SuperTrapp Open vrs Closed Trapp Caps
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Cruiser
Joined: Mar 2007
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SuperTrapp Open vrs Closed Trapp Caps
Does anyone have hard data showing the differences in performance between using the open end cap and the closed end cap?
I recall hearing or reading somewhere that if you were going to use the open end cap you'd have to reduce the number of discs by "X". Can't recall how many discs X represented.
Any ideas?
FuelMoto guys - is there anything you can tell me / us.
Thanks,
T
I recall hearing or reading somewhere that if you were going to use the open end cap you'd have to reduce the number of discs by "X". Can't recall how many discs X represented.
Any ideas?
FuelMoto guys - is there anything you can tell me / us.
Thanks,
T
Elite HDF Member
Joined: Mar 2006
Posts: 4,722
Likes: 5
From: Biddeford, Maine
The open endcap is equal to 6-8 discs. I used to have a chart showing the difference direct from Supertrapp, but I think it got deleted since I can't find it anywhere.
I found the closed endcap to be too quiet and with a "phffft" sound to it, and I found the open endcap to be too blatty.......so I sold the exhaust.
Steve
I found the closed endcap to be too quiet and with a "phffft" sound to it, and I found the open endcap to be too blatty.......so I sold the exhaust.
Steve
Outstanding HDF Member
Joined: May 2007
Posts: 2,673
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From: Norfolk, VA
On the Supertrapp forum they claim the open end cap is worth about 10 disks of flow. That is what I removed when I went with the open end cap, but I have not had it back on a Dyno so I cannot tell you if it is accurate or not.
Cruiser
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Found this on another site but the person said the Super trap said 10 disks on a closed cap equals 2 on a open. This is how i have mine set up on a 09 tri glide and 2010 road glide and they are about equal sound wise. the road glide has more of a growl to it when you get on it but both sound great. can hear radio fine on both bikes but a lot deeper sound than the stock pipes
Outstanding HDF Member
Joined: Jun 2007
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From: Cocoa Beach, Florida
I did it (for a minute) and lost throttle response, lost a LOT of throttle response. Way too little restriction for the baffle only even with a stock head-pipe and CAT. Went to the open end-cap and ended up at 5 disks installed too.
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From: Biddeford, Maine
The disc system works on backpressure created by the endcap, so by removing the endcap you are defeating the discs on the muffler.
I found that a closed endcap and more discs worked better for all around power......and it was a bit quieter then other exhausts.
With all the sound **** laws popping up now, I'm thinking about getting a Supertrapp again to quiet things down......and I'll be running a closed endcap with 18-20 discs.
Steve
Outstanding HDF Member
Joined: Jun 2007
Posts: 2,542
Likes: 2
From: Cocoa Beach, Florida
The disc system works on backpressure created by the endcap, so by removing the endcap you are defeating the discs on the muffler.
I found that a closed endcap and more discs worked better for all around power......and it was a bit quieter then other exhausts.
With all the sound **** laws popping up now, I'm thinking about getting a Supertrapp again to quiet things down......and I'll be running a closed endcap with 18-20 discs.
Steve
I found that a closed endcap and more discs worked better for all around power......and it was a bit quieter then other exhausts.
With all the sound **** laws popping up now, I'm thinking about getting a Supertrapp again to quiet things down......and I'll be running a closed endcap with 18-20 discs.
Steve
Last edited by RangeRat; Sep 6, 2010 at 08:03 AM.