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Old 09-27-2009, 08:38 PM   #1
KrazyAz
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New exhaust...too poppy sounding

Hi 2 all.hopefully someone will have an answer to my problem.I just installed a set of custom built headers. 1.75" 16g tubing and new 2.5" 16g tubing with delta 40 flowmaster mufflers.The exhaust dumps out the sides behind the back wheels on my longbed.At idle it sounds great.Accellerating it begins sounding very poppy like glass packs.The old exhaust with same flowies sound throaty from idle to top speed.Old exhaust exited the rear of truck and was almost straight tube all the way back.The new exhaust has a u bend over axle then a 90 to exit the sides of the truck.Are the bends causing the poppyness?If not then what might it be?thank you in advance for your help.

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Old 09-27-2009, 08:56 PM   #2
Mike C
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Re: New exhaust...too poppy sounding

My buddies Chevelle sounded like it had glasspacks on it as well. We have the same mufflers, and my Camaro sounds great. The difference? A balance pipe. I'd zip back to the muffler shop and have them fix you up if you don't have one.

Another thing to consider is the new exhaust change your jetting requirements. Backfiring in the exhaust is a sign of an over-rich situation.

Other than that, don't know what it could be.
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Old 09-27-2009, 10:14 PM   #3
BLUE THUNDER
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Re: New exhaust...too poppy sounding

Yup, you need a balance tube. It will sound a lot better.
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Old 09-28-2009, 06:34 AM   #4
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Re: New exhaust...too poppy sounding

X-3 cross over pipe will help a lot.
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Old 09-28-2009, 07:59 AM   #5
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Re: New exhaust...too poppy sounding

also check for leaks.....I know but if here is a leak somewhere it will do it alittle too when we where kids it was the thing to do if you wanted to make it backfire drill a little hole near the header.....what where we thinking??
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Old 09-28-2009, 07:39 PM   #6
KrazyAz
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Re: New exhaust...too poppy sounding

Thank you for the responses.I will check all suggestions out.Just relized that I posted in the wrong section.....dam newbie..lol
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Old 09-29-2009, 02:45 PM   #7
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Re: New exhaust...too poppy sounding

Are the ends of the pipe straight or cut at an angle? Years ago someone told me that when the tips are cut off at a 45 degree angle, the exhaust sounds better. So I cut off the tips of the exhaust on one of my vehicles. If you held the cut off piece back up to the pipe, and then took it away, it sounded different. Best way to describe it...when the ends are straight it sounds more "poppy". I would tape some angled pieces on your exhaust and see what kind of a difference it makes.
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