Invest in some before/after dyno runs.  If you live in CA, make sure
you get one that's CARB-certified; I know someone that put a cheap
CAI in his car and pulled over for his loud (Uncle Ben) muffler
and then cited for the non-CARB CAI.  Cost $200 and a trip to the
test-only station for the ticket.

What's the mystery?  A manufacturer tunes a car to provide
the best combination of reliability, economy, driveability,
performance and emissions compliance.  An aftermarket tuner
can maximize top-end power at the expense of torque, so on.
The same tuning that a performance enthusiast likes might not
be acceptable by an mainstream driver.

I suspect much closer to the latter.

Dana

A manufacturer aims the car at the "lowest common denominator" buyer, which
means keeping it simple.  Also, they want to keep warranty work at a
minimum, and, over thousands of cars, boosting performance will have an
effect on parts life that they don't want to deal with.

I've done cat-backs, CAI and other bolt on mods and found them not worth the
money (unless all you want is a different look or sound).  Increased HP
claims are measured at the peak, not the RPM range where most of us drive.
An 8 HP gain at 5500 RPM might only be 3-4 HP at 4000 RPM - hardly
noticable.

My $.02 is that a supercharger or turbo is the only way to make a noticable
improvement in HP.  Fooling with CAIs, exahust, cam timing and chips can be
fun, but ends up costing a lot with a minimal gain.

Send this AEM guy right over with the detailed evidence for his
claims.  :)

Actually, manufacturers *deliberately* preheat the intake air to
be able to optimize the engine for a single intake air temperature.
The preheating is done by adding selected amounts of warm air
from the exhaust area to the other intake air.

The following quote is from the 5th edition of Bosch "Automotive
Handbook" as published by SAE:

"In addition to filtering the air, passenger-car air filters preheat
the intake air and regulate its temperature, as well as dampening
the air intake noise.  Intake-air temperature regulation is
important for the operation of the vehicle and for the composition
of the exhaust gases. [...] The constant regulated air intake
temperature improves engine performance and fuel consumption, and
decreases the percentage of pollutants in the exhaust gases as a
result of better fuel management and distribution of the air-fuel
mixture."

Of course, this does not need to mean that a specific *single*
measure such as maximum hp might not improve a bit by piping
in cold air where the engine expects warmer, in specific
conditions, (eg, when the car is sitting with the hood up
in a dyno testing stand, thwarting the intake's temperature
management by letting the hotter exhaust air escape.)

I just want to see the AEM guy to establish how the measurements
were done, and how repeatable they were (if they *were* repeated.)

I will beat the mod for $200.  Just send $200 and the mod right
over and I will have my hammer ready.  ;)

Maybe, just maybe, they think they *are* doing it right??  Modern
cars are very highly optimized, so any aftermarket stuff is likely
to make things worse, even if they try to optimize other items
(eg power at the expense of pollution.)  This is especially likely
if the chip is not specific to the particular car model and model
year it is used on.  For example, chip mods on Miatas are well
accepted to be worthless.

I have an aftermarket ECU on my Miata, but only since I also
have an aftermarket supercharger on it.  So OEM optimization
is nonexistent.

Leon

Because most buyers don't find intake howl appealing.

I don't know about this specific unit, but many "cold" air intakes
take their air in near the exhaust manifold's heat, while eliminating
the plumbing the factory put in to take in the air from somewhere
farther away where the air is cooler.

Because manufacturers have to meet emissions standards, don't want to
require premium gas and have to warranty the car.

I dunno.  This Wednesday I went to Infineon Raceway for the
Wednesday night drags in my (currently) bone-stock 2002 SE.
My pal Jeff took his '96 Civic EX with coffee-can cat-back
and CAI.  Neither one of us is very experienced at drag racing
and our times consistently improved, but my times were
generally 1.5 seconds faster than his.

Dana