Hi,

This is David Borla from Borla Exhaust www.borla.com. We are in the process of designing a race exhaust system/headers for the Cayman S and I wanted to get some feedback from the Cayman S community on what you guys like and don't like about the currently available exhaust systems as well as what you'd like to see us offer. Any feedback would be greatly appreciated.

Thanks,

db

 

Hi David,
As an installer what I am looking for is a good quality fit. The have been a couple of systems that I am not happy with how they fit or how they are braced. For Example one company, (who shall remain nameless) offers and exhaust for the cayman that the extension pipes from the cat barely get any bite into the muffler system. The mounting seems to be substandard and doesnt fit around the muffler sections correctly requiring you to fab!!!ricate your own spacer system for the brackets they supply.
Having been an fox chassis mustang enthusiats (before I discovered Porsche), i love the crack you get from your products and can't wait to get some information about your systems and hear them..
I will PM you my dealer email. I would be intrested in seeing what you come up with.

 

Let's see... Things I don't like about the current systems available...

AWE: Fit is excellent but they look like mini trash cans...
Fabspeed: Hangs down too far compared to other systems...
BB: Excellent design, EXTREMELY loud but tons of resonance...

That's about the extent of my CS exhaust experience...

 

hey David , im assuming if you develop a cayman exhaust , it will also fit 987 boxsters as well . if not , could you tell me if a boxster exhaust is in the pipeline .i've used your catback system on mustangs and felt it was the best quality system for the money . thanks in advance , Vlad

 

I'd suggest you ask the question over on caymanclub.net as they have the most experience with cayman exhaust systems and several exhaust artices you could read to get up to speed on what else is in the market right now.

 

I'm not sure this comment applies to your system since you call it a race system, but one limitation many of the present systems have is that they have retained the stock cat location in the header. This allows for easy hook up of the O2 sensors, but makes the runners very short. I'd like to see a system that retains the cats, but puts them further back in the system so that longer runners can be used. The downside of this is that some sort of O2 sensor extension cord would be needed since they would be located further back in the car.

Dave
'06 CS

 

Thanks for this Dave, this is an important topic with much misinformation being passed around. Please give me a minute to shed some light on the issue.

The dealbreaker is that the cats are welded to the header so the only way to keep the factory catalytic converters is to cut them off the OE header which makes it 100% illegal on the street. As a result, I'm not sure there's any reason to retain the factory cats. If the cats were clamped (like the standard 997) it would be possible, but it is federally illegal to cut and weld factory cats.

Here are the EPA guidelines

"When Replacement of Converters is Allowed – Replacement converters may be installed in the following situations: (1) if the vehicle is missing a converter; (2) if a state or local inspection program has determined that the existing converter has been lead-poisoned, or damaged or other wise needs replacement; or (3) the vehicle is beyond the applicable vehicle warranty (e.g., five years or has more than 50,000 miles and a legitimate need for replacement has been established and documented).The third situation normally would include only plugged converters or those damaged to the point where unrepairable exhaust leaks are present. Documentation of the need for replacement must be made by the installer and includes such information as the customer’s name, address, make and model of the vehicle, vehicle mileage and the stated reason for replacement. These records must be maintained for a specified period"

As you can see, there is no provision for replacing cats for performance reasons and in each instance listed above the owner must provide a stated reason for replacement and documentation to back it up (the installer is ultimately liable as well and must have similar documentation). Furthermore, even if you have a good reason to replace your cats and have documentation to back it up, the only legal cat replacement is the use of OE equipment. Even so, the moment you cut an OE cat and reweld it to an aftermarket header it is no longer legal. Therefore, retaining the factory cats on an aftermarket header for the Cayman is just as illegal as totally removing them.

As far as we can tell (and we would like to have an open discussion with you guys regarding this), the only option is to keep your OE headers and exhaust intact so that the car can be returned to "street legal" status at any time.

If you cut the cats off the factory header the car can not be returned to stock unless you buy an entire new OE header/cat setup.

