So I bought my wife a 2007 RDX and I'm looking at the engine after changing out the spark plugs with Denso's and I realize the air intake is incrediably restrictive. I know K&N sells a cold air intake but its well over $300 as compared to a K&N panel filter which is $40. So I decided to go with the panel filter but remove the black plastic air tubing prior to the air filter assembly. I then took the RDX for a drive and noticed the turbo is much more noticeable and it also pulls a little harder. I think I will take the difference in $ and put it towards the Hondata reflash. I'll have to post some pictures when I get a chance, but I think anyone who has looked at their engine bay area has probably noticed the ridiculous factory air intake silencer attached just prior to the air filter assembly.

 

and removing the silencer made you notice the turbo sound more, seemed to be doing what it was supposed to. And it probably pulls harder cause of the K&N...........idunno, i'm just sayin.

The reflash will definately be a Hooot!!

Congrats on the purchase.

 

Well, I'm trying to attach the pics I took today but I have no idea what "the url address" is to the pictures. God forbid I can jsut attach them. Anyway, the pictures are worth seeing and I show how the air silencer intake is 2.5" inside diameter as compared to 3.25" inside diameter for the inlet of the air filter box.

Wspy, obviously the rdx pulls harder because it's getting more air. Try not being a smart ass. It's impolite. The entire point of this post is to explain how to perform a simple mod and save around $300 by doing it yourself.

 

Let's see if this works...

 

http://yfrog.com/5p20100615pics03410j
http://yfrog.com/1720100615pics034378j
http://yfrog.com/0i20100615pics03437j

 

No prollem man, I know what you're sayin. The K&N is the major contributor here.
What you should probably look into now is attaching some form of pipeing to the intake of the filter box to prevent injestion of underhood engine heat.

 

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I don't know how familiar you are with Turbo engines (you sound like you are knowledgeable about cars), but they run pretty hot. By removing the part of the air intake that's supposed to bring in cold air you have effectively shot yourself in the foot. You "feel" that the car "pulls harder" but that's just a placebo effect you get, enhanced by the extra noise generated by the turbo....let's say that the KN gave you a few extra horses; that's not going to make a big difference (put it in terms of percentage).
Good thought, terrible execution


And probably slowly cook the engine overtime....

 

By removing the silencer of your stock intake box your not going to make any power but loose power . It sounds nice but not beneficial when I got my Rdx Dyno the first time I had done the exact same thing and found I was loosing around 8hp from just sucking in hot air . This is also not the first time some one has posted they have done this .

 

The entire point of this post was to compare a DIY project which cost little more than $45 and a little sweat equity to a K&N Cold Air Intake (CAI) which cost over seven times the panel filter. It's a simple job which may appeal to some people that don't have a lot of money or who like to tinker with their cars.

DIY versus K&N CAI. That's it, and no it's not going to "cook" my engine. The compressed air coming out of the turbo is much, much hotter than ambient underhood temps prior to it going through the intercooler. Furthermore the factory air silencer intake, at 2.5 inches is located directly behind the radiator which is full of very hot liquid.

Crazycated, by your logic the K&N CAI dyno results is bogus then because they show a 8.77 horsepower gain and that conical filter is located essentially in the same area as the air filter box intake (which is 3.25 inches).

I do know the turbo is now breathing in air easier, because the intake is less restrictive, and I can't see how a plastic tube that is three quarters of an inch smaller in diameter and has a ninety degree bend in it and located directly behind a radiator is going to be better than what I have now.

R*D*X*, thanks for posting the pics.

 

if you could do without the plus in sound, i think sticking with just the drop in K&N engine filter is the best way to go, and probably the safer route. Ive used one since i had my RDX, have noticed consistent differences vs going stock. Most noticeable are increased throttle response, sweeter turbo spool, and a little more oomph at higher RPMs. On top of that, my mpg increases about 1-2 MPG across the board. I take the K&N out for the winter months and have done so since 2007. I notice differences. Some people like to refer to these gains as placebo effect - whatever. the drop-in K&N is good enough for me without screwing with anything else and leaving it completely stock.

Also, you are comparing 2 totally different filters & their respective results. The K&N (CP-E) are, like you said, conical but completely exposed to suck in all air possible. very different. presently you still have your 'covered' air box, not exposed to all air possible, and still somewhat restricted suction. The reason why both K&N & CP-E have increased results is due to a completely different intake, not just the fact that it may be in the same area as the stock 'box' or using somewhat similar air. what the silencer is doing is moving the location of suction to where the air is coolest under the car exposed to air rushing underneath....how i understand the removal of the silencer is now the duct that is sucking in is further into the engine bay drawing it away from the cooler air.

