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Discussion Starter #1
Well I Bought A Cut-Out From My Friend And well Im A Noob When It Comes To These Things, So i Was Wondering if Should Get It Done. I Have A 01 Silverado With A Single Chamber Cherry Bomb Muffler And I Got The Y-Pipe Set Up. If I Get The Cut-Out Done Will I Loose The Way The Muffler Sounds With It Open?
 

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If you put a cutout in the exhaust system it dumps the exhaust at the cut out, you will have open exhaust in other words. No muffler, no tail pipe no nothing beyond the cut out.

Also not sure about the legality in your state. You don’t mention it.

Exhaust cut outs are made for racers who want unrestricted exhaust for racing.
 

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The legality of it is my concern too. I had glass packs on my '62 so I didn't worry about it too much, loved that sound. :)
 

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Exhaust cut-outs serve a purpose for vehicles driven on the track, but on a street driven vehicle it's useless unless your trying to attract attention, which will usually be the wrong kind.

Most modern internal combustion engines require some backpressure in the exhaust (actually they require scavenging of the cylinders during the exhaust stroke which is a product of backpressure). By using an exhaust cut-out your reducing the backpressure thus reducing the engines scavenging abillity and making it less efficient (horsepower and mpg). The cylinder will retain some of the burnt gasses and not get a full clean fill on the intake stroke. At high rpms the engine managing system will only allow the engine to go to a set max rpm, so you'll gain very little if nothing there.

Yes race vehicles use open exhausts, ever seen one take off at anything less than warp speed and max RPM's? They dont, without backpressure they have verry little low end tourque. The engines are built to run max rpms most of their short lives, at these rpms they dont require as much exhaust scavenging to clean the burnt gasses out of the cylinders because of the high flow it's forced out.

Are modern exhaust systems perfect then? No they can be made better with a combination of steel tube headers, mandrel bent pipes, free flowing cat convertors, and free flow mufflers. The combination has to be just right, all these items on one vehicle may actually slow it down. Lots of factors have to be taken into account, axle ratio, rear wheel horsepower, and even the vehicle engine sensors have a role in things.

So unless you just want to make your truck obnoxiously loud to annoy people you should probably look at other methods to achieve more top end. Depending on where you mount the cut-out this method may cause more problems than it's worth.
 

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Just for future referrence. On a vehicle like this, if you plan on taking it to the 1/4 or 1/8 mile drag track. There is an exhaust cut off point. Low restriction as opposed to no restriction can change your times dramatically. My 350 in my 84 1/2 ton actually ran faster with exhaust on (just muffler and tail pipe) then with it unbolted off to the side. I experimented with this a bit during one day at track. The noise when undone was unbearable in the truck cab too. It actually ran almost a full second and a half slower. At a 1/4 mile 112 mile an hour pass I thought my head was going to explode during run out. (Cuz the windows have to be up, track rules)
So in short you've made a good decision, its annoying and will gain you nothing except an SES light on dash, and a throbbing need for aspirin...IMO
 

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Discussion Starter #10
So where exactly would you put them? because all i wanted to do is make my truck louder and i was told cut-outs where the cheapest way to make it louder. plus i'm not planning on doing the track thing i just want to drive around on a loud truck :smile:
 

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Did you already buy it?
I'm seeing cut outs priced around $50.00, and then you have the legality issue.
But you could pick up glass pack mufflers for a little over $20.00. Might have same legality issue tho.

Oh, never mind, I see you said you already bought it.

You probably have dual cats on your truck, so anywhere after the y pipe and before the muffler should be fine. If you get a controller, you can adjust the amount of opening, so you can get your louder tone, and not lose any power no matter where you place it.

Keep us posted on what you end up doing.:great:
 

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Discussion Starter #12
Well i got the cut-outs for 30 but they're not the electrical type. and i do have dual cats with the y-pipe i might end up doing it but im not so sure. but i will let you guys know what i end up doing. but thanks for your advice.:smile:
 
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