There are some differences between the four... some have 2 mufflers only.. some four... meanwhile others use 2.5, 2.75 or 3" OD piping.... not to mention some X designs are done internally covered by a muffler meanwhile others are done outside with 2 or mufflers... some are custom made mufflers with unique sound and the ability to control it as the mufflers are made meanwhile others use high quality mufflers ....
All though they are all some sort of X design there are differences when you look behind what goes into making them and what is used...
BTW, BBI does one too...
best
markski

Mark... will you be testing db level for your Systems?

Steve,

The full race 3 inch unit is loud, make no mistake. It sounds intoxicating and is what I will get if I am ever able to part w/ my EP.

Sean... problem I have is that Noise is now a Major issue in UK/Europe... they are so, so strict now, most tracks are 105db max, some are 102db, we are instantly turned away if we don't meet the requirements... I now that some of the US circuits are also now starting to take this very serious and I can see this effecting future sales for some of your guys (certain circuits)
I can live with resonance, cabin boom and even a not so nice sounding exhaust note... my priorities are Lightweight, 105db or under, max freeflow as possible. I have mentioned this to a few vendors now and have passed on how they sound test with noise meter at the circuits here in UK/Europe.
It will also give a good indication to 6speed members here how loud these units are... Example I run the Europipe Quiet and this comes in at 102db on meter and the Europipe is overall relatively quiet.
Circuits will have various ways of testing, Static Test and Driveby Test, Driveby is usually quieter, the Static is usually done with noise meter held between 75 cm and 100 cm away from tailpipe and at a 45 degree angle (so it's not direct in the flow vortex)... they ask what the cars Rev limit is, I just say 6500rpm and they ask me to take it to 4500rpm (usually 3/4 of it's limit) This is the test they run at a few of the circuits in UK.

This is a great thread for those of us w/ a stock car looking at some aftermarket upgrades.

I don't want to get real wild on this car but I would like a new intake ( filter system and hoses ), exhaust system ( something that gets more HP and loses weight while sounding great and allowing me to hear people talk and my radio play when I want ), flash ( 80HP or so ), and suspension...

well maybe I do want to do a lot?

The cool thing about some of us is that we can make you a custom exhaust per your specs... 2.5",2.75, or 3" OD... custom mufflers, different cats or no cats... and even do custom tailpipes... when you see in person a hand made per order exhaust you then appreciate the difference... I did...
I am speaking not just about my system... I mean all who make them inhouse in the US.... I have seen good stuff from US tuners...
How do the European off the shelf exhausts compete with this ? They weigh more, cost more, not finished nearly as well... ( seen a few high end systems )... And usually most of them are found on www.Alibaba.com done by the Asian market... I seen some $7500 titanium exhausts sold by high end P car tuners for example... i wonder if it cost them more then $1000 to produce. A few others as well.... Mind you the Europeans are not immuned from cheap Asian labor
You get what you pay for as they say... I seen crap as I also looked into production overseas... Its soooo cheap and soooo tempting... If i would tell you guys which popular P car exhausts I have come across that are made in China you guys would not believe....
I pay my Fabricator more an hour then the Asian sweat shop pays to make the one piece.. and its probably made by a 14 year old girl.
happy new year to all and my comments were not directed towards any tuner/shop by no means...
best
markski

Can you run w/out cats and not get he CEL to come on? I don't want them if I don't have to have them. Now, if they actually help the performance then fine. On regular cars they don't. So I would rather have just pipe and muffler. I like the duel tip as well.
From what lil I have read here, I should get the intake first. Then do the exhaust and flash at the same time. I say it in that order do to $. Am I on the right track?

This is the point I was trying to make earlier on - The driving enjoyment with our cross-flow vs. every other exhaust I have ever tried is un-equalled. And I feel the exact same way - every single time I drive my car, the X-cellerator exhaust brings a smile to my face. No other system I have owned or used has sounded nearly as good and the best part of it is that there is no getting tired of it - every drive is great, even a trip to the local store is fun listening to the exhaust. It is one of those intangible features that specifications do not address. Once you experience this kind of enjoyment with an exhaust, you really realize what you were missing before and you wish you would have done it sooner.

We have an extension that has prevented the CEL on my car when running catless, but it has not been widely tested. My gut instict is that it would most likely work for you, too. Running catless will increase the performance, but also the sound. It's louder, as the cats act like a muffler.

Personally, I would do the exhaust and flash first. An intake alone will not do much for you. We offer exhaust / flash bundles using the EPL flash, which is an excellent product and by purchasing both items together at the same time, you save some money. If you would like more informatiom, PM or email me with your car specifications (turbos and any mods) and I can provide you with a bundle price special for EPL flash and SpeedTech exhaust.

Here is a picture of our new mirror polished dual tips on our X-cellerator crossflow exhaust -

It probably is not as odd as you think. We have been doing a lot of research and have found the 997tt knock sensor to be far better than the 996tt sensor. Yes, we believe there is a problem with knock sensing with the 996tt. They are microphones which are not the best solution.

When you start changing things on the 996tt you are changing frequencies and widows that the knock system listens to. I am not saying this "is" an issue with the X, but it could be. I know increased boost, cams, increased bore size, etc. is an issue.

Have you ever bothered to ask why the 996tt bend rods and lifts heads at 800 hp and the 997 does not?

We are designing a system that allows for the adjustment of frequencies and windows to avoid just such an issue.

That looks real good John.... I like it...

Most catless exhaust throw a code... but we can turn that off with a flash....
mark

Funny thing is that some tracks use DB meters on one side of the track so the veterans just bolt on a 45 degree piece of exhaust pipe to route noise away from the sound meter

Yip and last year noticed cup cars using a bolt on muffler (see if I can find a pic)

I was under the impression that the 997 TT comes with a much more advanced air/fuel system (dual MAF, better fueling, etc..) as well as a stouter bottom end.. ? Couple that with a more advanced DME and you can see how that extra 100HP is better supported in the 997 platform.

The stock 996 Air/fuel system even with larger injectors is at the ragged edge of fuel delivery and air measurement by about 650-700 HP... hence the need for aftermarket MAF, Injectors, FPRs and fuel pumps at the least. is this not correct?

I'm curious to see how tunable and durable the 2010 TT will be with higher compression and 3.8 liters.

Getting a bit off topic, but VW is planning a below Boxster level P car and has vowed to start accelerating the slow progress of P cars in general. I hope this means 600HP cars aren't far away. At the current rate of 20-50 HP per generation we would have to wait for the 999 to see 600HP cars.

Man I thought Mark was kidding - he's not! http://www.alibaba.com/trade/search?SearchText=996&Type=&CatId=120215&IndexArea =product_en&Country=&ssk=y&sq=y I saw "alibaba" and thought it was a joke - nope! lol

CJV, I'll be very interested in what you guys have figured out and release for sure. I think it will be awhile before I have those worries but still!