Keep in mind that there are 2 aspects to passing emissions, a tailpipe test and a visual. Rewelding the factory cats to an aftermarket header may allow you to pass the tailpipe test but you will not pass the visual.

To summarize the issues here; Factory cat replacement is only legal if the original cat failed and you must have documented proof of this failure. If the factory cat fails it must be replaced with the same exact OE cat in the same exact configuration. Cutting and welding OE catalytic convertors is illegal.

If it's illegal anyway, why keep the factory cats?

Thanks for your feedback and insight.

db

 

In my state, there is no tailpipe test anymore. If OBDII is happy, the DMV is happy. That is why I'd prefer having a cat with before/after O2 bungs. There may be a visual inspection, but I don't think a DMV tech is going to notice if the cat is non-stock or has moved in position.

I understand what you are saying about the federal regs, but I've never heard of anyone enforcing them. There are quite a few aftermarket systems out there for a variety of vehicles that use high flow cats that are non-factory.

Dave

 

Also, to clarify - in my original post I wasn't proposing maintaining the factory cats. I just meant that I would like to have cats present (in a different location) so that the CE light is not on and I can pass inspection.

 

Unfortunately, since the cats are welded directly to the header it's not possible to pass inspection if you alter or replace your factory headers.

Or to put it another way, per EPA standards it is not possible to have street legal aftermarket headers for the Cayman.

Simply having cats "present (in a different location)" is not legal and you will not pass inspection unless the inspector makes a mistake. Accordingly, removing the cats alltogether is no different than to "have cats present (in a different location).

If you cut off your OE cats and weld them to an aftermarket header you are making a huge mistake because not only is your aftermarket set-up federally illegal but you have now also ruined your OE header. When it comes time for inspection you will have to buy an entire new set of headers and cats from Porsche and be able to prove that your original cats failed a previous inspection or you will be fined.


I understand that this is confusing but for clarification the bottom line is that AFTERMARKET CATALYTIC CONVERTERS ARE FEDERALLY ILLEGAL FOR STREET USE. In order to be street legal, the OE cats must be in place, in the original locations and all welds surround these factory cats must be in place as well.




Sorry to be the bearer of bad news.......

 

These statements are definitely true but it's up to you guys if you want to rely on inexperienced inspectors or the non-enforcement of regulations. Borla Performance strongly recommends that you hold on to your stock headers and exhaust and make sure that they are installed on your vehicle at the time of inspection.

Since aftermarket high flow cats are just as illegal as totally removing the cats alltogether we have elected to go for the most power and eliminate the cats. Since they are all "off road" or "track" systems that are not legal for street use (whether they have high flow cats or not) why not just go for the least restiction?

db

 

I understand the federal regs. What I was trying to tell you is emission reg enforcement in various states does not match federal regs to the letter. The features of an exhaust system I am interested in is shaped by the reality of how inspections are performed where I live. Fortunately, there are vendors out there that realize this and offer most of the features I want. I am sure there are potential customers that are fine with no cats. I'm not one of them, and was just offering my opinion. I thought that is what you were asking for.

Dave

 

This is a great forum but to obtain input from Cayman owners you should try Caymanclub.net That site is Cayman specific and has many members into modifying their car.

 

It is what I have asked for and I thank you for taking the time to respond. My questions are not intended to offend you and I hope that I have not done so. I'm just trying to understand your needs and I would like to have a better understanding of why aftermarket cats appeal to you, particularly if you understand that they are illegal.

From what I gather (and please correct me if I'm wrong), you feel that you will be able to pass an emissions tailpipe test in your state with aftermarket cats and that the inspector will not visually pick up on the fact that the header is an aftermarket part? Is that right? And although the cats restict flow and adversely affect performance, it saves you the trouble of having to put on your stock exhaust parts for inspection?

Please let me know and once again I apologize if I have offended you.

Thanks

 

David, most states don't have a visual inspection for smog. Cali does and a few others, but that's it. Here in Colorado, many counties don't have emissions testing at all, and the ones that do, don't do a visual. As long as the car passes the particulate tests they're happy. In which case, putting any cat anywhere is fine.