wspy

You can go ahead and wait for the Quote" ATLP is suppose to be around 400 at the most probably close to the same craftmanship and you can use it on a stock exhaust", but you will probably be waiting un till ..... mmmm let me think???...... oh, next to never

Just a bit of reality check here; No one else is goin to take the time research and money to produce a downpipe and 2nd cat delete! Its just that simple, and you can call around and check it out for yourself. We all have been waiting from about Aug '08 for this piece and finally some one has step up to the plate and prduced the DDP for us all.

The DDP is labeled " For off road use Only " because it is not CARB legal.
During testing, there is a substantial increase in whp & torque, the most any one mod for the RDX has produce!
On the stock ECU the AFRs are very safe at mid 14's in cruise and 11.0 at WOT. Testing on the Hondata ECU will be coming at a later date! It is expected to be very safe on the Hondata also!
Gas mileage will increase to an average of 27 -30 mpg.

The check engine light has been illuminating at times and a solution is currently being researched.

RDXturbo07

any official dyno numbers with the downpipe? Mustang or dynojet

Mr Marco

With all due respect, this is just too much money. It looks like a nice product, and we should pay a little extra for the R&D it took to bring this to market, BUT...Even the most expensive STi pipe is only $525. Don't get me started on the substantial increase...
SAVE YOUR MONEY

InfamousJamous

Wow that is a lot of money, but then you do get the mid-pipe and 3" all the way.

Kaze informed me that HT's is stainless and 3" in 2.5" out which might be better for the long run.

I support both projects but am torn between the two

bluecarbonfiber

im gonna bite my lip on your comment dont wanna upset people more then they already are

Kaze66218

I glad you said that, the .25 inches of overlap don't add too much in terms of exhaust turbulance, confirmed that with Magnaflow: Tech dept.

I was told by HT as well they are looking at how the D-DP is gonna do, before they even begin to invest into fabricating ATLP dp's. Again, I spoke with both HT and Don and neither is a bad product, and this is a shangri-la 'ish developement, here to day, gone forever tomorrow.

Bottom line, Don's DP is as tangible as it gets. While it lasts

bluecarbonfiber

^ you said it nicer then i would of =)

TruckerBomb

ok, so I should buy one ASAP?

I'd like some more reviews from users on the MPG increase, to me, that's the most attractive part of it... The HP is a very close second!

bluecarbonfiber

^ if you have 800 burning in your pocket so hot that your balls are sweating.. then get it

any bigger DP is gonna help the gas mileage..

mrgold35

Why would Acura build in a flaw that decreases HP/TQ and MPGs with the OEM CAT/downpipe? Maybe better emissions or they didn't want the RDX to outperform the other Acura brands? I can see a RDX+hondata+downpipe nipping at the heels of 2012 TL sh-awd for a lot less money.

bluecarbonfiber

its a conspiracy =)

InfamousJamous

Tangible is right. You can't get it elsewhere at the moment. Looking forward to more road test details.

TruckerBomb

So I'm confused... Does this setup cause a CEL or not? I'm almost at 70,000 miles and seriously contemplating grabbing this... but I don't want a CEL...

bluecarbonfiber

per post #81 it does..

which is why this is for off road use only

wspy

You know guys, I now realize why chaps such as Pang_Co etc apparently refused to mass produce a downpipe for the rest of us!
These guys work on their own cars and know about automobile performance benefits, drawbacks, and the consequences there of.
They also don't want to be bothered with all the remarks and opinions of some of the members that is inevitable in a medium such as this!.......
Its a darn shame if you ask me.

Here it is, that you have someone that has taken the time to put in the work and spend the money to develope a product that we've been asking for for so long, not for the profit of it but because he saw the desire for it and being a motorhead himself saw the denefit. I for one can't thank him enough!

Soo..

These are the facts............

The down pipe (DDP) will increase Hp anywhere up to 35hp as seen in the past by other fellows. There will be no dyno figures published so don't ask! Torque increase will be comparable also!
Due to the removal of both cats there is an increase in mpg to a usual figure of 28 -32 mpg highway!
This is not an easy piece to install, best done by someone with experience!
The engine check light will most likely be triggered (few have been very lucky to not have it trigger) so consider yourself not so lucky! There is an electronic fix for this in the works!

Another fact is that no one else is going to spend the time effort and money to do this again.....and you may think that I'm blowing allot of hot air when I say that but.... I really don't care

Due to reasons that us "old guys" can't be bothered to deal with, these pipes will soon be discontinued. So............

TruckerBomb

Thanks for the info! Looks like I'm scrapin together the $800 ASAP!

