Carnewal GT Exhaust

After much (far too much) reading of the cat back exhaust threads here and elsewhere, I made a choice in modifying my '06 CS. I purchase the Carnewal GT exhaust . This is a modified version of the stock exhaust , provided by the Carnewal company, Gert Carnewal proprieter, in Belgium. Some of our UK and European Continent members have posted their reviews of the offering, so I will not rehash those findings (see Carnewal GT Exhaust review - and Just got back from Carnewal - ). However, I will describe the process of purchasing the system, as this is a little different than other third party exhaust solutions. For starters, there are no local US dealers. Additionally, you have to return your stock exhaust to Carnewal (or pay a $400 euro core charge) after you receive the system. I ordered the exhaust last week (2011.08.15) at a delivered cost of $450 euros and got the exhaust today via FedEx. I'd call that pretty fast service. The system consists of two modified stock mufflers. No instructions or other materials. And really, who needs instructions? The factory manual covers all installation and adjustments. I do think a set of header to silencer gaskets would have been a nice touch, but not a requirement as these don't seem to wear very quickly. The box looked like this: I guess I had some vision in my mind of an elaborate crate or similar packing, but it was just a double sided cardboard box with a heavy wrapping of Flemish newspaper around the connectors on the mufflers. The packaging scheme was simple, make a rectangle out of the mufflers and tape the loose corners together. No other packing was in the box, but the product survived the trip across the Atlantic unscathed. The only external difference between the stock part and the Carnewal GT is a new weld around the cat can where it joins the muffler. I did inquire about the modifications and was assured that the cat is removed. Welds look good: Gert asked how many miles my car had on it to "match" the system - I presume this meant that cars with less miles get nicer donor equipment used . My car has 61K miles, and the supplied exhaust looked similar to what I returned. So to return the core, I just mimicked the packing job and used the same box. I did add some extra bubble wrap in addition to the newspaper, and used a LOT of packing tape around the box to seal it up. It had the look of a box that had been around the block, and perhaps around the world, at least once. I had investigated the cheapest shipping option, and found that the 35" x 25" x 11" 43 lb package would ship via USPS Priority Mail International for $150 (if I printed my own label, which I did). Dropped it off and my garage space was not compromised (I have parts all over the place since the engine is out right now). I'll supplement my post once the system is installed with a video/sound clip.

I've been thinking about this system myself. I can't wait to read your findings. Thanks for posting this!

It will not be for about 2 weeks, so please contain yourself

I'm curious to hear your impressions about it. At ~$800 it seems like a reasonably economical option. Did they tell you that there is any performance gain? I suppose that the loss of one cat should offer up a few extra ponies.

Thanks for the report and photos!

Wouldn't it cost less to have this work done locally? It seems straightforward to me: scribe an alignment mark across the seam cut catalytic converter along the seam remove the catalytic converter reweld the seam utilizing alignment marks Am I missing something?

I did consider a local update of my stock system. What kept me from going this route was uncertainty about all the changes made. It is possible, and likely, that the changes are not limited to just removing the cat. A larger pipe after the cat is also possible to install with this process. I am going with the many positive reviews of the sound vs my own experiment. However, if anyone has a stock exhaust they would part with in the name of science, I would attempt to make similar changes.

Take it to the airport as carry on and run it thru the xray ;>

Are you going to add a DREAM, or some other aftermarket tip? I suggest it. Looking at my AWE tip it looks like a no brainer that it flows the exhaust better.

Yes, I have a Dream 1. I will be keeping the stock S tip unless a good deal shows up in the classifieds

As a point of information, the US postal service got my core back to Belgium in 9 days at their cheapest parcel rate: Shipment Activity *******Location ******************************Date & Time -------------------------------------------------------------------------------- Delivered ***************BELGIUM *******************************08/31/11 10:58am Arrival at Post Office **BELGIUM *******************************08/31/11 *7:34am Customs clearance *******BELGIUM *******************************08/29/11 *8:56pm processing complete Customs Clearance *******BELGIUM *******************************08/29/11 *2:19pm Customs Clearance *******BELGIUM *******************************08/26/11 *2:46pm Processed Through Sort **BELGIUM *******************************08/26/11 *2:46pm Facility Processed Through Sort **ISC CHICAGO IL (USPS) *****************08/23/11 11:39pm Facility Arrived at Sort *********ISC CHICAGO IL (USPS) *****************08/23/11 11:39pm Facility Acceptance **************NEW HOPE PA 18938 *********************08/22/11 *1:17pm Electronic Shipping ********************************************08/22/11 Info Received

Does the new setup have any of the metallic rasp the stock system produces a bit over 5k PRMs?