Overall, I for one think the K&N is perfect while not screwing with the car in any significant way. By removing the silencer, you have def increased turbo sound but any other gains i think are doubtful.

 

At no point was I talking about the k & n or any other filter or intake . Just the plain facts that if you remove the silencer there will be some loss of horsepower . Now like I said not sure if your doing it for some HP increase or just to have a nice sound which I am not putting down just saying you will loose horsepower plain and simple and I am not saying this because I read it or heard but when I dyno my Rdx and that is what the dyno machine showed when I removed the silencer of the stock intake box unless the dyno is lying .

 

I guess you are right Those people making and engineering CAIs wasted their time, they could have just not do anything, like you did....

 

You guys really should proof read your posts. I had to read each one of them numerous times to see that you guys are again talking in circles despite my last post which plainly spelled eveything out.

I hope someone out there is enjoying my post and "improvement" rather than spewing negativity and doubt. F!

 

Habu,

Thanks for trying.

 

This is all so flippin hillarious!!

Alright guys, these are the facts;

The K&N drop in panel is the cheapest intake mod and will give you some performance increase.
If you remove the intake piping to the stock airbox (silencer) you will get a louder intake sound but you get a decrease in performance!
The K&N performance intake kit gives a larger increase in power/performance plus the louder intake sound and comes with a heat barrier to reduce engine bay heat to the conical filter.
The CP-E performance intake system gives the most increase in power/performance and positions the conical filter far enough away from the engine so that engine heat is not much of a factor!

These are the facts people. Enough said

 

I read somewhere that someone with an STi did the same thing and also had a loss in power.

 

"I read somewhere that someone...." Really? You can't get a little more specific than that?

I was all done with this but because it won't die, so I'll reinject some more life into it.

All engines work on sucking in air. The more air the engine is able to consume the more power it will make. I.e. "There is no replacement for displacement", etc. You can also "cheat" by adding a turbocharger, supercharger, or nitrous to increase the airflow.

(I hope everyone agrees with me up to this point, if not you're hopelessly biased.)

So anyway, since the engine is consuming more air, again MORE AIR (albeit slightly warmer air) now as compared to before (I'm referencing my setup in this), it is making more horsepower (albeit a very small amount more). I showed probably cause for this by submitting the pictures with the measured air silencer intake and outtake. The K&N CAI and CP-E probably make more horsepower as compared to my current setup due to the elimination of the corrogated tubing by replacing it with an aluminum polished tube and a conical air filter, but (and here is the but that everyone just has a total freekout about), it is a minor amount of horsepower because the actual relocation of the intake (meaning where the air is drawn into the conical filter as compared with where the air is drawn in on my setup now) is within such a short distance of each other and they are both invariably drawing in underhood air.

So, to conclude....the setup in the wife's RDX is now drawing in more air . More Air. Air.....more of it as compared to before thereby making more power as compared to before.

Please don't let the fact that you spent $350 on a CAI cloud common sense. Let the hate continue.

 

 

It's not hate, it's pointing out that the claims you are making are not true.
You don't know whether the car is making more horses, you just think that it is because it's louder. You think that if you follow the "more air equals more power" doctrine, regardless of the way you do it, you will make more power, but it is not true. Turbo engines loose power if it's too hot....You know what, go to Saabnet.com, a BB about Saabs....if you know anything about turbo charged cars you will know that Saab knows what's up. just do a search about air temperature and power loses....
Now you are pi55ed off because nobody believes you....
Initially I gave you the benefit of the doubt, but now I just realize that you are just a stubborn person that has to always "be right".
While you are at it, why don't you just remove all those restrictive exhaust pipes and boxes, it will be free too and increase horse power, right?

 

A few corrections/additions if I may,

 

http://www.streetunit.com/PhotoDetai...ctCode=ARDXXWI

Go to the above attached link and look where the air is drawn into the engine on the CP-E intake and then look at where the air is drawn on my existing setup. The distance is within inches of each other meaning they are both drawing underhood air.

It's not hate, it's pointing out that the claims you are making are not true.
You don't know whether the car is making more horses, you just think that it is because it's louder. It's drawing in more air now as compared to before so it is making more horsepower. I don't understand why you don't accept this simple concept. You think that if you follow the "more air equals more power" doctrine, regardless of the way you do it, you will make more power, but it is not true. Actually it is. That is the principle behind turbocharging. Compressing air and forcing it into the engine. Turbo engines loose power if it's too hot.... This is true, that is why many turbo equipped engines come with intercoolers to cool the air after it is heated by compression. You know what, go to Saabnet.com, a BB about Saabs....if you know anything about turbo charged cars you will know that Saab knows what's up. I don't need to talk to Saab, I already know that compressing air causes it to increase in temperature. I just do a search about air temperature and power loses....
Now you are pi55ed off because nobody believes you....
Actually I'm not upset, I am a little surpiresed that some people will defend their purchase of a $345 dollar "Cold Air Kit" which is literally an inch from a DIY setup. Initially I gave you the benefit of the doubt, but now I just realize that you are just a stubborn person that has to always "be right". Nope, just right when the evidence proves I'm right and not blinded by bias.
While you are at it, why don't you just remove all those restrictive exhaust pipes and boxes, it will be free too and increase horse power, right? Nope, engines work on backpressure also. I can also explain that to you to if you'd like.

