tCizzler

A drop in does just what the name implies, it just drops in where the factory one was... in the air box. A SRI or CAI is not a drop in, but refered to as an air intake

Menace

SRI- Short Ram Intake
CAI- Cold Air Intake
Drop in- is what you have now (The filter in your factory box)

nyr197

see below.

nyr197

I ordered a K&n drop-in filter and it should be coming today actually.. Being safe, I google-d some negative opinions of k&n filters, I found a bunch of people over at the 'Bob-is-the-oil-guy' forums
http://theoildrop.server101.com/foru...=0&Board=UBB15

Evidently they claim since the k&n 'flows' better, it allows more dirt to enter the engine, even though the oil is there.

There is even a test of 6 air filters, showing deposits allowed through on the forum there if you search hard enough.

Now I don't know if I should install this thing, it might be more trouble than it's worth. I realize there is a 2nd filter, which should capture things that manage to get by, but I don't know if it's worth it now.

Thoughts?

Spect2K3

I never thought of that or even heard of it. I mean, sure some dirt will seep through any filter and i'm sure that when you change the oil, you get rid of a lot of it that gets caught there, but i never heard of excess amounts of dirt deposits with any intake, let alone drop in filter...

maybe someone else knows more than I do

BigMURR

Well more dirt will enter the filter when it is new but as it gets dirty it actually improves it filtering ability...but restrictive to air flow as well.

nyr197

Increased flow has to translate into more particles being let through the filter media, even though it's oiled and dirt traps more dirt yada yada yada...

Personally, I don't think the gains, if any.. are worth the potential of letting dirt in that normally wouldn't enter the engine if I stuck with stock filters.

There is an entire forum dedicated to air filters over at that website, I'm going to take their word for it.

tCizzler

Increased flow doesn't necessarily mean less filtration...

K&N gets increased flow because it covers more surface area. The stock filter has about 4 or 5 zig zags in the filter surface area. The k&n has about 40 or 50 zig zags (not sure if zig zags is the true technichal term, haha) Point being, if you cut the filter element out of the center of the filter and stretched them both out (k&n and stock). Then the stock would be almost the same size, approx 12-14 inches. But if you stretched out the k&n it would almost quadruple its size to approx 2-2.5 feet. Technically K&N should and could filter better, but i guess they messed up somewhere.

Im not saying that k&n filters better than stock, because i've seen enough evidence to show that it doesn't, but all im saying is that more flow DOES NOT mean less filtration... It uses the same principle as a cone filter with all that surface area. Its just that the k&n is stuffed into the original air box

BigMURR

^^^^Completely correct there is alot of engineering that goes into making a filter it's not like they just say "hey lets use cotton and make more zags" they want the maximum surface area with a minimum amount of debris.

Does this mean it's any better...prob not but only because intake mods do marginal gains regardless of CAI or SRI or stock.

That is why I kept my stock box and just modified it to get the cold air from the bumper. Toyota and most car companies do a lot of R&D to maximize the engine's efficiency and on a N/A engine you can't expect too much.

dtycoon2003

I would be one that agrees with those negative opinions of K&N filters. I was a huge K&N fan for many years until I did a simple test. Run a K&N for 500 miles then remove the filter. Take a white cloth and wipe the inside of your intake past the filter. You will be amazed at the dirt passing the filter, and by the way, your engine is eating this dirt. Do the same test with stock filter and you won't get nearly the dirt, if any. Yes stock filters are more restrictive, but they also do their job better. Just my opinion.

willingwelli

would an 05 k&n air filter fit in an 07?

willingwelli

would a k&n air filter for the 05 fit the 07?

nyr197

I've got a brand new k&n filter still in the packaging if anybody is interested.

I went with a paper Napa Gold air filter instead.

Spect2K3

Yes, I think an 05 would fit in an 07. I don't think they changed the air intake box, not 100% sure, but pretty sure

svrTc06

I know that this is goin back a ways, but that thread that everyone is talking about, where they are showing the Drop-in filter loosing 1hp, has anyone on here acually read that entire thread?? i know i did, and the ppl who actually performed the dyno test, KillertC/GSCMotorsports, later overlayed the two dyno graphs. the graph reveils that yes there was 1 PEAK hp lose, however, thoughout the entire RPM range the Drop-in filter numbers are slitly higher....not much....but higher none the less.

here is the Stock VS K&N Drop In Filter as posted on the thread

https://www.scionlife.com/forums/vie...dyno&&start=60

Sorry i dont kno how to post pics here.......anyways go to this site and page down, you will see what i am talking about.

Menace

svrTc06 The general consensus here is that it's not worth the upgrade. Whether it lost or even gained 1hp is not significant enough to notice or make any difference in performance. Same applies to any increase you are talking about on that chart.

Spect2K3

hmmm, makes me think...losing HP and gaining dirty in the engine....

Spect2K3