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Old Jun 23, 2004 | 05:16 PM
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Ok, I HAVE used the search button on this, but still have a few questions.
Are the only two versions of this the Flowtech manual cutoutsand the Quick Time Performance electric ones?

I can't find the website selling the Flowtech ones so could someone link me there, and do they only sell manual ones?

What are everyones recommendations on doing this, I'd REALLY like to just have an electric version, because I'd like to easily switch between them, but the price on QTP's website seem steep. Has anyone found a cheaper way to get an electric version of the cutouts?

Also I assume I need two of these things, but I'm not really sure about that. I have the SLP dual-dual exhaust if that means anything. Does it depend on where I put the cut-out if I'd need two of them.

Can you buy the actual cutouts from somewhere, and then just get the electric switch part of it from QTP, and is that a cheaper alternative than just getting all from QTP?
Thanks for everyones help with this.
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Old Jun 23, 2004 | 05:20 PM
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Try this site out: LS1 Speed
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Old Jun 23, 2004 | 05:26 PM
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You only need one so long as you have an I-pipe.

You might also consider the new Street Pro electric cuttout. It's not cheap but it is ceramic coated and SWEET! No worries of leaks, rattles, screws rattling loose, or failures so I hear. Having your electric cuttout fail to close in the middle of traffic is annoying and can really draw attention from "The Man" too.

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Old Jun 23, 2004 | 05:39 PM
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Those look nicer, but that is $245 for only one of them correct.

And if I only need one cut-out for my car, then why do some people have two on theirs? And if my car is completely stock I'm assuming I have an I-pipe?
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Old Jun 23, 2004 | 05:49 PM
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Yes, you have an I-pipe.

Because they want two for a bit of added volume (trust me, one is still LOUD) or they have the mentality that two is surely better than one. There is no performance gain simply from having two cuttouts rather than one. In either case your exhaust system will no longer be a restriction. I run one 3" cuttout in the '02 listed in my sig. I ran one cuttout in my '00 as well when it was running low 10s in the 1/4.

However, if you're running headers and big power you should be careful to run a Y-pipe of adequate size. A 3" into a 3.5-4" collector with a 3" cuttout will work perfectly in this case.
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Old Jun 23, 2004 | 06:16 PM
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So in other words I would weld the cutout into the section of my exhaust where it is running together? But that is section is larger than the rest of it so what size would I need?
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Old Jun 23, 2004 | 06:26 PM
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Originally Posted by Colonel
Yes, you have an I-pipe.

Because they want two for a bit of added volume (trust me, one is still LOUD) or they have the mentality that two is surely better than one. There is no performance gain simply from having two cuttouts rather than one. In either case your exhaust system will no longer be a restriction. I run one 3" cuttout in the '02 listed in my sig. I ran one cuttout in my '00 as well when it was running low 10s in the 1/4.

However, if you're running headers and big power you should be careful to run a Y-pipe of adequate size. A 3" into a 3.5-4" collector with a 3" cuttout will work perfectly in this case.
by any chance, did u make a video then have it put into LS1sounds.com ???
Coulda swore i seen a video and it says 422 with cut-out, '00 Z. Are u the big guy in the car? Looked like my sisters boyfriend .



Anyways, can u actually loose power from opening the cut-out since there will be virtually NO back pressure in the exhuast?
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Old Jun 23, 2004 | 06:53 PM
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It is possible to lose some lowend with dual cuttouts. Not so much an issue with a single cuttout. But how important is the power below 4000 during a drag race? Not very.

Nope, wasn't me in that video so far as I know. I'm not a big guy. 172 lbs now and the most I've ever weighed was 188.
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Old Jun 23, 2004 | 06:55 PM
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"So in other words I would weld the cutout into the section of my exhaust where it is running together? But that is section is larger than the rest of it so what size would I need?

