Warm Air Intakes

[k8crd]

Is anyone running a Warm Air Intake at this time of year?

If you are, can you please show some data on how well it is performing!

Outside air temp, intake air temp, mpg and pictures of your installation would be nice!

Paul
Michigan - currently -3 F

[Hateful]

I didn't try collecting data, but I reach operating temp of 195 degrees in about 1.5 miles. I did grill blocks shortly before that. It used to take 3 or 4 miles to warm up before, and it hadn't gotten cold yet. I prefer to discuss mods after the fact, so these folks don't get a chance to talk me out of it.

[WRXGuy1]

This may be a bit of a noobish question, but is the reason you do warm air intakes to keep the intake temperature up, which in turn uses less gas? I know colder air uses a richer mixture of gas, but is better performance wise.

How much of a gain do you guys see in the winter time with your warm air setups?

[flapdoodle]

Performance does not necessarily equate to FE. For horsepower, you want a denser charge mixture, hence the use of blowers and turbochargers. The latter often uses an intercooler between the turbo and intake to reduce the temperature. But for mileage, we are more interested in a more complete burn.

If my intake air heater is not functioning in the winter the FE is awful.

Bill

[Rower4VT]

Has anyone actually done a more scientific test of FE gain from WAI? I.e., have you done FE test before and after, in similar outside temp conditions, without changing anything else? Does it increase FE noticably bothin the winter and summer, or only when it's cold outside? Thanks.

[slurp812]

Originally Posted by geoff5093

This may be a bit of a noobish question, but is the reason you do warm air intakes to keep the intake temperature up, which in turn uses less gas? I know colder air uses a richer mixture of gas, but is better performance wise.

How much of a gain do you guys see in the winter time with your warm air setups?

more oxygen = more fuel. So with warmer air theres less oxygen, and less fuel. Its like having a slightly smaller motor...

[gto78]

I personally believe that cold air intakes cause worse gas mileage. BUT Cold air intakes are more efficient, you have a better supply of air to "work with". I truly believe that installing a cold air intake will increase the fuel mileage "IF" you take the IAT sensor and mount it somewhere that is sensing the usual hot air the car always used before. Basically your just tricking the car into running lean, and then it's up to the O2 sensor to bump up the mixture just enough to prevent burning out an exhaust valve.

[Snax]

I think you are forgetting that it takes a specific amount of energy to turn the motor over. At operating temperature, the amount of energy required is constant at idle. It still requires the same amount of energy no matter what to overcome that internal drag regardless of what temperature the intake air is. So to maintain the same idle rpm with a higher intake temperature, more throttle - and fuel - would be required to meet the energy needed, so that is clearly not where the savings come from.

The extra efficiency actually comes from improved atomization of the fuel. This results in a more complete and clean burn, releasing more of the energy available from the fuel in the cylinders as opposed to in the exhaust stream, thus less fuel and air are required. A similar effect is seen by heating the fuel prior to injection.

[s2man]

Snax, I agree with all you said except one small bit. Yes, it takes the same amount of energy to run the engine regardless of the air temp. And yes, as the air warms, and its density lessens, we will need more throttle. to let the *same* amount of air in (in weight, not volume). But, we won't need more fuel to maintain a stoichiometric ratio with the less-dense air.

[kamesama980]

Originally Posted by s2man

But, we won't need more fuel to maintain a stoichiometric ratio with the less-dense air.

no, you need more fuel with more dense cold air. running the IAT sensor in a warm place with cold air actually going into the engine will result in lean running by the intake temp/volume math. the O2 sensor then compensates enough to prevent burnt valves.

with the concept I agree but ultimately whether the IAT or O2 sensor make it stoich, it's stoich and you aren't running lean anymore. if you want to inject X amount of fuel into the engine (as if WAI) you may as well shove in a matching amount of air so you don't burn valves. lean is just a reference to the A/F ratio not the total amount of gas. That being said, different cars have different results from this type of mod. some saturns respond VERY well to it. some cars it makes no difference.