TSXstock

Hey guys, I need an answer on this as I've been lurking and only find subjective results.

Do lower temperatures of intake air help the engine produce better fuel efficiency? Make it run richer?

I only need to know whether the COLD AIR factor affects MPG negatively or positively, please don't tell me driving habits/right foot/need new car/etc etc.

Some parts I have in mind:

Throttle body coolant bypass
P2R Throttle Body Spacer
Comptech Icebox (or any airbox style intake)
P2R or Hondata Intake Manifold Gaskets

Thanks guys!

justnspace

iTrader: (1)

denser air = MORE POWER.

TSXstock

Yes, I read that over many times.

Denser air = more fuel injected

Also read denser cold air = cleaner and more efficient combustion, and the volume of air remains the same, therefore same fuel is being injected

its just so confusing when you read about the claims posters make on these boards, gaining 1-2 MPG after installation and getting over the new mod and returning to normal driving habits

deadlyklappy12887

more power at the cost of reduced mpgs, prolly 1 or 2 at the MOST

justnspace

iTrader: (1)

remember, a dirty or clogged air filter WONT decrease MPG.

kewlliljethro

what about the tb coolant bypass

justnspace

iTrader: (1)

^i've dont the coolant bypass mod on my TL.
It's not for gas mileage. lol


HIGH temps from the coolant pass right next to the throttle body.
THus, heating the throttle body up. any air that passes through the throttle body gets heated....
remember colder air = denser air = moar POWER.

rockstar143

iTrader: (6)

To me, there's an inverse relationship between power and mpg BUT, that said, with a little more power sometimes you need less of it to do grandma driving, thus saving you money.

I got much better gas mileage on my rsx type s with 210 hp than i did in my si with 160 because I had to give her more gas to get it going.

justnspace

iTrader: (1)

Spelling mistake in my previous post.
IVE DONE the coolant mod

rockstar143

iTrader: (6)

my brain auto corrected that, didn't even see it.

redpoint

The cold air will reduce fuel efficiency in 2 ways.

Since the air is more dense, it presents the car with more aerodynamic drag. On a hot day, or at higher elevation, the car has thinner air to slice through.

Dense and cold air also means more power at a lower throttle opening. For any given opening of the throttle, more oxygen molecules enter the engine than normal. The smaller the throttle opening, the greater the pumping losses incurred by the engine. So, if you ran warm air into your intake, it would take a greater throttle opening to do the same amount of work, and larger throttle openings incur smaller pumping losses. Adding a warm air intake is a popular mod among mpg enthusiasts, although the gains from this are very slight.

This is non sequitur. If you are developing more power, it is because more fuel is being burned. Grandma driving is actually quite inefficient. Engines operate at peak efficiency near the top end of their power output, not the bottom end. That's the whole idea of "pulse and glide" hipermiling.

rockstar143

iTrader: (6)

Well, when fiancee drives, she gets much better gas mileage than me...and I like keeping the engine in the top end of the power output. I think you're comparing efficiency in reference to performance as opposed to efficiency in gas mileage.

TSXstock

Can anyone report an increase in mpg after cold air addons? ive read so many claims of increased mpg from i/h/e setups, if i could gain power and mpg at the same time, i love hondas

i know the parts will nvr pay for the saved gas but if i can have fun and save at the same time

rockstar143

iTrader: (6)

It's hard to say but overall, it feels like the car accelerates with greater ease from a stop, which is normally where you kill your MPG. When on the highway, I would say it's probably a wash since you're just doing a constant RPM.

I will say this...dropping from 85mph on avg on the highway, to 70...I saw an increase of 5MPG. Dropped to 65 and saw another 4MPG. Pretty crazy.

redpoint

A COLD AIR INTAKE WILL NEVER INCREASE FUEL ECONOMY.

People might claim that a CAI will increase mpg, but it goes against science. You must have missed this post, so I'm linking it for you here.

If you have any questions as to the physics, ask away. On the other hand, I'm completely useless when it comes to explaining magic, or wishful thinking based on concepts that rely on magic.

Wind resistance increases at the square of velocity. In other words, it takes exponentially more power to go just a little bit faster. Your observation agrees with physics. Crazy indeed.

rockstar143

iTrader: (6)

^^^Figured it was just the constant spray of extra fuel to keep it at that speed...but didn't take wind into account. Thanks!

DuckDodgers

Actually, he referenced "pulse and glide". You don't pulse, you hammer. Pulse and glide is fast acceleration to speed and the glide is allowing the speed to bleed back off. The theory is using high rev means efficient use of power...and gliding down consumes no power.