Warm Air Intake - suggestions

Because its stock. Stock parts are super lame.

 

Although I have a 2.7 and not a 4.0, I do run a warm intake for better gas mileage...



...and am pleased with the 23 mpg average even with a fully loaded service truck and a lot of third gear driving on rural roads. I'm not concerned with heat soak. Injectors mixing fuel into nice hot intake air is just fine with me.

Greg

 

If you actually buy a new one in the box, it comes with a dyno sheet proving the whp gain.

 

They also don't prove your MAF will be messed up and that any off road and it's an oil lubed dirt catcher

 

I get 26 on average in mine, I do a lot of city driving, some highway. However my truck is never loaded.

From a Power Engineering standpoint;

You want the warmest air possible, air goes through air heaters and in big power plants is sucked from the top of the building (hot air rises because its less dense). The closer the combustion air is to the auto-ignition temperature (the temp. at which a given fuel will combust, I believe gasoline is something like 260 degrees C, don't hold me to that though) the more efficient the boiler will run because less energy in the form of heat (kJ, BTU, etc.) is wasted warming up the air in the furnace.

That being said, you have an IC engine, I don't fully understand how the less dense air helps fuel efficiency, Doesn't the MAF adjust for the warmer temperatures?

Like it was said before I would roll around with a light foot in a high gear.

FYI
The "prime" A/F ratio is 14.7:1 which is called stoichiometric. However, that runs too far too hot and causes burnt valves.

 

I'm not in school and don't wanna think about thermodynamics & heat transfer haha but the MAF reads the mass of the air. The colder the air, the more dense it is. Which means to keep the A/F ratio correct, it adds more fuel, which results in a "larger" combustion and creates more power. More fuel and power means worse gas mileage essentially. But seeing our trucks come stock with a factory CAI, a better CAI will produce more power but not really a lose in MPG.

But tooter runs a WAI, so the warmer the air, the less dense it is. Which means it takes less fuel to get the correct ratio. Which less fuel is better fuel economy.

At least that's my understanding

 

I'm pretty sure mine would do about the same, as my 23 is with no freeway driving at all. It's also doing a lot of first gear on steep narrow winding canyon roads. Just about the worst driving conditions for gas mileage. So I'm happy with the mileage it gets for how its used.

I'm an economy driver, and that's why my focus is only on low end torque in the 1,000-3,000 rpm range. The few times it gets floored is basically on the dyno or to make a video, and that's only for a few seconds, so I'm not really concerned.


Greg

 

There's also another gas mileage advantage to a warm air intake. The engine warms up faster and gets out of the fast idle rich mixture "choke" mode quicker.

Greg

 

I however am not a economy driver (hehe). A lot of it probably depends on my route to work, I basically coast most of the way and I'm running it around 1900 RPM

I really appreciate the detail you put into your posts!! It's helped me make future plans for my taco

 

Thanks for your kind words, Mitch.
I enjoy posting. It's way more fun than watching TV.

Just some off topic trivia...
I do a lot of coasting down steep narrow rural roads in first gear, and took careful note of exactly when the Deceleration Fuel Cut Off mode cuts in and out.

As rpms rise, DFCO engages at 1,800 rpms, and as rpms fall it disengages at 1,400 rpms. So you want to coast above the 1,400 rpm threshold, even if it means shifting into a lower gear, so that the ECU doesn't turn on the idle fuel circuit. So in a situation where 5th gear coasting falls below 1,400 rpms, it's more economical to coast in 4th gear.

In terms of economy, DFCO is your friend, because while it's engaged, your gas mileage is infinite.


Greg

 

It basically turns the motor into a giant air pump!! Good to know!

 

I did a Volant CAI + scoop and URD MAF Sensor. Didn't notice any increase in MPG, maybe slightly better performance when stomping on the pedal, but overall 'noise' was increased. If you want a great look under the hood, go for it. If you want want throw away $$ (mine install was about $500) install a CAI. And, I wouldn't waste your money on the URD MAF.

 

That's a really neato looking intake.
I'll bet it sounds awesome. Sometimes we do things just for the cool factor, and that's ok. Is that little box a URD MAF sensor or is it their MAF controller? How was it to install?

Greg

 

Hey Greg...it's the MAF sensor calibrator: http://urdusa.com/p1260198051/URD-MAF-Sensor-Calibrator/product_info.html

Installation was easy - just soldered the leads to the wires on the ECU just under the passenger kick panel. I just keep the black box in the glove compartment.

Yah, intake does look great and definitely more 'throaty'....helps along with the Borla catback too in terms of great sound.

 

Thanks.
I just emailed URD to see if it will work with my 2.7.

My Flowmaster exhaust is so loud, I can't hear my intake any more!

Greg

 

you like that intake? i was thinking bout getting that one

 

Warm air intake you say....

Simple, route a small pipe off your header right into the intake tube.
Problem solved. Won't get any warmer than that!

 

Old cars used to do that...
They ducted hot air from the exhaust manifolds right into the air intakes. The intake manifold vacuum operated valves would automatically open for colder air under heavy acceleration. The pic is of a 1978 Chevrolet Corvette...

 

I did it on my recently hailed-to-pieces Honda Fit, in the winter months. The car warmed up faster than the ridiculously long time it took without the mod. Gas mileage was marginally improved too.