Which intake would show most fuel efficiency gains?

[99kleansi]

Originally Posted by Frank Lee

I think you might be nuts.

Here we go with this guy and his ten year old cardboard again.....

[suspectnumber961]

Originally Posted by crxski

You can remove the pre filter piping and add in something custom to draw air from out side the engine compartment, using ABS tubing, or flexible tubing of some sort pending the side and shape currently used.

I've used flexible tubing for air ducts previously and it has worked well, just need to seal it (tape) to the current piping, if you can cut the current piping that will work too. The main thing is to have the pipe inlet front facing. IF you could get a velocity stack on the end of it you would be set but that might cost you$.

Since if you drive for mpgs...you are not coming very close to the upper limits for flow for your stock intake...so not much would likely make a diff?

I might just remove the intake tube before the airbox and put in a K&N filter to reduce restriction slightly....at the reduced flow rate at cruise rpms.

But the throttle plate does the major restricting at cruise?

[mwebb]

Frank Lee has the most accurate answer here .
the correct answer is....
NONE OF THE ABOVE , CHOICE C ,KEEP YOUR ORIGINAL AIR FILTER AND AIR DUCTING AND AIR BOX FOR BEST FUEL ECONOMY .

despite the huge sums spent to falsely claim and imply the opposite
k & n Air Filters DO NOT IMPROVE Fuel Economy
and they do promote early engine death due to influx of dust and dirt and other assorted doo doo that most other automotive air filters prevent from entering the engine .

the EPA and IATn have done extensive testing showing that there is no Fuel Economy gains to be had by replacing a dirty air filter with a clean or no airfilter - stock air boxes will most likely provide better flow than anything available after market so do not waste your funds on the crap sold by the scam artists , here is a way to check if your aftermarket filter actually is flowing as well as or better than "stock" http://autospeed.com.au/cms/A_111109/article.htmlauto speed article

in the summer warm air will provide a slight gain over cold air , heated air in winter will provide a larger gain over ambient temperature air

between the throttle body and the cylinder head ;
intake manifold runner length and diameter can be sized to maximize flow at the rpm used most often to improve fuel economy , Intake Runner and Peak Torque Calculator
use this or one of the many others out there for the values

Originally Posted by suspectnumber961

So with a 03 Ford Zetec engine...considering the just about even cold air/warm air tests...I'd be better off just removing the whole air intake tube and installing an OEM style K&N filter to reduce pumping losses from intake restriction?

Some claim mpg gains from the K&N OEM style and less tubing for the air to run thru can't hurt....would be drawing warmer air from under the hood though....

[suspectnumber961]

Good link to the Autospeed article...Browser Warning

So GENERALLY SPEAKING the most effective mod would be to leave the OEM paper filter alone...remove the snorkel and open up the intake on the bottom of the filter box...reducing pressure drop by maybe 9" water and providing minimal warm air in the process.

"in the summer warm air will provide a slight gain over cold air , heated air in winter will provide a larger gain over ambient temperature air"

....have seen no proof of this...but it is what I suspect is the case.

If you look at this graph...I drive at around 2K rpm for mpg gains...so ANY MODS will probably be almost ineffective...but might show some gain on the rare occasion when caution is thrown to the wind....




I like to do mods...but don't like wasting $ on them...good to know which direction to go in....