Hi Folks,

Been some time since I've posted here. I've received a few e-mails with some good suggestions with items to add to RX300how2. So I've add a few to the web site. The latest two are changing the transmission fluid and replacing the engine air filter.

Thanks to all who regurally stop by the site.

http://rx300how2.home.comcast.net/

Ed

 

It is a good site with lots of helpful info. I used it replace stock sidemarkers with clear ones.
Another performance enhancement for RX is to replace the resonator with a cold air intake air horn. I did it with $20 parts from Home Depot and gain about 8-10 hp when combined with K&N filter

 

Ed, your site has a lot of useful information, tks for the air filter site.

 

TunedRX,

So, tell us more about the cold-air horn replacing the airbox. Is it cut into the airbox somehow? I would like to try the mod.

thanks, Ed

 

Tools: 10mm combination wrench, recommended w/ rachet, scissor, stub Phillip screw driver. Optional: Xacto knife, 10mm socket and rachet
Home Depot components to build air horn: 14" Zip Tie (8 pack), 3" Qwik Cap, 3" 90 degree elbow tube, rubber Flex Coupler 3" to 1.5". Last three found at plumbing dept.

WARNING: do this mod at your risk, I am not responsible for any damage done on your car.

Steps:
1) Use RX300how2's instruction to take the left front fender well off.
http://rx300how2.home.comcast.net/side_markers.htm
You can't miss the black resonator held by two 10mm screws to the frame.
2) The front one (yellow in pic) of two screws are the most difficult since there is not a lot of room. That is where 10mm combo wrench w/ racket helps a lot. Use closed end w/ build in racket to hold the screw and patiently loosen it. The second screw is a cake. Resonator will come off easily after both screws are removed.

 

3) Connect 3" end of rubber fitting to the 3" elbow, tighten with provided steel band. 1.5" of the rubber fitting will fit into the hole that used to connect to the resonator. Turn the elbow opening toward the hole in the front bumper so it collects cold air outside of the engine bay.

 

4) There are many holes in the frame close to the air horn - now taking the place left by the removal of resonator. Use zip tie to secure the air horn, might daisy chain two zip ties to extend the length. Secure the air horn from different directions to the frame using holes in the frame.

5) Cap the intake hole behind the left front head light with 3" Qwik cap. I trimmed the lip of the rubber cap with Xacto knife but it is not necessary. Secure the cap with zip tie. This is an imporant step as the cap seals off the warm air coming from the engine bay and redirect cold air collected to the engine.

 

6) Put back the fender well, there is one screw that you can't put back since air horn takes a little space. Notice the bulge. But it is good enough to keep dirt and water away.

 

+ on this mod: 100% reversable, HP gain, intake air is colder, air stuffed in is proportational to speed, $15 in parts, (see labels on some of these plumbing parts)
- on this mod: a little more noise at idle, fender well has slight gap, another member reported more gas usage but he is using Mexican gas in high elevations - I don't have have this problem

It will take about couple days for the ECU to adjust to this mod, you should be easily butt-dyno your HP gain afterward

 

I have to take left head light off to zip tie 3" rubber cap, but if you have small hands you may not need to. Note the white zip tie holds air horn, the cap is held by a black zip tie near the bottom of the pic

 

Wow! TunedRX, many thanks for your mod and step by step instructions w/pics. May I place a link on my RX300how2 site to your link here?

Ed

 

Yes, also if anyone has suggestion. Just PM me.

 

Ed,

Haven't looked at your site in a while, nice job

We should list it as a resource on our CL lexus website links, PM me if that's ok with you and what logo / text you think we should put describing it.

https://www.clublexus.com/index.php/link/category/9/

 

Tuned,

Good to see your posting on the mod. I don't have a digital camera to show mine, but it is virtually identical to Tuned's with the exception that I have the front of a bullhorn attached to the entrance to the airhorn to scoop in as much air as I can. I also used PVC.

One other difference. Where the PVC pipe meets the adapter (a long black plastic piece with a 3 holes and curve that joins to the air box), I placed a small curved PVC piece inside and turned it toward the flow of the engine. That way, air flowing into my airhorn flows into the engine itself, not into the engine compartment. as the hole where the car used to take air from is too close to the part where the resonator hole is.

I also have that bulge on the fender, but no harm done.

I was also thining about adding the following, http://www.bmcairfilter.com/infoCDA.asp

 

Could you let us know about the curved PVC piece that you use to rediect the air flow. Also are you running the engine a little rich since the air is thinner at high elevation?