guarantee you that it will not make +8whp. I even have an AEM CAI and love the sound, but that's the only reason I bought it. As far as throttle response goes, unless you have something other than a CAI, I'm thinking that it might just be in your head. The best way to increase throttle response is to decrease rotational mass, i.e. a lightweight flywheel.

I'm sorry to be so argumentative about everything, just trying to clear up any misconceptions about CAIs.

 

No problem, think we're clearing up several misconceptions here, even the original topic

As for throttle response, I can tell you that before CAI I had the symptoms of the old "throttle lag/delay" threads from 2005 (where some folks were actually putting spacers under their gas pedals ), while at other times just hitting the gas normally threw me back in my seat ... after bolting on the Injen I stopped seeing these inconsistencies and throttle actually became predictable ... now YMMV, I can only say what worked for me ...

That's why I don't ridicule people for putting on e-bay intakes (although I hope they at least buy a good filter to put on it) ... based on my experience I can see that replacing the stock intake with anything has to help throttle, even if it makes only a few hp ... plus cool sound as you mentioned ...

 

I hacked up my intake a few years ago and I might want to buy another intake for my 05 tc - in the past few years ...have any of the intakes been proven to be better then the others? Im not going to be running cai .... im just going to go short ram (i almost had a problem w/ hydrolocking in my other car w/ the intake in the wheel) - any feedback would be good. I know that there have been a few intakes come out in the past few years - I also know that I wont get much hp ...just a few .... but having a few extra hp accross the band is better then not having it.

 

In spite of what advertisers and ricers may think....

All SRI's are generally the same.

All CAI's are generally the same.


As long as the tubes have mandrel bending, fit the airflow pathway, have a decent filter on the end, and won't shed aluminum flakes from poor quality control... you'll get the same thing just about every time.

Dynos can be manipulated, and vary WIDELY even on the same vehicle from run to run. They are not meant for comparing 2 vehicles from across the nation... they're meant to show a before/after change on a single vehicle.

Note, this before/after change on that other vehicle MAY or MAY NOT represent what YOU gain on YOUR car. This is a concept that somehow gets mentally blocked, leading people to think one product is superior to another for arbitrary reasons.