ObiDon

It took awhile to get the correct part but I have replaced the air filter with the K&N unit. It still goes through the stock air box, but so far I am not convinced that the other units offer anything better. If you want a quick boost in HP and MPG this works. I had change the Muffler a few months ago with a Raven and this helped the output side. This K&N filter has now helped the intake side. The problem I had was getting the correct filter. If you look it on the K&N website the correct number for an RX is #33-2145. The guys over at O’Reilly told me that that filter is to small, and ordered the #33-2052. Perfect fit. I recommend it. Bottom end got stronger.

leebro3

Thanks Obidon,

I was going to order the TRD air filter for my RX because I could not get my hands on a 33-2145 K&N air filter. Everybody told me the filter was on backorder or something like that. I'll check the 33-2052 air filter out.

PlanetAudioRX

so the 33-2145-1 wont fit?, is there any way it can?

ObiDon

I never saw a 2145. But if it is to small it could let bad stuff into your engine.

Daddy-O

I just got my K&N High-Flow Air Filter. Advance Auto's computer said 33-2145...I told'em "Screw that ******, gimme the 33-2052."

It fit beautifully. It was a snap...I just dropped it in, and vroooom!

My RX accelerates smoothly and quickly, but it's nothing truly remarkable or even more noticeable than with the stock filter.

I thought I heard a bare increase in engine noise, (more throaty than anything else) but no complaints there.

Hey, I bought it for the reported mileage increase, so I filled up my gas tank and reset the trip odometer. It's looking good so far...I'll report results over the next few weeks.

spinteews

nice job guys!

if you guys want tho, theres alwasy the weapon-R intake

but hey, trd or k&n filter will do fine also

Lexmexico

I was able to fit the 33-2145-1 model in my air filter. I was a little difficult to close the cover, but I managed. The Toyota Air Filter did not last even a month in Mexico City's smog. However, this little K&N unit has been giving me peformance for the past few months. Before, my car was virtually choking going up hills. A definite improvement.

commack4

According to k&N they have replaced the 2145 with the 2145-1 which should apply to models 2000 on. Prior to that they recommend the 2052

Daddy-O

K&N Mileage Report

Well, 1st tank gone with my new K&N FilterCharger.
All city driving this time.

I'd characterize my city driving:
At least 75% @45 mph or less
Stop lights every few blocks to few miles
Right-turn on red
All posted speed limits 55mph or less.
*No stretches of driving over 4 mi without traffic control (Lights/Signs).

Was averaging 19.1 mpg in these conditions
This tank avg: 20.9mpg
- A 9.4% increase

Also, during city conditions, I'd never gone more than
330mi. before the gas light came on. This time: 359mi.

While some folks talk about performance increase, I'll
admit I don't floor it much. I believe that would probably
negate any gain.

Next up...2 trips to Maryland in the next 2 weeks.
At least 700mi round trip each, so I'll have more to
report soon.

Daddy-O

Oh, yeah...This was with Regular gas (87 Octane).

Daddy-O

K&N Mileage Report #2

Well, 2nd tank gone with my new K&N FilterCharger.
All Highway driving this time.

I'd characterize my city driving:
At least 75% @55 mph or more
Little or no traffic control (Lights/Signs).
Right-turn on red
All posted speed limits 55mph or more.


Was averaging 23.5 mpg in these conditions
This tank avg: 23.5mpg ~ No Change

Speed limits- NC 70mph, VA 60-65mph, MD 60mph. Light traffic,
so little/no drafting available (We love our NASCAR).

Cruise control for most of trip set@ 68-78mph.

One thing I noticed...At 75mph (3000+ rpm) and above,
mileage really drops off. I mean it sucks! Geez, into
the upper teens.

Could it be a breathing problem? Too much backpressure?
Is this the point of diminishing returns?

I am confident that I can average 25mpg, if I can keep it
under 70mph, but I'd end up becoming the pain-in-the-***
driver that I hate when on the highway.

Next up...One more trip to Maryland on Friday...On vacation
until June, so no reports until my return.

Daddy-O

Oh, yeah...Again, this was with Regular gas (87 Octane).

aroydii

Thanks a bunch for those reports... can't wait until the next. I've begun "doing research" on the RX b/c my wife and I are interested in getting one and this type of consumer tests (even if they are somewhat informal) are hard to find if they even exist.

btw, do you think increasing your octane would help the gas mileage? the engine should make adjustments and be more aggressive with timing and such, right?

Daddy-O

After I get a decent sized baseline
with 87 octane, I may try an upgrade
and measure it again.

There's a thread in this forum,
"Regular gas!?"...Check it out.
You'll see opinions on that topic.

Definitely choose the RX 300. You'll be
glad you did (Your wife will dig it, too).

Handogen

Regarding the #33-2052 K&N Air Filter for the 99 Lexus RX300, where is the best place to buy one? I went to the local auto parts store (Checker) and they told me it would be $51 and it was on backorder.

I checked several websites and found it for $43-$47... include shipping and it's over $50 again.

I know this is a great product and will probably outlast the life of my car, but is there a better, cheaper place to buy one?

-Hando