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Do I need to tune my car or get any bad readings if I remove muffler?
Only things you will need are a set of good ear plugs and def neighbours so they don't call the police and complain!......lol [;)]






No there is no tune required for a muffler delete!
 

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Meh.
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I don't know if a tune will fix this or not, but I do know you'll lose power without an exhaust. I cant give you the specific of why, but your engine is build to run best with the back pressure that is created through your exhaust. I know because I ripped my flex pipe in two once and the car was a dog until I got it fixed.
 

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I don't know if a tune will fix this or not, but I do know you'll lose power without an exhaust. I cant give you the specific of why, but your engine is build to run best with the back pressure that is created through your exhaust. I know because I ripped my flex pipe in two once and the car was a dog until I got it fixed.
Removing the muffler will not effect the precious back pressure.....lol.

Should google exhaust back pressure and find out what it is and how it works!
 

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It's about exhaust scavenging, not back pressure. A 2 stroke uses reflected exhaust pulses (pressure) to stuff fuel back in.
 

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Meh.
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Removing the muffler will not effect the precious back pressure.....lol.

Should google exhaust back pressure and find out what it is and how it works!
Um yeah? Back pressure in the exhaust system is created through the converter, muffler, bends in the pipe, and any other obstructions. remove any of these obstructions and your changing your back pressure and the performance of your engine. Now I'm just passing on information on read/heard but guys who have done this can gain horse power but lose in torque which will make the car feel groggy at lower RPMs. You wont know how much of an effect the lose of a muffle in the system will have till you try it but there would be an effect.
 

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The term back pressure is always misused in the context of exhaust!

Back pressure is nether wanted nor required to help an engine perform. It is exactly the opposite. Have you ever seen a 6500hp Top Fuel Dragster with mufflers? According to your theory these engines would have more power if they had long exhaust systems with back pressure in them. But they don't! Same goes for F1 engines.

When you crack your exhaust or put a hole up close to the engine it's not the reduction of back pressure that causes the change in performance. It is the change in how the pressure waves act inside the system. The power is still there, it will usually be in a different area of the RPM range. Usually up higher!

Here is a spot on explanation of back pressure and exhaust scavenging, I didn't want to have to go into my fluid dynamic books and regurgitate, so I Googled it!; http://www.dsmtuners.com/threads/exhaust-the-straight-scoop-on-backpressure.168578/
 
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Do I need to tune my car or get any bad readings if I remove muffler?
Why would you want to do that for? If you want to change out the tone, get another muffler.
 

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Discussion Starter · #9 ·
Well what mufflers fit the damn area is so small. I got a thrush glass pack and took it back it was too long to fit in the area where the current muffler is (near the rear wheel well). I have flex pipe now where my lunchbox was. So what should I do for more sound ?
 

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Discussion Starter · #10 ·
Glass pack or thrush welded if I get the thrush welded I now see if have to get more flex pipe and cut more exhaust out to make it fit I want the old muffler gone its stock and I don't trust it does anything performance or sound wise for the car
 

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Meh.
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The term back pressure is always misused in the context of exhaust!

Back pressure is nether wanted nor required to help an engine perform. It is exactly the opposite. Have you ever seen a 6500hp Top Fuel Dragster with mufflers? According to your theory these engines would have more power if they had long exhaust systems with back pressure in them. But they don't! Same goes for F1 engines.

When you crack your exhaust or put a hole up close to the engine it's not the reduction of back pressure that causes the change in performance. It is the change in how the pressure waves act inside the system. The power is still there, it will usually be in a different area of the RPM range. Usually up higher!

Here is a spot on explanation of back pressure and exhaust scavenging, I didn't want to have to go into my fluid dynamic books and regurgitate, so I Googled it!; http://www.dsmtuners.com/threads/exhaust-the-straight-scoop-on-backpressure.168578/
OK. I'll give you the specific terminology and technology behind some of this stuff but the simple fact remains that the OEM tune was done using an OEM exhaust so changes to that will effect performance (maybe not alot consider the small change that is made) unless some retuning to counter. I've never heard of a Top Fuel Dragcar or an F1 car that hasn't been properly tuned for every change that is made to it's engine so that argument is null.

Now I have no intention of cluttering up the OP's thread anymore with this back and forth so this will be my last reply. Take the info I have given however you like but I stand behind my statement that a cars performance will be hurt in some ways if the muffler is removed without any further modifications.
 

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Hey guys I just removed the muffler on my 2010 5 spd and I'm very happy with it. I haven't noticed any significant lags at all and it's not too terribly loud. I think it sounds pretty good, a lot better than I was expecting. It might not be for everyone but I like it.
 
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