merckx racer

When I bought my NFR '02 S the airbox cover was missing.

I did some repair on car to get it running unbeleivably powerful now..
new plugs..new IAC..induction system carbon blowout..
so I love the car as is I want it to be
maximized and I have no interest in FI but will probably
gear(4.77 will be awesome for AP1 with 18" wheels).

So my question...Ive seen some guys state that I'm losing
power with airbox cover off especially in VTEC but I don't
get this as it seems to me airflow is now much greater
for intake(similar to aftermarket intakes).
I understand "heat soak" from running engine but if
car is in motion air draw is front of engine heat
and moving car will keep it there.
thanks for any input!

zeroptzero

Have a look at what is located in front of the air box and behind the bumper, that's where your air flow is coming from and that object runs about 200 degrees F. most of the time. You lose approx. 1% in power for every 10 F degree increase in intake air temp.

cdelena

I would think most of the air draw is under hood behind the radiator and therefore warm and not desirable. Your guess on power impact.

Gears and 18" wheels can be a big change so I suggest you find locals that have gone that route and get a first hand look before jumping.

jimi

use the stock air box. The car is balanced from the factory by F1 engineers, unless you're drag racing 18" wheels/4.77 gears will only impede you & you sure won't be driving a AP1. Whatever you decide good luck.

sillyboybmxer

truth.
put lid on

InVTEC

you tube a dino for lid vs no lid. I saw it somewhere on there and the dino proved that no lid = loss in power.

Utah S2K

Yes you are losing power with the cover off. The intake air is hotter coming from under the hood. The air is less dense. Cold dense air is good. The reason many run cold air intakes..........

Utah

merckx racer

Firstly....thanks for responses...it seems to be
quite unaminous for the air box lid to be put ON!

I'm glad the $112. I gave to Rick Hendrick Honda(like he needs the $$..not!)
wasn't in vain...I like the bit quieter car anyway.

As far as gears and 18" wheels..I purchased the car with the 18" Axis wheels
and love the look and handling very much.
I was concerned going from an '06 to an '02 about losing VSA but after owning
car for 6 months and even in wet weather 've never come close to even a hint
of losing rear traction.
Of course this is city driving so obviously I'm not pushing grip limits
on the street but in regards to gearing I did gear my '06(4.10 to 4.44) and
after looking at gear conversion charts the 4.77 for AP1 is much more practical
than 4.44 for AP2 in with longer gearing of AP1 will help me acheive higher
gear speeds across entire range.
With that said..I would presume 18" wheels would help reach higher(by a bit) speeds
in each gear also..so considering I don't race of any type and only drive interstate
maybe 15% of my driving gears should help my drive experience with really only
reaching 60mph tops most of the time.

SpitfireS

Btw.. I do not see the relation between 4.44 / 4.77 gears and 18" wheels.
As long as the revs-per-mile are equal to the OEM 16" or OEM 17" wheel&tire, 18" wheels with the right tires will not change anything.
Gears do.
Actually: high(er) profile tires on 18" wheels (less rev-per-mile) will do the opposite of higher diff gear ratio's.

Billman250

Done many roll on tests many years ago.

Do a third gear roll with 2 stock S2000s, one with lid on, other off.

The car with the lid on will pull away, quite a bit, every time.

Switch the lid to the other car, and it will pull away no problem.

Lid off=HP loss, fact. I estimate it is between 12-16hp loss based on the roll on test.