Who has cat bypass pipes?
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Anyone have the Fabspeed High Flow Cats?
My fabspeed exhaust is great, but a tad quiet. I'd be interested in the High Flow cats if a) they improve sound b) don't throw a cel. A HP gain would be a bonus but I don't really expect to feel one.
My fabspeed exhaust is great, but a tad quiet. I'd be interested in the High Flow cats if a) they improve sound b) don't throw a cel. A HP gain would be a bonus but I don't really expect to feel one.
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if anything, you'll get the most gain out of the high flow cats vs mufflers or headers. they're just very expensive. you shouldn't get a cel as you'll still have a cat upwind of the 02 sensor. i doubt you'll feel it, but most tuners i've talked to said out of the three exhaust mods, the high flow cats give the most.
Originally Posted by kem
Anyone have the Fabspeed High Flow Cats?
My fabspeed exhaust is great, but a tad quiet. I'd be interested in the High Flow cats if a) they improve sound b) don't throw a cel. A HP gain would be a bonus but I don't really expect to feel one.
My fabspeed exhaust is great, but a tad quiet. I'd be interested in the High Flow cats if a) they improve sound b) don't throw a cel. A HP gain would be a bonus but I don't really expect to feel one.
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Joined: Jan 2004
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Originally Posted by AsianImage
all my questions answered in one post....I will leave my NA 996 exactly that...NA. Thanks!
evoms intake
header
mufflers
giac flash
lwf
for my style of driving (wringing the engine out up high in the tach) it was worth it. for others, it might be disappointing becasue all the gains are high in the rpm range... still noticeable for regular street driving though. it was totally worth it on the track too.
dynapac runs showed a best run of 277rwhp. that's about 318 HP with 13% driveline power loss.
if you are expecting a large push from these mods don't bother and get a supercharger or TT.
if i were to do it again, i would do it in a heartbeat... i would've also added sport cats though
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Originally Posted by deputydog95
not for nothing bruce, but how can you stand the header, cat bypass, and muffler combo? i had that setup on my car for a day. it sounded like ****. way too loud and raspy, and not in a good way. more like a honda civic with a big rusty hole in the muffler 
i think the cat bypasses are way too much if you are using any other exhaust mods.
as a point of reference, my stock 996 made 275 rear wheel HP on the before dyno run. after the supercharger and header install, it made about 425 rear wheel hp.
i think the cat bypasses are way too much if you are using any other exhaust mods.as a point of reference, my stock 996 made 275 rear wheel HP on the before dyno run. after the supercharger and header install, it made about 425 rear wheel hp.
275 rwhp before the SC hmmm. that means the mods i did on my 3.4L brought it up to 3.6L peak HP. i ended up with 277 rwhp with the bolt ons and the dyno runs were on a more conservative dynapac dyno.
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Originally Posted by LUIS95993
Deps car was the loudest, worst sounding Porsche I have ever heard in my life with the cat bypasses.
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Originally Posted by karlooz
i guess "to each his own". this 996 with cat bypass sounded awesome at the track. sounded like a cup car.
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I have Fabspeed Cat-bypass and really like it. I have newer, porsche replacement exhausts (I think same as an '02) on my 99 and it sounds awesome with the bypass pipes. It is much louder, but no resonance. Screams like a caup car, well almost 
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Originally Posted by LUIS95993
I am sure that other catless 996's sound great. Deps car with his combination (Suncoast headers & Cargraphic exhaust) sounded like *** though. Raspy like an 89 Integra with a fart can exhaust.
SC QUESTION: I am gong to SC this car eventually. Will the cat bypasses be an advantage after the blower goes on?
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Originally Posted by John Romano
SC QUESTION: I am gong to SC this car eventually. Will the cat bypasses be an advantage after the blower goes on?
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Originally Posted by karlooz
here's my take. this is what i've done to my car before the supercharger, not sure if ddog did any of these mods before his SC:
evoms intake
header
mufflers
giac flash
lwf
for my style of driving (wringing the engine out up high in the tach) it was worth it. for others, it might be disappointing becasue all the gains are high in the rpm range... still noticeable for regular street driving though. it was totally worth it on the track too.
dynapac runs showed a best run of 277rwhp. that's about 318 HP with 13% driveline power loss.
if you are expecting a large push from these mods don't bother and get a supercharger or TT.
if i were to do it again, i would do it in a heartbeat... i would've also added sport cats though
evoms intake
header
mufflers
giac flash
lwf
for my style of driving (wringing the engine out up high in the tach) it was worth it. for others, it might be disappointing becasue all the gains are high in the rpm range... still noticeable for regular street driving though. it was totally worth it on the track too.
dynapac runs showed a best run of 277rwhp. that's about 318 HP with 13% driveline power loss.
if you are expecting a large push from these mods don't bother and get a supercharger or TT.
if i were to do it again, i would do it in a heartbeat... i would've also added sport cats though
