Joe@Fabspeed

Fabspeed Motorsport USA wants to thank all of you who purchased sport catalytic converters/catbypass pipes and we are sorry if you had any fitment problems. We have installed these sport cats in-house with no problems, but then we deal with occasional fitment problems from customers and dealers. The factory parts have many points of attachment and the jigs/fixtures are very, very complicated.
Some good news for 993TT enthusiasts. Fabspeed has completely redesigned and innovated a new revolutionary combination 200 cell sport catalytic converter/catbypass pipe systems with Indy car Formula 1 style V band clamps for all 993TT and 993TT S and 993GT2 cars worldwide. These new systems allow 100% perfect guaranteed adjustable fitments and allow the 993TT owner to run sport racing catalytic converters and/or catbypass pipes and also switch back and forth in less than 20 minutes.
We have completed development and we are still in the testing phase. These parts offer more power and sports car sound than DANSK manufactured units that ALL the German tuners sell by a big margin. These work and FLOW better than any USA remanufactured/reconditioned factory type systems with inserted 100 cell race cats. Each individual 993TT sport cat/catbypass pipe system comes in three parts; the 200 cell sport cat is connected via two V-Band clamps to allow interchanging to catbypass. These pipes enable a step-by-step, systematic install with variations for better fitment. More information will be released as we complete testing.

WHB Porsche

Sounds interesting. Is there a particular price point you're trying to hit?

TT Surgeon

Looks like a nice system.

eclou

Just as an update. I have had these units on and never got a CEL until I de-packed a set of stock mufflers. The modded stock mufflers and cat bypasses then gave me a CEL for the secondary O2 sensors indicating too high a flow thru the cats. I reset that CEL 3 times and then the CEL never returned. My OBDII scanner indicated all the sensors on the car were "ready" save for 1 O2 monitor and no engine codes whatsoever. I just passed TX OBDII (plug-in) state inspection today with no issues.

Barney1

Oh you had the stock mufflers.. Thats why in the beginning no CEL... How does it sound with the new gutted mufflers??

gary11

bumperettes!! they have to go surely you have euro bumpers available in us?

eclou

The gutted mufflers are only slightly louder at speed. The idle is a bit more coarse and I am not sure I like it as much as just the stock cans. I am also unsure now if the muffler mods increased the flow enough to set off the CEL. I think it might actually be the Sunoco 104 octane gas I put in it. The Sunoco GT plus has a fair amount of ethanol in it and it is described as having increased oxygenation in the fuel compared to a stock fuel. I think it may be the excess oxygen byproduct which may irritate the secondary O2 sensors.

TT Surgeon

Try fooling the secondary 02 sensors with some extensions, fvd sells them, might work.

eclou

The extensions would be a great idea except the O2 sensor bung on 1 of the bypass pipes aim the sensor at the block, so I would have to counter sink the wire end of the sensor into the crankcase....

Barney1

Thanks to Fabspeeds GREAT workman ship....

Barney1

Was the 104 fuel leaded ?? If it was that is why you got the light... The lead clogs the 02 sensors..

LAT

Eclou; what is there to modify in a stock Turbo muffler they are a U shape tube with some perforations. I doubt they flow much less than a solid pipe.

eclou

Sunoco GT plus is unleaded.

The stock mufflers I cracked open really are a straight thru design. Probably not much restriction

LAT

I have a set of Dansk Sport mufflers for the 993TT and all they do is increase the tubing diamer to increase flow. Their tubing is 60mm, what is stock?