 

Ok Habu have you put your Rdx on the dyno and I will answer for you no . Have I dyno my Rdx yes with stock intake and with no silencer tubing and intake so what I know are pure facts not what I think or what I read and the bottom line is removing the tubing to the stock air is loss of power and not defending any aftermarket part just giving the simple facts .

 

Geez..I give up!
Maybe we should just let it be.

Habu..... u de maaan!

 

Ok Habu have you put your Rdx on the dyno and I will answer for you no . You are correct, I have not. Have I dyno my Rdx yes with stock intake and with no silencer tubing and intake so what I know are pure facts not what I think or what I read and the bottom line is removing the tubing to the stock air is loss of power and not defending any aftermarket part just giving the simple facts .

As you know there are many variables that can affect one dyno pull to the next, but having said that I like your last line "not defending any aftermarket part just giving the simple facts".

 

Yo, if you like what you did to your RDX, thats great, no one is beating you up over it. The issue is that there are members on the board who are trying to HELP you out; they have the dyno, they have the stats that show that what you did may hurt the car not help it. Why are you so adverse to listening to this advice?

If the sound increase and everyhting makes you happy, thats all you can ask for, there are just ppl trying to point out that it may be hurting performance based on their experience, not becaues they are hating on what you did.

if i was in your situation, id actually be open to the comments posted here because i would not want to diminish performance, regardless of what my beliefs may be. Also, if performance/sound is what you seek - why not go the CAI route and spend the 300 knowing full well that you are actually getting an increase in performance with the proper filters etc

im neutral to what you did - if you like it thats all that matters, but if im staring at numbers (or if someone is telling me such based on their dyno) thats info pretty hard to deny

 

Habu, you are actually right, I am sorry, I, and everyone else here, am wrong, we just don't know what we are talking about it. Enjoy your free mod and the increased horsepower that came with it.

 

Let's just leave it at we agree to disagree, unless someone else stirs the pot again which I think we can all agree that we don't want that.

 

I wont agree to that....I am agreeing with you!!! MORE POWER CAPTAIN!!!!

 

More power indeed, my friend. More power indeed.

 

Total cold air. Inexpensive. (Some drilling required.)

 

Nice, but you should paint it something neon.

 

Hahahahha

 

That's perfect it's dirt cheap and no hot air problem this should give us 100hp to the wheels . LOL

 

If I could...I would. I don't keep a hyperlink to everything I read. I think if you search hard enough, it might have been even discussed in an old thread in here from someone with the same idea. IIRC, it may have something to do with resonance. FYI-I just did the K&N panel filter and didn't want the noise of a 4-banger with a CAI.

 

.................Stop it man! Your killing me!

 

I did the same thing on my Mazdaspeed miata(stock turbo miata) a few years back before getting an intake and also lost power, it sounded good though. It's just a fact that if you take away the part of the stock intake that funnels cool air from your bumper to your engine that you will be sucking in hotter air, and lose power. Even with an intercooler if the air your starting with at the intake is hotter than normal then the air after the intercooler will also be hotter/less dense, the cooler the air being sucked in the more air the turbo is compressing and the more power it makes. I'm not comparing an aftermarket cold air intake that uses a heat shield, i'm just saying stock vs that setup you will have less power.

There's no agreeing to disagree, you're just wrong, and you seem to be the only person in the entire thread that doesn't get that. I understand that you're proud of what you did and that it may sound good but there's nothing wrong with being wrong from time to time, everyone is so just accept it and if you like the sound and feel it's worth it then keep it the way it is

Not trying to be a dick, just saying how it really is.

 

Air density = pressure/(gas specific constant*Temperature)

More air = cold air
Less air = hot air

 

Just purchased an Acura (2007) TL Type S, I'm looking to replace the headers, and the exhaust, but not to sure what to get, I want to keep the Factory exhaust tips, don't want nothing real loud, just a nice sound(don't want to set off no alarms)! Any help would be appreciated, this site came highly recommended! I will be putting in a cold air intake!

 

Probably lost power due to the intercooler getting heat soaked by not having air moving across it .