Aftermarket exhaust vs. HP and torque...
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Tourer
Joined: Nov 2010
Posts: 255
Likes: 2
From: Athens, AL
Aftermarket exhaust vs. HP and torque...
I have a question....perhaps the guys from Rush and Samson will know OR some of the tuners here......
Generally it is documented that a good 2:1 exhaust will provide the best horsepower/torque for a given tune all things being equal... My question is....Where do the REST of the exhaust types fit in? For instance....I have OEM headers with Rush 1.75 baffle slip ons on my Softail Deluxe..... I would LIKE to go with V&H/Samson true dual baffled fishtails.... Stage IV kit will be here next week for install.. Would the duals cost me performance wise? Stick with the Rush slips ons or go with the true duals for best performance?
THANKS!
Generally it is documented that a good 2:1 exhaust will provide the best horsepower/torque for a given tune all things being equal... My question is....Where do the REST of the exhaust types fit in? For instance....I have OEM headers with Rush 1.75 baffle slip ons on my Softail Deluxe..... I would LIKE to go with V&H/Samson true dual baffled fishtails.... Stage IV kit will be here next week for install.. Would the duals cost me performance wise? Stick with the Rush slips ons or go with the true duals for best performance?
THANKS!
Outstanding HDF Member
Joined: Apr 2009
Posts: 2,523
Likes: 3
From: Illinois
You're going to have a million people tell you that true duals will kill your low-end torque, I say it's bullshit. I'm running Rinehart true duals with a stage 1 and cams, and I'm getting just short of 90 HP, and over 104 TQ. Looking at my dyno sheet I don't feel like I'm lacking anywhere. That being said, I think you "could" lose some low-end depending on what kind of duals you're running. I can only speak for Rinehart's because that's all I've ever used, but I'm sure there are some others that will hurt you for "peak numbers" and that kind of thing. And I really want what I want, and if that does cause me to lose 2-3 HP or TQ, I don't care. The numbers are just for bragging rights anyway.
Road Captain
Joined: Aug 2005
Posts: 576
Likes: 1
From: Southern Maine
I agree. Get the pipes that have the look or sound you want. I have samson true duals with rush 1.75" mufflers. I prefer the look of the true duals with one on each side. I don't have anything to compare to performance-wise.
Seasoned HDF Member
Joined: Feb 2008
Posts: 22,999
Likes: 11,439
I have a question....perhaps the guys from Rush and Samson will know OR some of the tuners here......
Generally it is documented that a good 2:1 exhaust will provide the best horsepower/torque for a given tune all things being equal... My question is....Where do the REST of the exhaust types fit in? For instance....I have OEM headers with Rush 1.75 baffle slip ons on my Softail Deluxe..... I would LIKE to go with V&H/Samson true dual baffled fishtails.... Stage IV kit will be here next week for install.. Would the duals cost me performance wise? Stick with the Rush slips ons or go with the true duals for best performance?
THANKS!
Generally it is documented that a good 2:1 exhaust will provide the best horsepower/torque for a given tune all things being equal... My question is....Where do the REST of the exhaust types fit in? For instance....I have OEM headers with Rush 1.75 baffle slip ons on my Softail Deluxe..... I would LIKE to go with V&H/Samson true dual baffled fishtails.... Stage IV kit will be here next week for install.. Would the duals cost me performance wise? Stick with the Rush slips ons or go with the true duals for best performance?
THANKS!
As for TD the cost you some power but not enough to worry about with a good tune and some baffles in the slipons.
there is no magic one correct way to go.
Ultimate HDF Member
Joined: Jan 2008
Posts: 6,532
Likes: 132
From: SoCal
If you ever have a look at ANY high performance internal combustion engine you will see that ALL non turbo/super charged engines will have a collectored header with merge collectors, the individual exhaust header pipe "Zoomie" on a N/A motor has not been seen for 40 years. Think you know more than the best in the business about performance......you don't! TD's will lose TQ and HP , if you like the looks great, but to argue they perform just as good as a quality 2-1 is complete nonsense.
Tourer
Joined: May 2009
Posts: 432
Likes: 2
From: SW of Fort Worth
I've spent the past year trying different dual systems comparing them to the D&D Fat Cat Boss 2 into 1 system.
I will not mention specific brands/models because I know there are those who will argue until they are blue in the face I am wrong. But, I know what I know, not from hearing from a friend, or from running a set of duals that felt good, etc.
