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Old Aug 29, 2015 | 11:36 AM
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Default Back Pressure Question

I've heard a lot of mix reviews on this. When I got my short shots, the stock baffles are wide open. It seemed as though I lost some power, and they were a little too loud for my liking on the highway and my stealership buddy told me that if I put the quite baffles in, I would get some power back. I did so and it seems about the same, maybe a little better. But I cant tell if maybe it's in my head. Anyone ever dyno a baffled exhaust system vs a wide open drag style pipe? Thanks in advance
 
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Old Aug 29, 2015 | 12:23 PM
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Thought maybe this would help

 
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Old Aug 29, 2015 | 12:38 PM
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Without tuning, you're going to lose torque with straight pipes.
 
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Old Aug 29, 2015 | 12:46 PM
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Originally Posted by NORTY FLATZ
Without tuning, you're going to lose torque with straight pipes.
Tuning or not, you will lose torque with straight through pipes. Particularly low & mid end torque.

But, it would be cool to see the dyno curves for a bike only changing out the pipes.

Btw...the above S&S video is pretty cool.
 

Last edited by TriGeezer; Aug 29, 2015 at 12:51 PM.
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Old Aug 29, 2015 | 01:09 PM
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Yes. I have short shots, quiet baffles, and a fuelpak set up for them. While I'm not making tons of power compared to most here, my tourqe curve is nice and flat. No dip, pulls great from down low and stays there. I'll dig up the sheet and post it up.
 
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Old Aug 29, 2015 | 01:24 PM
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Originally Posted by TriGeezer
Tuning or not, you will lose torque with straight through pipes. Particularly low & mid end torque.
100% TRUE

But, it would be cool to see the dyno curves for a bike only changing out the pipes.

Btw...the above S&S video is pretty cool.
Nice pic of South Carlsbad!
 
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Old Aug 29, 2015 | 02:28 PM
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Here is my dyno sheet. Shortshots, quiet baffle, fuelpak, stock AC (for a bit longer). I'm very pleased with the torque curve. It's kind of had to see the line, but it's there, hitting 80 lb-ft at about 2300 rpms - ad staying there until about 4000 rpms.


 
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