invest in a K&N air filter

[oil pan 4]

The problem with gasoline engines is the more you increase static compression, the cylinder is scavenged more completely. The engine tries to run more efficiently and make more power, but then the throttle gets closed more, lowering dynamic compression, making it less efficient again, because the is no demand for more power.
Thats why compression increases on gas engines net little to no measurable cruising improvement.
If you run a 8:1 compression ratio or 10.5:1 to 1 and reguardless of elevation your dynamic compression is always going to be between 3 and 4 to 1 as you drive down the road.
You need to understand the isobaric expansion process. You have up to 2 horsepower worth of wasted power that can be used to pull air through an air filter or restrictive intake during normal driving.

The idle air control has nothing to do with this.

If you want to play "cram more air into the engine" and have it actually do some good get a diesel. Where more air and clean air filters actually means something.

[mcrews]

Originally Posted by oil pan 4

If you want to play "cram more air into the engine" and have it actually do some good get a diesel. Where more air and clean air filters actually means something.

[Cobb]

What we need is someone with a lean burn capable vehicle like a honda to try the air filter switch a roo. I bet with a clogged or simulated clogged air filter lean burn wont be sustainable.

Maybe Ill try wrapped a bag around my kn cai to see how it effects my mpg. Should have zero effect, right?

[Frank Lee]

http://www.fueleconomy.gov/feg/pdfs/...02_26_2009.pdf

If anyone can conduct a better test series than this... DO IT.

Note the results.

If you like, there's more:

http://www.autospeed.com/cms/article.html?&A=111486

Here's another test, but they don't get into the power and fe effects:

http://www.nicoclub.com/archives/kn-vs-oem-filter.html

[user removed]

Funny how a few of the tests showed better mileage with the clogged air filter on the modern efi systems, aka a governor. They restricted the air filter so much on the Lucerne, it sucked the filter out of it's position.

regards
Mech

[mcrews]

hey frank lee,
your first link is the report that I post in the beginning..at #43.....

[Cobb]

Oh, well since the government performed the test we know that went well. It was on a few older vehicles and the test was conducted in 09. It actually showed the dirty or clogged filters gave better mpg, but the conflusion didnt mention it.

Since with the insight ima assist is partly based on petal position I am expected it to actually go up vs down. I pointed that out earlier in this thread and even included photos to show, but guess no one saw it?

[Cobb]

Read both articles. One said its the plumbing to the air box, if not the air box itself. The other said basically that the better filters are more restrictive and a guy who owns a diesel watched them put the filters on a testing machine for filters and filtration testing.

When I quit noticing an improvement Ill quit buying them.