OhRDX

I can't bite my tongue any longer. this place may be the MOST misinformed forum I have ever seen. This guy has got id right, though he is being nice.

I am personally working with the group that is developing this, and helping to move this forward.

I can personally vouch that there is more R&D going on then any of you can understand.

I've personally worked with Audi turbo engines for more than 10 years. This is BASIC stuff to anyone with a turbo motor.

Yes, these are not CARB legal. likely, any aftermarket part isn't. "for off road use only" can you speak legalese?

Props to both Ron and ATLP for stepping up and making this happen. I've been working to do the same for a long time. goev the guys money and props for taking the risk of developing these products and helping out the community.

PM me if you have any questions or comments about my post. I will be active from this day forward.

TruckerBomb

I have -NEVER- done any performance mods to any of my cars. So I'll be the first to admit my ignorance to even the basics!

So far I've liked the advice I've been given. I do believe this downpipe is going to be the first performance upgrade I ever do. I should be able to come up with the money within a week.

Question: What would the results of just doing the downpipe and not the second cat delete? Still get a MPG increase? About how much? (assuming 1/2) What would the HP increase be (approx) of just the downpipe? Is it even worth only doing half the job? (I'm really trying to avoid a CEL!)

These may seem like stupid questions to most of you who've been doing it for a while... and I've got a little bit of common sense... but sometimes, what you think will happen, isn't reality. I really appreciate the answers to my dumb questions!

SinCity

I hear you. But the reality is that the marketplace for Subie/Evo/etc... is much larger thus more competitive. Until another company steps in, you will have to pay the "tax" if you want the product. We should consider ourselves lucky at this point that someone has spent the time and money to bring this part to the marketplace.

If you think this is bad, headers for my C63 range from $2500 to $4500 while Vette and Mustang headers are under $1k. Talk about tax!

OhRDX

all good.

The downpipe is the biggest restriction by far. Out side of that the midpipe will make some difference, but as you go further back (exhaust/muffler) the gains will be smaller. The basic design of the downpipe itself gives me a headache. Why, oh why woul Acura design it this way?

I would guess the downpipe alone isworth a solid 20-25 hp. The bigger gain will be felt in how the turbo will spool up and how quick revs will go.
This will be a great improvement over stock. With Hondata it will be better.

JCRDX11

So does this mean with just the down pipe - it won't throw a cel?

08rdx

I want to purchase one but my only problem/concern would be that Check engine light. That the only thing iam afraid of having that cel on. Would that problem be fixed soon?

OhRDX

Like anything in this world there is no guarentee.

Basically, this is what is happening:

The downpipe will remove the cat and open the breathing up. The o2 sensor will know there has been a change in temperature/velocity. The o2 sensor picks up mostly temperature of the exhaust gases. If they are lower than the set threshold then everything is ok. If they seem higher then you CPU will step in and start making changes to the fuel/air and try and get things under control. The car will likely not be able to and throw a CEL.

With the restrictions removed the hot gas will hit the o2 sensor quicker. The best way around this is to add a fouler. This is a small pipe that goes off on an angle of the pipe that puts the o2 sensor farther away from the pipe to allow the gases to cool before the o2 picks it up. The size of the fouler pipe and the distance away are what can change to make sure the o2 sensor picks up the gases in the right "range".

Ambient temperature, humidity, altitude can all play a part in this.

To add another factor to this other mods can play a part in this as well. For one thing, many report the Hondata reflask gives them an increase in mpg's. This can be true because the reflash leans out the fuel mixture, less fuel/air ratio. This is good for fuel mileage, but leaner a/f ratios burn hotter. So its good for gas, but can be probelmatic to push the temps higher close to where the o2 may jump in. An intake can do the same but not nearly on the same scale.

Cliffs: there is no easy answer. Other mods and location can play a part in how the o2 sensor picks up readings. The real anser is that there is no "one size fits all" measure for this. Until Hondata writes software into their programs to get around this its more trial and error based on the above criteria to make it work.

wspy

Thanx for helping out with explanations OhRDX

With just the second (rear) cat removed; There will be no possibility of getting the Check Light, and gas milage will not increase! Fact

With just the front cat (primary) removed i.e. the DDp downpipe installed, the possibility of throwing a Check Light is 90%, depending on many variables! Mechanical fixes (fowlers) don't always work (one is actually installed on the Downpipe)! Electronic fixes are way way better and this is what we are working on! The electronic fix is way more expensive but hey, what can i say about that You should get some mpg increase with just this part (downpipe) installed but this has never been tested and won't be by us, so take your best guess on that.



