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Old 08-02-2003, 02:04 PM   #11
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I just finished my exhuast yesterday. I have no resonator (never had one) a hi-flow cat, a Magnaflow F-body muffler, and the stock 2.5" diameter pipe. It sounds awesome, but gets a little rappy for a second after dropping the throttle sometimes. With a stock cat, it won't do this. Anyone wanna hear it?
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Old 08-02-2003, 02:10 PM   #12
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Bring it..chances are its very similar to mine
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Old 08-02-2003, 02:10 PM   #13
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Quote:
Originally Posted by willwren
I just finished my exhuast yesterday. I have no resonator (never had one) a hi-flow cat, a Magnaflow F-body muffler, and the stock 2.5" diameter pipe. It sounds awesome, but gets a little rappy for a second after dropping the throttle sometimes. With a stock cat, it won't do this. Anyone wanna hear it?
Most of you know already that I had the Cat done about 6 months ago when it turned into a giant baby rattle. Well, apparently it puked it'* guts out bad enough to launch shrapnel through the muffler. I've been running more restricted than stock exhaust ever since. I've never really been able to 'feel' my new performance cat until now. This muffler reall woke the beast up. At idle, you can't tell what I've got, which is what I wanted (I know the Flowmaster'* are obvious at idle, but the Dynomax and Magnaflow are not). When I blip the throttle, it really rumbles. I get no resonation in the cockpit, either.

BTW, my 'video runs' the other night are what kinda did my stock muffler in, I think. Sounds like a baffle let go in there, and I could actually feel it through the gas pedal. I got my Magnaflow installed for cheaper than a stock muffler would have been.

After the Stock mufller was cut out, I laid the two mufllers side by side for comparison. The passages through the stock muffler are SMALLER than 2.25", where the Magnaflow is 2.5"+ all the way through. This accounts for alot more volume, and way less restriction.

What this means is that those of us with a 2.5" stock pipe diameter are necking down to 2.25" or less in the Cat AND the Muffler stock. I'm pure 2.5"+ all the way out now.
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Old 08-02-2003, 02:49 PM   #14
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Will,

On my '92 ssei, the cat has also turned into a baby rattle. Did you have your new cat welded right up to all the other stock pipes? And which cat did you use?

Do you have any more detail on exactly what muffler that is?

Thanks,
Steve
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Old 08-02-2003, 03:00 PM   #15
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Just weld your Cat (Hi-flow) right to the stock location. I used an Autosound with larger inlet/outlet, then necked down to fit the stock pipe. No chance for restriction. It was 125 (us$) installed, about 6 months ago.

The muffler is designed for an easy replacment in an F-body (camaro/firebird). With a V-8. Magnaflow'* part number is ****. Don't have it written down, but I can get it. The Camaro/Firebird muffler has an inlet and outlet on one end, and another outlet on the other end, just like the SSE/SSEi needs. HOWEVER......to make this easier, buy the one with the 2.25" inlets and outlets. This is because the tips are 2.25". Just flare the INLET back out to 2.5" to meet the stock inlet pipe size. No worries, the chambers inside are still 2.5" plus, so you don't loose anything. Just keeps you from having to neck DOWN 2 outlets.
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Old 08-02-2003, 03:11 PM   #16
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For you 87-91 single outlet people like me, the set up and end resultant sound is a bit different. SSE/i have dual outlets so I'm interested in hearing the difference between Bills Magnaflow/high flow cat, to my Magnaflow/High flow cat.

And ya, Magnaflow P/N is a pain, i can't find it. However, ask them what car you have and they'll get you the correct muffler.

I also think (not cannot confirm) that the exhaust tip will affect the quality of the sound and rumble. Any loose vibrations may cause more of a tinny or rattling sound. I'm no sound engineer, thats just my logic talking
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Old 08-02-2003, 03:16 PM   #17
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Text of an offline conversation between Jim and I....might be food for thought:

Quote:
wrens67: Get in there and tell more about your magnaflow, bitch.
jim_wallace0: my influence was not strong enough
jim_wallace0: I tried..no one really cared..lol
wrens67: You ever get audio of it? More 87-91'* are interested. Mine is totally different with the dual outlet setup.
jim_wallace0: sure..I posted it 2 times
wrens67: http://www.bonnevilleclub.com/forum/...?p=66728#66728
wrens67: You remember the links? I'd like to hear yours again.
jim_wallace0: I'll go grab it for you
jim_wallace0: its also posted on my CD.com page
jim_wallace0: http://jonathaneger.com/rumbly.wav
jim_wallace0: it cuts out for some reason...play it 2 times
jim_wallace0: 1st half in back of the car outside..then 2nd half is inside the car
wrens67: Hard to tell. Sounds like your recorder had auto level control on the input to the mic. Do you get any rapping after letting off a throttle blip?
jim_wallace0: not really...no rattle in N or P between 1000-3500 but i never rev that high, in gear..no rattle at all. Somehow I think the tip helps to reduce vibration giving a purer sound
jim_wallace0: you can hear the igntion fire up right?
jim_wallace0: at the beginning..the vibration of the air against the cams mike causes the cut offs
wrens67: Tips might be it. My exhaust guy said if I'd stayed stock on the cat, or added a resonator, there would be no rap, but I'm not into adding backpressure Kinda trying to get rid of it. Your tips may be acting as resonators. I might have to consider that later.
jim_wallace0: maybe so. I have heard bonnie94sse new exhaust..even tho it is Maganflow it sound NO WHERE near mine..he needs to go high flow cat and loose the res.
jim_wallace0: I suspect his SSE will sound exactly like yours once he upgrades the cat and loses the res
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Old 08-02-2003, 03:23 PM   #18
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Default hmm...

If your "emmisions" testing is just visual then punch your cat
If you dont have any emmisions RUN STRIGHT PIPES(accually this would hurt peformace on these little 3.8s)
If you have real emmisions testing your going to have to buy a high flow cat:(
-I have stright pipes on my 69 c/10
-flowmaster mufflers on my 01 camaro (no cats)
-soon to be flowmaster or dynomax muffer on my 92 trofeo (no cat)
-stock cat/muffer on my 87 toronado
-Anyone know a good muffler to put on my DURAMAX?... lol dont really matter damn trucks govered from the factory at 155km/h. Lots of pick up already even with the welder.
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Old 08-02-2003, 03:26 PM   #19
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I strongly suggest a catalytic converter. High flow is worth the money, you stay legal anywhere, you maintain a sense of environmental responsiblity and you get the HP gains.

Any questions?
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Old 08-02-2003, 03:37 PM   #20
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I agree with the cat. The right cat will be invisible to your car as far as backpressure is concerned. It may also help reduce the 'rappy' sound in some setups.

Here'* the clips I just shot. Pretty good audio:

http://home.comcast.net/~bonnevilleclub/start_idle.MPG
(cold start and idle)

http://home.comcast.net/~bonnevilleclub/warm_idle.MPG
(shot from the rear, and walking around the car)

http://home.comcast.net/~bonnevilleclub/footwork.MPG
(the GOOD stuff)
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