Great thread....I am extremely interested in Gert's system and you've answered a lot of the questions I had (I've just sent a message to Gert now asking bout any differences with the Cayman R exhaust - see this thread: http://www.planet-9.com/cayman-boxs...m/cayman-boxster-modifications/61055-cayman-r-exhaust-vs-cayman-s-question.html ) One question remains....did he use Het Nieusblad or De Standaard as packing material? Could say a lot about his politics :hilarious:

Interest level would be high for me.

"Made locally soon"...might that be in New Hope, PA??!! Chris, if you are working out a deal with Gert to be the "local" guy, I would volunteer to be your first US customer...close proximity to you, original already off the car, no 'core exchange' needed,etc...That is if Gert gives you all the secrets to do it 'his way'... Rich Gilbertsville, PA

I really don't see how this is worth it. Any muffler shop can do that.. Why the hassle of international shipping + $800?

Rich, it is not me. But Gert is monitoring this thread and if a local shop becomes part of his delivery system it will be made known on his website It depends what "that" is, doesn't it? If you want to perform your own independent R&D effort, have at it! Carnewal has an excellent reputation and Gert has figured out how to make this work well. If a spare exhaust was free and I had a tig welder and the confidence I could use it, AND I knew what to change to prevent droning, THEN maybe I would have taken another route.

Interesting. Any sound clips or hp gain? I suspect it sounds stockish with no gains for 800 bucks.

I suspect you have not searched this site for previous reviews: http://www.planet-9.com/united-kingdom-ireland-region/51851-carnewal-gt-exhaust-review.html http://www.planet-9.com/cayman-boxster-modifications/28745-987-boxster-cayman-gt-muffler.html Or taken a look at the Carnewal site: Testimonials Or searched YouTube: Carnewal GT Exhaust on a 2008 Boxster 987-1 - YouTube Carnewal - '09 Cayman S DFI with GT Exhaust - YouTube The dyno is an open issue. However, since cats are removed and flow is increased from the muffler can onwards it certainly is not a step backward.

This is what I received from Gert yesterday on both the Cayman R issue and the likelihood of a supplier in the U.S. With the first generation of 987, they already had a limited series of exhausts used on the 3.2S where the exhaust diameter of the long pipe ingoing pipe was increased with 5mm, so what they have done now with the Cayman R, is not new . The plan is to have a location in the US where they will modify exhausts. I am going to try and find a Cayman R exhaust to be used as core exchange and also offer the option to have your own exhaust modified within a very short time frame. We have a lot of shops in Europe for which we offer this service. They send the exhaust of the customer’s car and we modify in 24hrs. Dr Kareem....if it is so easy....why don't you head down to your local muffler shop and ask the first mouth breather who comes along to do to YOUR Cayman. Let us know the results. Gert Carnewal is a very well established figure among Porsche owner's in Europe. I met a guy at the Porsche dealer in Brussels who swore by the work Gert had done on his GT3....good enough for me.

Sure, send me your mufflers and 800 bucks and I'll fabricate a good exhaust for you

I don't mean to bash anyone but we have some local boys here who will do wonders with exhaust fabrications. I'm sure in the states you have more capable people too. Anyway, good luck with your purchase, I was just stating an opinion.

Easy. I did this years ago already, gut and cut. Original thread with pics is long gone now but for the price one can easily have this done themselves and save a few hundred bucks.

I too am interested. Could I do it myself, yes. I have the skills and equipment but what I am missing is the exact knowledge of what needs to be done. I do not want to reinvent the wheel so I will pay the premium to have it done for me. Now, the question about having an R exhaust for an exchange needs to be answered.

Gert has mentioned in his message (see my post) that he is going to try and find a Cayman R exhaust to modify and start the core exchange program for this model - the alternative will be to find a U.S. agent to carry out his mods on your own exhaust . I would prefer to have my own modified - it's not going to be a daily driver, so having the exhaust off for a week is no big deal - but will go core exchange if that is the option. In other words - I'm in if Gert wants to join as a sponsor and pursue a group buy.

I could live with a 1 or 2 week turn-around. I will be keeping an eye on what develops as far as a local agent or a group buy. Local for me would be 3000 miles or so!

