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Is 2.5" too small?

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Old 01-06-2009, 10:09 AM
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Default Is 2.5" too small?

I was told by my muffler guy that I would not need 3" exhaust, and that anyone that asked for 3" didn't know what they were talking about. So I ordered a 5"x8"x18" 2.5" magnaflow and 2.5" cutout. I will only be running one pipe btw. So is this too small or should I find a 3". Summit and Jegs are out of the 3" of the same size...
Old 01-06-2009, 10:29 AM
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3'' exhaust is good for the track but as for everyday driving and use I'd go with 2.5''. I went with 3'' mufflers and 2.5'' tubing. But as far as running one pipe I'm not too sure. I think 3'' would be a good idea in that case but wait and see what everyone else thinks.
Old 01-06-2009, 10:29 AM
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tell your muffler guy that my truck comes from the factory with 3" pipes, but maybe the general didn't know what he was talking about...
Old 01-06-2009, 10:39 AM
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For a single exhaust a 3" is about what is needed for a mild N/A setup. Your exhaust guy doesn't know how to make any real power. I run into those dumba**'s all the time. Stock 5.3L exhaust is 2 3/4" and that is for a completely stock truck. Why go smaller?
Old 01-06-2009, 10:56 AM
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Single exhaust? I wouldn't go with anything smaller then 3 inch. Duals? No smaller then 2 1/2 but thats just me. If I were to run a single exhaust on my 95 it would be a 4 inch pipe mostly because I can and because I hate back pressure.
Old 01-06-2009, 11:09 AM
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Aight, damn. Anyone know where to get a 5"x8"x18" 3" muffler since summit and jegs are out of stock for the next month?
Old 01-06-2009, 11:13 AM
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I think that 18" is going to be too quiet for you IMO

I'm running the 3" in, 2.5" dual out with turndowns and I've got a cam, longtubes, and no cats and I think its pretty quiet sounding. You can just about hear my exhaust leaks over the whole exhaust haha (I'm gonna get V-bands soon)

What kind of sound are you wanting? Is he just welding up a muffler in the stock location with stock piping? If he's using stock piping you will need a 3" muffler, otherwise you're just restricting flow even more.
Old 01-06-2009, 11:15 AM
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Here is one that is in stock, but it is the 14" case and will be louder
http://store.summitracing.com/partde...5&autoview=sku

Heres another one that is 5x8 and is 14"
http://store.summitracing.com/partde...5&autoview=sku

Here is an 18" but is 4x9
http://store.summitracing.com/partde...5&autoview=sku
Old 01-06-2009, 11:18 AM
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I would run a single 3" if I were you. 2.5" is smaller then factory, especially if he is not capable of making madrel (sp?) bends. Granted I am moving allot more air but I have dual 3" with a X pipe and didnt notice any loss of lowend. Check some of your local shops, allot of shops carry Magnaflow mufflers and I cant imagine 3" being that hard to find. JMO
Old 01-06-2009, 11:22 AM
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Originally Posted by 03sierraslt
I would run a single 3" if I were you. 2.5" is smaller then factory, especially if he is not capable of making madrel (sp?) bends. Granted I am moving allot more air but I have dual 3" with a X pipe and didnt notice any loss of lowend. Check some of your local shops, allot of shops carry Magnaflow mufflers and I cant imagine 3" being that hard to find. JMO
lol of course you're not going to lose any low end with a boosted 6.0...

I'd sure hope not anyways


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