New Exhaust, Less Performance?
Seasoned HDF Member
Joined: Jul 2007
Posts: 6,336
Likes: 67
From: SW Minnesota
OP: DO NOT EVER DO THIS. (And he focked up a set of Rineharts with this foolishness.)
You can try a different baffle (quiet baffles, for example) or even a different tune.
You built a high performance motor so what did you expect.....Cadillac quiet? Won't ever happen without losing a bunch of power.
You can try a different baffle (quiet baffles, for example) or even a different tune.
You built a high performance motor so what did you expect.....Cadillac quiet? Won't ever happen without losing a bunch of power.
http://www.drdyno.com/
Elite HDF Member
Joined: Jul 2007
Posts: 4,749
Likes: 16
From: sand mountain Alabama
Once you obtain a certain amount of of power by doing what you posted the exhaust may have a serious effect on the power. It may have better low end but hurt the upper end and there are many more differences that may rise.
A retune is necessary in a lot of the cases. Each exhaust has different characters, such as low end power vs upper end power. I ran into this when my header broke on my 113. As I was waiting on the replacement I used a different set of exhausts. It made a big impact on the power ranges. Before the power was great all the way up to 6,000 rpm's but with the different exhaust the low end was very surprising better but had to shift at 5,200 rpm's the upper end was hurt pretty bad.
I had a set of the old style SE mufflers on my ultra. They were by far one of the best sounding mufflers that I have ever heard but lost a lot of power
A retune is necessary in a lot of the cases. Each exhaust has different characters, such as low end power vs upper end power. I ran into this when my header broke on my 113. As I was waiting on the replacement I used a different set of exhausts. It made a big impact on the power ranges. Before the power was great all the way up to 6,000 rpm's but with the different exhaust the low end was very surprising better but had to shift at 5,200 rpm's the upper end was hurt pretty bad.
I had a set of the old style SE mufflers on my ultra. They were by far one of the best sounding mufflers that I have ever heard but lost a lot of power
Last edited by dirtdobber; Oct 12, 2014 at 03:13 PM.
Extreme HDF Member
Joined: Nov 2007
Posts: 14,670
Likes: 139
From: East of the Sun, West of the Moon
Once you obtain a certain amount of of power by doing what you posted the exhaust may have a serious effect on the power. It may have better low end but hurt the upper end and there are many more differences that may rise.
A retune is necessary in a lot of the cases. Each exhaust has different characters, such as low end power vs upper end power. I ran into this when my header broke on my 113. As I was waiting on the replacement I used a different set of exhausts. It made a big impact on the power ranges. Before the power was great all the way up to 6,000 rpm's but with the different exhaust the low end was very surprising better but had to shift at 5,200 rpm's the upper end was hurt pretty bad.
I had a set of the old style SE mufflers on my ultra. They were by far one of the best sounding mufflers that I have ever heard but lost a lot of power
A retune is necessary in a lot of the cases. Each exhaust has different characters, such as low end power vs upper end power. I ran into this when my header broke on my 113. As I was waiting on the replacement I used a different set of exhausts. It made a big impact on the power ranges. Before the power was great all the way up to 6,000 rpm's but with the different exhaust the low end was very surprising better but had to shift at 5,200 rpm's the upper end was hurt pretty bad.
I had a set of the old style SE mufflers on my ultra. They were by far one of the best sounding mufflers that I have ever heard but lost a lot of power
but dirtdobber is correct. anytime you get into more airflow in and out then components become more critical to match your build.
Thread Starter
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Advanced
Joined: Aug 2013
Posts: 95
Likes: 6
From: Lafayette, LA
After going through all the service records and receipts, this is what was done to it:
Vance and Hines dual exhaust headers (Unknown muffler type)
Engine Bored and Stroked to 103 ci
Screamin Eagle Pro Twin Cam MCR Performance Heads
Screamin Eagle 1550 Stroker Pistons
Screamin Eagle 258 Cam
Oil Cooler
Power Commander and lots of dyno tuning
Road Warrior
Joined: Apr 2010
Posts: 1,648
Likes: 37
From: Monroe, Louisiana
Best bet is to get it retuned. If it is popping anywhere except decel it is too lean. If just not pulling right down low it is likely too rich. These are hard to detect unless it is just popping. If the power loss is at wide open throttle then the 100% area is likely 5 or 6% too lean and not likely to rich as the Rineharts should be flowing pretty well. You may even try some torque cones at the heads to see if that would help. Best thing is to just get it retuned.
Outstanding HDF Member
Joined: Jan 2008
Posts: 3,328
Likes: 15
From: Pacific Northwest
Years ago, at Sturgis, I watched Dr. Dyno doing that exact thing in a set of straight pipes on a bike ridden from a guy from Colorado. With no other changes, the increase in results on the dyno were amazing. He used a thumb style bolt, which could easily have it's position in the pipe changed to increase or lower back pressure.
http://www.drdyno.com/
http://www.drdyno.com/
Doing that to a set of straight pipes is one thing.....but fokking up a nice set of mufflers is quite another particularly when a different set of baffles will produce the desired result.
Seasoned HDF Member
Joined: Jan 2011
Posts: 157,521
Likes: 57,072
From: Michigan 15 Minutes East Of Hell
Yep ... Yes Sir Ree ... A B S O L U T E L Y !!!
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Cruiser
Joined: Jun 2006
Posts: 147
Likes: 0
From: Virginia
Interesting discussion. I have a '14 SGS that I put 4" RHs on without changing anything else. It's not popping, but I wonder if it will gain from a remap. I realize I could do the AC and a remap, but dealer quoted $700 for that and I didn't see a great need. I also don't want a louder system. To be honest, I probably should have tried the stock exhaust for a while. I still may.
Agree you should be able to find a pair of "quiet" baffles to try with your system.
Agree you should be able to find a pair of "quiet" baffles to try with your system.
Road Captain
Joined: Oct 2006
Posts: 660
Likes: 4
From: Ft. Smith Arkansas
RC Xhaust best performing and sound on the market!
http://www.rccomponents.com/rcxhaust...t-slip-ons.htm
http://www.rccomponents.com/rcxhaust...t-slip-ons.htm