The stock I-pipe is like 2.75" I think. Get a 3" cuttout.
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Old Jun 23, 2004 | 07:00 PM
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Are there any problems as far as electric cutouts or would it be better and more reliable to have it manually like reach under the car and flip the butterfly open. To me this wouldnt be a problem to do. But would u go electric or just manually open the valve to open the cut out "Release The Power!!!" . Have u ever seen a non electronic cut-out before on a modern (LS1) car?
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Old Jun 23, 2004 | 07:22 PM
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This statement of mine from above kinda sums it up.

"No worries of leaks, rattles, screws rattling loose, or failures so I hear."

This is why I now recommend the Street Pro for those who can swing it.

I have never seen a manual butterfly cuttout. Only conventional (three wing nuts and a plate) and electric. The Street Pro is of an entirely different design than other electric cuttouts.
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Old Jun 23, 2004 | 07:22 PM
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The two most often used here are QTP and McCord.
Electrics can have problems, like loss of sealing, loss
of small parts, etc. It seems earlier models were
"learning experiences" and the reliability has gotten
a lot better.

If you're into diesels, maybe you know about the
exact opposite of the cutout, which is the exhaust
brake. For diesels you normally leave it open but
can close it. These are better built (all-steel, for
the heat) and much more expensive.

Basically they are all just 2.5" or 3" butterfly valves.
You could probably get a 3" steel butterfly valve
off eBay if you waited long enough, and work it
with a lever like Fred Flintstone. But Jetsons
have it easier. Until stuff breaks.
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Old Jun 23, 2004 | 08:15 PM
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Ok, now just a question about WHY it works. I understand obviously that when the valve in the cutout is closed then the exhaust gases will flow through normally. Then you open the valve, but what makes the exhaust gas flow out that shorter path then. I originally thought that the opened valve then went to the othernormal exhaust route and shut it off, but that's not it. So why does opening the valve make the exhaust want to go that way, just because it'll be easier for it too? But why, from a technical standpoint.
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Old Jun 23, 2004 | 09:13 PM
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Originally Posted by Ru2n00n3er
Ok, now just a question about WHY it works. I understand obviously that when the valve in the cutout is closed then the exhaust gases will flow through normally. Then you open the valve, but what makes the exhaust gas flow out that shorter path then. I originally thought that the opened valve then went to the othernormal exhaust route and shut it off, but that's not it. So why does opening the valve make the exhaust want to go that way, just because it'll be easier for it too? But why, from a technical standpoint.
Your exhaust will create back pressure, when you open the cutout the gases will follow the path of least resistance.
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Old Jun 23, 2004 | 09:21 PM
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i know i have a summit mag laying around here somewhere
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Old Jun 23, 2004 | 09:27 PM
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as for loudness, my car (macs, OFY, and corsa) is louder than a stock exhaust system with a cutout.
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Old Jun 23, 2004 | 09:28 PM
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jaberwaki, the guy in ur sig looks like some kind of gay **** star. makes me feel uncomfortable
jk.....but that guy really does look some gay **** star. Not that ive ever seen one but he just looks like a ***.


Would the cut-out allow more horsepower if it were placed right where the headers meet as opposed to being right before the rear end/right before the muffler.
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Old Jun 23, 2004 | 09:32 PM
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lmmfao........hahahahahahahaaaaaa..... you got me ... thats funny as hell...
thanks i now have soda all over the screen.....hahahahahaaaa...

the pic is of ALEX... from "A Clockwork Orange" he's not a ***.... but you have everyright to feel uncomfortable with him looking at you

if you haven't seen the movie , its a cult classic... everyone should see it at some point...
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Old Jun 23, 2004 | 09:34 PM
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Originally Posted by 1999Z28
as for loudness, my car (macs, OFY, and corsa) is louder than a stock exhaust system with a cutout.
Oh my God, how could that be and how do you live with it? Damn dude I can barely hear myself think over our cutout...
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Old Jun 23, 2004 | 10:02 PM
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Originally Posted by jaberwaki
if you haven't seen the movie , its a cult classic... everyone should see it at some point...
Got Milk?
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