On a side note: This is the first time that a Jig has ever been made for the production of a downpipe for the RDX! That being said I am quite sure that if and when you decide in the future that you would like one of these, give Don a call and something can be worked out forthwith.

Mr Marco

You can't claim a hp increase and then not back it up with a dyno result from a reputable shop (especially at over $20 per hp).
If you post a thread here on AZ, you can bet you will get opinions and questions. Take it with a grain of salt, otherwise go post on AW . Additionally, 48 years is not old. I'm 44, and young at heart, just a bit too fat.

Thanks! Very true. This is part of the reason I get smoked by WRX's.

wspy

And guess what dude, we can claim anything we want on here, its just for you the reader to sift through the crap I don't need to post any dyno graph to know that this is the highest hp/tq single mod that there is for the RDX out there (any DP would be for that matter). Spinning the tires at 15mph says allot yeah?!
And the "old" reference was merly due the fact that we've been at this tuner/performance deal from when....... well lets just say over 30yrs

Mr Marco

Fixed

wspy

Next!

Mr Marco

wspy

So you're now pasting my quote from another thread eh!

Glad you like it

Next!

Joe Las Vegas

Only the upper pipe would be good to replace, because of the big restriction, that way you still keep the stock cat in the middle, and only lose one cat, and won't give a cel and won't stink like an 18 wheeler.
Getting rid of both cats is over the top and creates problems, hp increase is nice, but what about the loss of low end torque, low end tq is nice to have when daily driving the car.
IMO, this mod as it is i good for off road/track only, to make a good street mod, only the top pipe would be needed, as to lose the restriction in the S pipe design and lose the upper cat, then have it connected to the stock midpipe where the second stock cat is, no cel, increase in hp and low end tq too, better fuel economy, it won't stink like hell, and it won't cost a small fortune, under $300 would be nice.
If you guys did that, they would sell like hotcakes.

wspy

Joe, your analogy is somewhat flawed in that;

1. By removing both cats you don't loose any low end torque on this vehicle. It actually increases due to the fact that the turbo is now spooling quicker (RDX quick spool technology)

2. Even if you were to just install the downpipe (i.e. remove the first cat only), you will still have the high probabilty of setting the check light because the 02 sensors are all conserned with the primary cat and have nothing to do with the secondary cat.

3. The removal of these cats does not cause this "stink" that I have heard people on here talking about. My secondary has been removed since '08 with no diference in exhaust fume scent!


Once the electronic fix for the o2 is sorted this will be a win win modification

Mr Marco

^ In your defense (wspy) I can agree with you on the removal of both. You might as well take them both out as any restriction on this setup should go. This is not what causes odors.
And in all honesty I hope the mod works well and that you can get more people on board, eventually the price will fall and then I can afford to get one too!

wspy

Zeen Iyah

awoc

Wow the price is ridiculous! I would buy the upper pipe if the quality is better and the price is lower.

I have a tig and can make the flanges. Does anyone have the upper pipe and cat for me to make a jig? PM me if you do.

Joe Las Vegas

1 & 2: ok, I didn't know about that, but for #3, removing both cats will not only stink up the air so much, you wouldn't wanna be within 50 ft of it, and it will also be nasty for the environment, cats were inventing for a reason. Now, saying that removing both cats wouldn't stink it up, I'd like to know how that could be avoided, I know it's only a four banger, but it still is an internal combustion engine, a hi-flo cat would be a much better option IMO, or keep it stock in the midpipe is good too and less of a hassle to make.

wspy

^ Joe, what exactly are you referring to when you use the word "stink"? Because when you remove the cats the exhaust fumes 'smell' the same.

Joe Las Vegas

I removed the cats on my V8 hemi RT, thinking the same, not only did performance remain the same, but the exhaust fumes were so bad, i felt like I.was being gassed by some toxic chemicals when I was within 50 ft of the car.
I couldn't even run the car in the garage, not even for a few seconds, I had to back it out right away it was so toxic.
I ended up buying magnaflow hi-flo midpipes/cats.
You mentioned earlier the second cat was removed and it was not stinky, implying you still had one cat on, did you ever try it with no cats on at all?

wspy

Ok, you're referring to increased exhaust fumes! Understandable in your case.

Different engine so different results

Joe Las Vegas

Still not gonna be clean.
Do the mod, or gut the cat you still have in your RDX and report back.
I hope somebody will do that mod soon so we'll know the pros and cons.
I would only do this mod for the upper pipe to lose the restriction, but I would leave the mid pipe/with stock cat intact, they should do that option too, making it so that it bolts on to the stock midpipe.