Warm air intake

[Magician]

Fred, That's great. 38mpg out of that old pinto is pretty stellar. You are certainly well above the EPA MPG ratings. I'm stuck at current MPG's until I do something Aero... curses!

[ECONORAM]

Originally Posted by Magician

Ok. Now that I effectively have proven on my own vehicle that a WAI works very noticeably well in the Winter, will it also help in the Summer? Anyone know this from testing?

On my truck, a WAI can aid summer fuel economy, as you are noticing. HP does drop a little. When I did some testing a couple years ago, I saw about a 5-6% increase. I cannot remember the member's name (now I do! Tvago), but he did some testing on a Dakota with a 4.7L like mine, and 130*F was really the upper limit for intake temps. My truck doesn't seem to like it that high, but does show some improvement with IAT above 90*F.
(Maybe my issue is that there isn't enough airflow out of the engine bay since I put in the panel kit...)

@74Pinto: Holy Cheez-its! 38mpg in a Pinto! Good job and God bless you!

[Magician]

The VX is going to get parked after this tank. I found out her friends in school make fun of the Green Bean, so I'll drive my 2000 Civic with swapped JDM B16 for a few months until she gets her drivers license. Believe it or not... I have gotten 35 mpg's with that B16 engine and short gearing. Usually about 30 MPG without hyper-miling it.
Oh... just bought the wife a used Prius... wow... what a car! I may buy another. 315,000 miles and drives like it only has 50K! I drove one with 30k miles and didn't really seem to ride any better. Highway miles certainly are easy on a car.

[s_t]

Nice work on the mileage increases

Newbie here: I've seen a few threads detailing warming the intake, and how to do it, but haven't noticed an explanation - how does heating up the air intake lower fuel consumption?

I understand that cooler air is more dense, which means more O2 per set volume to burn with the fuel, which means bigger explosion and more power output. Wouldn't more power (via cooler air) mean you can back off the throttle to achieve same engine output, saving fuel in the process?

[teoman]

The cars systems control the fueling. There is an o2 sensor and if you have more oxygen entry you have more fuel injection.

When you heat up the air you get less o2 and less fuel, you lose power but gain efficiency.

The fuel also evaporates more so you get a bit better combustion aswell.

[Magician]

Teoman hit the nail on the head. Some cars may respond a little better than others, but I will say my Honda vehicles seem to gain several miles per gallon from the much warmer air. Seems more significant in cold weather, but even in the Summer I see a decent gain.

[s_t]

Thanks. So in part it's about fooling the computer, to optimise for efficiency rather than power. We need some of the big car manufacturers to go open source!

[teoman]

Not really fooling it, it is doing its job of creating the optimum mixture (that engineers specified) and it it doing its job relatively well. No need to adjust the carburator when at altitude etc...



You could fool the ecu with an o2 sensor (wideband) and make it believe that it is burning more fuel than it actually is, this way you can get it to lean out the mixture.

And some ecus are designed for "lean burn", they inject less fuel in certain conditions. Lean burn can have ignition problems and emissions problems if the car is not designed for it.

[ar5boosted]

Originally Posted by s_t

Thanks. So in part it's about fooling the computer, to optimise for efficiency rather than power. We need some of the big car manufacturers to go open source!

Some are to a degree. There was a lot of suggestions by Mercedes enthusiasts a few years back telling Mercedes that this needed to be done for older vehicles to be able to keep them running. I think they listened to some degree - but not sure what happened after that.

With GM vehicles I notice that there has been forums like https://www.pcmhacking.net/forums/index.php where people have got into the older computers and understand them quite well.

The main problem is that it just takes perhaps a decade for the systems to reach the 'Open Source' level via reverse-engineering and by then everything else including shiny paint on your vehicle has moved on.

[teoman]

I concur that the ecus should be open source.

VW and audi ecus can be tuned with 20 usd cable. But if it were completely open source that would be better.