Cat Bypasses Installed
#46
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Thanks for the info, Steve. That clears things up for me. From what I've been reading, this seems to be the first mod recommended for the car. Let me know which way you go (pre-fab vs. DIY), and how it works out. I'm not too handy with a welder, but my old man sure is, so I might go the DIY route if it's not too overwhelming.
#47
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Kevin,
I've got a far more serious problem than you... my wife wants that TT to be QUIET! I tried disconnecting the mufflers (a simple, 15-minute experiment) to see if I wanted to go with a muffler bypass instead of the cat bypass. Nice, agressive sound, a little "bark". About a 20 HP (butt-o-meter) improvement. But my wife HATED it. So now, I need Scott to bring his car around to have my wife listen to a cat bypass and see if she'll approve that sound. Once I'm past that hurdle, I will investigate further. BTW, a third option is to have a good muffler shop (perhaps your Dad) make up the cat bypasses by hand. My guy said he could do it for $300 -> $400, complete.
I've got a far more serious problem than you... my wife wants that TT to be QUIET! I tried disconnecting the mufflers (a simple, 15-minute experiment) to see if I wanted to go with a muffler bypass instead of the cat bypass. Nice, agressive sound, a little "bark". About a 20 HP (butt-o-meter) improvement. But my wife HATED it. So now, I need Scott to bring his car around to have my wife listen to a cat bypass and see if she'll approve that sound. Once I'm past that hurdle, I will investigate further. BTW, a third option is to have a good muffler shop (perhaps your Dad) make up the cat bypasses by hand. My guy said he could do it for $300 -> $400, complete.
#48
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Bob,
Did you ask Bob Holcomb about his trick CAT bypass system he can make out of your exisiting CATS?
I'm curious if he is still doing that.
Rick
<a href="http://www.993tt.com" target="_blank">www.993tt.com</a>
Did you ask Bob Holcomb about his trick CAT bypass system he can make out of your exisiting CATS?
I'm curious if he is still doing that.
Rick
<a href="http://www.993tt.com" target="_blank">www.993tt.com</a>
#49
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Rick,
No I didn't. I want my cats intact so I can swap back in a couple of years.
Steve,
The Racers Group looked at the Fabspeed kit and their reaction was not good. First, it uses standard exhaust pipe. Not stainless by any means. Second, if you got a quote for $2-300. then that is great. TRG was estimating most of a day to cut and fabricate the two pipes (which will require a lot of fitting), and then welding all the flanges on the old cats, the new pipes, and the stock pipes. I decided to go with the pre-built.
No I didn't. I want my cats intact so I can swap back in a couple of years.
Steve,
The Racers Group looked at the Fabspeed kit and their reaction was not good. First, it uses standard exhaust pipe. Not stainless by any means. Second, if you got a quote for $2-300. then that is great. TRG was estimating most of a day to cut and fabricate the two pipes (which will require a lot of fitting), and then welding all the flanges on the old cats, the new pipes, and the stock pipes. I decided to go with the pre-built.
#50
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</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by ca993twin:
<strong>
I've got a far more serious problem than you... my wife wants that TT to be QUIET! I tried disconnecting the mufflers (a simple, 15-minute experiment) to see if I wanted to go with a muffler bypass instead of the cat bypass. Nice, agressive sound, a little "bark". About a 20 HP (butt-o-meter) improvement. But my wife HATED it. So now, I need Scott to bring his car around to have my wife listen to a cat bypass and see if she'll approve that sound. Once I'm past that hurdle, I will investigate further..</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">There are definite perks to being single... Freedom to modify car at will being one of them.
Sounds like the ol' axiom remains true on the cat-bypass question --> you get what you pay for. The $500 option is sounding less and less attractive to me.
<strong>
I've got a far more serious problem than you... my wife wants that TT to be QUIET! I tried disconnecting the mufflers (a simple, 15-minute experiment) to see if I wanted to go with a muffler bypass instead of the cat bypass. Nice, agressive sound, a little "bark". About a 20 HP (butt-o-meter) improvement. But my wife HATED it. So now, I need Scott to bring his car around to have my wife listen to a cat bypass and see if she'll approve that sound. Once I'm past that hurdle, I will investigate further..</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">There are definite perks to being single... Freedom to modify car at will being one of them.
Sounds like the ol' axiom remains true on the cat-bypass question --> you get what you pay for. The $500 option is sounding less and less attractive to me.
#51
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Gents:
I'd like to ring in here a moment with some things to consider.
We recently installed some cat bypass pipes from Cargraphic on a client's TT and they didn't come even CLOSE to fitting correctly. The flanges and angles were all wrong and we had to cut away all of the flanges, section & re-aim the pipes then reweld the flanges back on.
This operation consumed over a day at $ 70/hr and I cannot recommend to anyone that this is a great idea with these products. If I were doing this again, I'd build my own on the car in either 321 SS or Inconel. I've seen FVD stuff with the same fitment issues so Caveat Emptor on these things. If you have someone who can fabricate them for under $ 500, IMHO, thats a bargain, If the material is correct.
FWIW, we flow tested 100 cell cats against the stock 400 cell ones and they both flowed 354 cfm, right on the nose. Tough to justify at $ 2800/pr. Further, the 100 cell cats failed to catalyze the exhaust properly and the car threw "Check Engine" lights every 50-60 miles with codes from the secondary oxysensors. If you choose different cats, use the 200 cell ones.
I'd like to ring in here a moment with some things to consider.
We recently installed some cat bypass pipes from Cargraphic on a client's TT and they didn't come even CLOSE to fitting correctly. The flanges and angles were all wrong and we had to cut away all of the flanges, section & re-aim the pipes then reweld the flanges back on.
This operation consumed over a day at $ 70/hr and I cannot recommend to anyone that this is a great idea with these products. If I were doing this again, I'd build my own on the car in either 321 SS or Inconel. I've seen FVD stuff with the same fitment issues so Caveat Emptor on these things. If you have someone who can fabricate them for under $ 500, IMHO, thats a bargain, If the material is correct.
FWIW, we flow tested 100 cell cats against the stock 400 cell ones and they both flowed 354 cfm, right on the nose. Tough to justify at $ 2800/pr. Further, the 100 cell cats failed to catalyze the exhaust properly and the car threw "Check Engine" lights every 50-60 miles with codes from the secondary oxysensors. If you choose different cats, use the 200 cell ones.
#52
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The FVD cat bypass pipes that I had were made by either Bishop or Gillett? for FVD. I do not recall which I received, but the fit was perfect. There were no installation issues with the FVD product. I assisted in the install, so I know this as a matter of fact.
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991.2 GT3 RS Weissach Racing Yellow
991.2 Turbo S GT Silver
991.2 GT3 Chalk (Manual)
2022 Cayenne White
former 1972 911T white, 1984 911 3.2 Targa black, 993 cab white, 993TT arena red, 993TT silver, 996TT speed yellow, 991.1 GT3 white
www.speedtechexhausts.com
info@speedtechexhausts.com
Testimonials SpeedTech Exhaust Videos facebook
#54
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It sounds like Cargraphics and FVD may have more than one source for their bypass pipes. It's real frustrating when something like that doesn't fit.
Rick
<a href="http://www.993tt.com" target="_blank">www.993tt.com</a>
Rick
<a href="http://www.993tt.com" target="_blank">www.993tt.com</a>
#55
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it seems everyone is getting varied success in keeping the CEL light at bay.
what do i need to do to keep it away... without removing the other protective features from the ecu?
will i get a set of flames poping out at the track?
what do i need to do to keep it away... without removing the other protective features from the ecu?
will i get a set of flames poping out at the track?
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