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Looking for some advice on a muffler. Replaced the exhaust from the turbo back and feels like I lost some power now that there is no back pressure. Running a 4" exhaust on an 06 5.9 cummins
Exhaust
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Ok, please educate me. What is drone
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Drone is a loud low frequency sound that reverberates through the truck at certain RPM's. You can feel drone and much as you can hear it.. It seems to match the frequency of the truck body. It's usually worse at certain RPM's and when lugging up a hill. It will give you a headache and make you feel like your ears are bleeding on a long drive. Most of these tucks will drone like crazy without a cat and a good muffler in place. An FTE or Flo Pro twister does a good job of dampening it without building much restriction / back pressure in the exhaust system.
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Thank you for the education. Last question. Will that make it feel like inlist power? I feel like when I put the exhaust on all the way back that I lost power and the pedal feels dead
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Charged engines need the exhaust to be as free flowing as possible. No backpressure... So unless you did something different besides change the exhaust system, whatever you think you feel is only in your mind. :thumbup:
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From the turbo back
Look at the turbo clamps .
Most likely leak at that point . No boost?
Sent from my SAMSUNG-SM-T217A using Tapatalk
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No, I've got boost. Just a dead pedal
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What's the diameter of the stock exhaust pipe?
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No, thats a misnomer. If anything, a more free flowing exhaust on a turbo charged engine will increase bottom end as spooling will take place sooner. Although changing the turbo can definitely alter the power curve but we're talking stock components here.
I believe the factory 3rd gen 5.9 was still 3". Although the OEM exhaust uses crimp bending which reduces the bent sections down to around 2.5" or less.
I included a picture for reference.
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When I replaced the 4 inch factory exhaust on my 05 with an aftermarket 4 inch free-flowing system, my turbo definitely spooled quicker and I had a noticeable "seat of the pants" increase in power. It was especially noticeable when I rolled into the throttle at around 35 mph. The turbo kicked in instantly and accelerated hard enough that it pushed me back in the seat. It also cleared up some of the smoke I was experiencing on the higher settings of my Smarty JR. I'm also running an S&B Cold air intake. The combination of the intake, exhaust and Smarty Jr. made a big difference in HP and torque. EGT's dropped a bit too. The exhaust was the last piece added and had an unexpected dramatic impact in turbo performance. I'm guessing my OEM exhaust system was partly plugged up. I did experience a loss in fuel mileage for awhile though, because I couldn't keep my foot off the skinny pedal. I was too much fun!
It was too loud though and the drone was awful - even with an expensive Hushpower muffler. A 17 inch FTE resonator helped out a lot and didn't seem to add any significant restriction to the exhaust. I would put in a 30 inch if I could get it to fit. If you're experiencing a power loss, I would suspect something else - namely a boost leak somewhere. If you still have your old exhaust components laying around, you could reinstall your muffle and cat (if you had one) and try it.
It was too loud though and the drone was awful - even with an expensive Hushpower muffler. A 17 inch FTE resonator helped out a lot and didn't seem to add any significant restriction to the exhaust. I would put in a 30 inch if I could get it to fit. If you're experiencing a power loss, I would suspect something else - namely a boost leak somewhere. If you still have your old exhaust components laying around, you could reinstall your muffle and cat (if you had one) and try it.
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2003 and early 2004 had a 3.5 inch and starting with the 2004.5 it was a 4 inch.
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Thank you. :thumbup:
Although I dont think any OEM exhaust is mandrel bent but still use the crimp bending. Terrible way to bend the tubing...
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