My conclusion is after actual riding and tuning. I am all about total power/torque throughout the power band. I have a cam that produces good strong flat profile. And you can see what exhaust I have back on my bike from my signature.
I will not be spending anymore money trying different dual systems. Its as simple as that.
That said, a 2 into 1 systems have their sound. Duals with different mufflers all have their own sound. If you are more inclined to choice which exhaust you go with based on sound rather than performance....I just have one thing to say to you. You wanna race????
I will not mention specific brands/models because I know there are those who will argue until they are blue in the face I am wrong. But, I know what I know, not from hearing from a friend, or from running a set of duals that felt good, etc.
My conclusion is after actual riding and tuning. I am all about total power/torque throughout the power band. I have a cam that produces good strong flat profile. And you can see what exhaust I have back on my bike from my signature.
I will not be spending anymore money trying different dual systems. Its as simple as that.
That said, a 2 into 1 systems have their sound. Duals with different mufflers all have their own sound. If you are more inclined to choice which exhaust you go with based on sound rather than performance....I just have one thing to say to you. You wanna race????
Outstanding HDF Member
Joined: Apr 2009
Posts: 2,523
Likes: 3
From: Illinois
I've spent the past year trying different dual systems comparing them to the D&D Fat Cat Boss 2 into 1 system.
I will not mention specific brands/models because I know there are those who will argue until they are blue in the face I am wrong. But, I know what I know, not from hearing from a friend, or from running a set of duals that felt good, etc.
My conclusion is after actual riding and tuning. I am all about total power/torque throughout the power band. I have a cam that produces good strong flat profile. And you can see what exhaust I have back on my bike from my signature.
I will not be spending anymore money trying different dual systems. Its as simple as that.
That said, a 2 into 1 systems have their sound. Duals with different mufflers all have their own sound. If you are more inclined to choice which exhaust you go with based on sound rather than performance....I just have one thing to say to you. You wanna race????
I will not mention specific brands/models because I know there are those who will argue until they are blue in the face I am wrong. But, I know what I know, not from hearing from a friend, or from running a set of duals that felt good, etc.
My conclusion is after actual riding and tuning. I am all about total power/torque throughout the power band. I have a cam that produces good strong flat profile. And you can see what exhaust I have back on my bike from my signature.
I will not be spending anymore money trying different dual systems. Its as simple as that.
That said, a 2 into 1 systems have their sound. Duals with different mufflers all have their own sound. If you are more inclined to choice which exhaust you go with based on sound rather than performance....I just have one thing to say to you. You wanna race????
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Outstanding HDF Member
Joined: Apr 2009
Posts: 2,523
Likes: 3
From: Illinois
If you ever have a look at ANY high performance internal combustion engine you will see that ALL non turbo/super charged engines will have a collectored header with merge collectors, the individual exhaust header pipe "Zoomie" on a N/A motor has not been seen for 40 years. Think you know more than the best in the business about performance......you don't! TD's will lose TQ and HP , if you like the looks great, but to argue they perform just as good as a quality 2-1 is complete nonsense.
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Banned
Joined: Sep 2009
Posts: 7,580
Likes: 7
From: The Internet (& Dyer, Indiana)
For starters your statement is not correct the 2 to 1 will in most cases if tuned correctly provide more low end torque, but it will cost you dearly on the top end.
As for TD the cost you some power but not enough to worry about with a good tune and some baffles in the slipons.
there is no magic one correct way to go.
As for TD the cost you some power but not enough to worry about with a good tune and some baffles in the slipons.
there is no magic one correct way to go.
However, true duals on a bagger generally perform fairly well with a good tune. Certainly better than stock pipes.
If the look and sound is important to you, it'll be worth sacrificing a few ponies.
I run a Fatcat myself after years of experimenting. Not my favorite sounding pipe, but definately performs well.
Road Warrior
Joined: Dec 2008
Posts: 1,733
Likes: 38
From: Linden, NC
Now, you mention stock Harley 2-1-2, which is not a fair comparison due to the catalytic converters they now install in their pipes. Throw a pair of any aftermarket true dual head pipes up against a Fullsac, Fuel Moto Jackpot or ridiculously priced Wegner X pipe (priced from $1700-$1800 w/mufflers) with the same mufflers and you should see a marked advantage to the 2-1-2 systems.