I have a custom carnewal exhaust with 55mm inlet tubes from an early 3.2 S (compared to the 2.7/3.4 47mm inlets). I assume the topic of discussion about the R having larger inlets , implies that this gives a bigger power gain. Experience from fitting a de catted carnewal item with the larger 55mm inlets and dyno runs thereafter , suggests the pipe size doesnt give a gain. From my own experimentation to date , the primary cats and manifold design / diameter have more effect (the 3.2 S is around 2hp better than 2.7/3.4 when de catted , possibly more when cats are in place) The larger inlet pipe size into the rear silencer gives a louder sound as the outlet throat from the cat is also 55mm , so the gasses are not funnelled. The gen 2 exhausts have significantly longer and better gas flowed headers than the gen 1 cars , which I suggest is the major contributor to power gains. I would suggest if the R has larger inlets into the rear silencers than hte stock gen 2 cars its more of a sound tuning exercise than power gain. The custom carnewal exhaust I have sounds significantly louder and deeper than the standard carnewal , but still maintains the ability to avoid drone at 3000-4000 rpms , something which other aftermarket exhausts fail to achieve. I would compare the sound to that of the gt exhaust with hi flow cats as found on the carnewal web site. At higher rpms or under acceleration the sound is more race than road car.

For Sale: Carnewal GT Exhaust -Gen 1 My 2006 Cayman S had 20,000 miles on the OEM exhaust . I replaced the OEM with a SpeedArt exhaust purchased with the group buy on Planet-9. Since the OEM was sitting in the garage, I decided to send it to Carnewal 's US Distributor for modification. The modification in the US is done by Cantrell Motorsports in Kirkland, WA. They did a very quick turn around for me. I have been looking for a CS with PDK for months and of course, I found one I wanted while the OEM '06 exhaust was being modified! I received the Carnewal exhaust (my modified OEM) on Friday, Nov 11, 2011. I have not even opened the box to look at it as I was hoping to slap a new shipping sticker on it and let UPS pick it up to deliver to another Cayman exhaust enthusiast! Here are the numbers: It cost $650 to modify my exhaust plus $110 to have it packed and shipped to Cantrell. It cost me an additional $75 for Cantrell to ship it back to me. Total = $835.00 I am selling it for $650 plus I will ship it without charge if it can go UPS for $75 or less. I will include the sales slip from Cantrell. I am located in Gilbertsville, PA about 35 miles NW of Philly. Rich Devaney [email removed]

Thanks for this information. Gert is being coy about who exactly he has doing the work in the U.S.. Sure enough....just 85 miles from my place. Great offer on the GT Exhaust...but not a fit for my car.

I'm surprised that after it's been out this long, there are still no dyno results. Anyone have any idea if this is comparable to other catback systems as far as power and torque increase?

From what I understand, there aren't any claims of increases in hp or torque. Purely an aural modification.

I'm the lucky recipient of the first GT Exhaust made by Cantrell! Colin, the owner, has been keeping my cars in top shape since 2001 so was thrilled when he became the US maker of these exhausts. I'd been holding off simply because I didn't want to just throw away all that money on shipping to Belgium! Anyway, I've had it for a few weeks now so might as well chime in on the sound. I actually bought it for the added power and not the sound, but I'm VERY sensitive to drone so have been waiting to pick and exhaust for a long time. I went through several on my 2000 Boxster S and always went back to stock due to the horrible drone. So, yes, even this exhaust has a bit of drone between 2600 and 2800 RPM but even to my very sensitive ears, it is quite tolerable and most of the time I don't even notice it. The only time I've really noticed it is in 6 gear at around 65MPH which just happens to hit the magic RPM range for drone. So, I do drive in 5th to avoid it, otherwise it just gets a bit tiring. I've come to know over the years that you simply can't avoid the drone completely with a more open exhaust without having an automatic flap to close it down a bit in that RPM range, like the PSE and others have. I'm just not willing to pay the money for those units and this Carnewal GT Exhaust is well within my tolerance level of the drone and frankly the price is RIGHT! Otherwise, it has a really nice sound. At idle it sounds great, a nice low grumble, and has awesome pop pops when decelerating Screams pretty well above 4500 RPM as well. As I said, I got it mainly to compliment the other RS350 power mods. I was going to get the Cargraphic exhaust but just couldn't see spending the money on it vs Gert's. It should provide a nice bump in power. Maybe not as much as some others, but should be close. Getting rid of that secondary cat is worth a lot and whatever else they do should help even more. So, in summary, highly recommended. I'll get a dyno run with all the goodies, but I didn't do a "before" run given all the others already out there, so I'm sure it will be "worthless" to a lot of you

The exhaust is SOLD! Thanks for all the interest...this is a great site to reach out to like-minded folks. Rich Gilbertsville, PA

Great post! do you have an update on how you like the carnewal exhaust ? have you noticed and power gain or drivability improvements?

My take on the Belgian version is that there is no drone (resonance effect). Louder, heck yes! More power, "feels" like it . Better sound? Yes!