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Cat Bypass installed - First Impressions

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Old 06-03-2011, 03:45 PM
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mike9186
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Default Cat Bypass installed - First Impressions

I just installed a Cat Bypass that I bought in the classifieds section of this site. I think it is a fairly well made piece as it has circular baffles around the inside of the bypass and the welds are supersmooth. I already have a Steve Wong chip installed. First impressions are positive.

1. Better throttle response
2. Better sound (throaty) and not too loud
3. Easier to get rolling from a standstill
4. Maybe more power but not really sure

There a faint smell of fuel in the cabin at start up but nothing overwhelming.

When I looking inside the original cat and move it around I can see the light shift a bit. I assume this is a sign of clogging (and why I am noticing such an improvement in performance with the bypass). So I am wondering if there is a way to clean the inside of the cat while it is off the car? Can I soak it in something? Spray something inside to clean it out? I won't try anything until I hear if it is possible or not.
Old 06-03-2011, 04:18 PM
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Silvertarga
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My fabspeed cat bypassmade the noise more tolerable (of course it was replacing a 21 year old cat that had seen better days) Absolutely no issues with heat either..

I heard that you can flush the cat with Acetone or MEK...never tried it
Old 06-03-2011, 04:49 PM
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philchil
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Do you have a primary or secondary by-pass too?

Heard it gets pretty load if you have more than one by pass.
Old 06-03-2011, 05:13 PM
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Silvertarga
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I am running the Fabspeed Dual Outlet Maxflo Exhaust, upon adding the Fabspeed bypass the exhaust became quieter and deeper...a perfect combo

The Fabspeed is pretty loud when using both outlets, I have heard that I can baffle one of them just dont know what I would use to do that,

When i drive by the cops look for a Harley :-)
Old 06-03-2011, 10:12 PM
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mike9186
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I have a primary bypass as well. I ran the car for a friend and he agreed that the sound was not too loud.

I think I really lucked out with the quality of bypass I bought.
Old 06-03-2011, 10:15 PM
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christallon
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Same set-up that I run. Glorious sound in a tunnel I do smell semi-burned fuel at times which reminds me of the early car experience.

Enjoy the new set-up!!!
Old 06-03-2011, 10:15 PM
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SuperUser
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Originally Posted by mike9186
I have a primary bypass as well. I ran the car for a friend and he agreed that the sound was not too loud.

I think I really lucked out with the quality of bypass I bought.
You got a great deal, I just missed it..
Old 06-03-2011, 10:47 PM
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philchil
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Mike...sounds good...I just got a primary by pass...definitely like the sound better than stock...sounds more like a porsche in my mind...throaty especially during warmup, then it mellows a little bit. I'm considering a 200 cell cat to get just a tad more sound when accelerating, but I don't want to sacrifice sound quality at cruising speeds (got a high end stereo system). Also concerned with loss of torque due to lack of back pressure...have you noticed any changed below 4k rpm? Btw...in getting the 91 octane Wong chip next week!
Old 06-04-2011, 12:32 AM
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mike9186
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Hi Phil,

I'm feeling no loss of torque at low revs at all. Like I mentioned I'm having an easier tie getting the car going from a standing start. I do not know if it's the result of the bypass or from removing the dirty clogged old cat.
Old 06-04-2011, 09:09 AM
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philchil
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Good to hear on the torque ... Sounds like that concept may be overplayed...

I'm looking forward to my chip install...my rsa pulls strong...I am hopeful that I feel the same results as others that have gotten the Wong chip....I'll post my impressions when I get it....thx!
Old 06-04-2011, 09:16 AM
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swmic

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Same setup I had on my 964 and loved it! Sounds way better than my 993.
Old 06-04-2011, 10:31 AM
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Laker
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Originally Posted by philchil
.... I'm considering a 200 cell cat to get just a tad more sound when accelerating, but I don't want to sacrifice sound quality at cruising speeds (got a high end stereo system). ...

Unless you are lucky enough to be able to cruise at WOT, you won't notice a big increase in sound in the cabin unless you go under a bridge/tunnel. Or perhaps I've just gotten used to it and subconsciously tune it out. I have cat bypass, Cup pipe and a Wong 93 octane chip. Since the car is built to do 160, cruising at 80 is not that loud in the cabin, until you punch it. I have crappy audio (goes to 4 on the Spinal Tap scale of 11 before distorting), and it is by no means drowned out.
Old 06-04-2011, 10:56 AM
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+1
I want one...
Old 06-04-2011, 02:50 PM
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philchil
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Thx laker...what does WOT mean?
Old 06-04-2011, 02:59 PM
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ThomasC2
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Wide open throttle...

Thomas


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