Harley Davidson Forums banner

1 - 8 of 8 Posts

·
Registered
Joined
·
13 Posts
Discussion Starter #1
On 2 into 1 exhaust systems compared to true duals , I wanted to switch to duals but was told the other is better all around for performance and sound , is there truth to this or is it preference ? What would any of you recommend? Thanks
 

·
Registered
Joined
·
556 Posts
My understanding that unless you have done all the work with high lift cams, and intake work, then duals are better. But if you just want the sound and keep good gas mileage, then 2 into 1 is better because each exhaust helps pull the other cylinders exhaust. Kind of like creating that initial vacuum to pull the exhaust. Much more efficient. Otherwise each cylinder is pushing the exhaust on its own through a long travel through the headers and mufflers. A short exhaust is better for duals because the exhaust gases can exit more quickly. But that takes an ignition timing mod, etc. I installed the Vance Hines on my 1200C Sportster and got the sound I wanted without sacrificing the original performance and fuel mileage.
 

·
Registered
Joined
·
11,033 Posts
I agree with the better performance with the 2 into 1, but I don't agree with the better sound of the 2 into 1 than duals.
Exhaust dynamics can be quite complicated. And I ain't smart enough to argue this point, but I remember reading an article, which after the first few paragraphs I couldn't fully comprehend it all, that summed up the power issue regarding 2-into-1-into-2 versus true duals. In summary the article ended up saying that under WOT true duals will give the best performance.

And after listening to a lot of bikes at local bike nights it is my opinion that true duals have a better sound than both 2-into-1-into-2 and 2-into-1.
 

·
Banned
Joined
·
71 Posts
Exhaust dynamics can be quite complicated. And I ain't smart enough to argue this point, but I remember reading an article, which after the first few paragraphs I couldn't fully comprehend it all, that summed up the power issue regarding 2-into-1-into-2 versus true duals. In summary the article ended up saying that under WOT true duals will give the best performance.

And after listening to a lot of bikes at local bike nights it is my opinion that true duals have a better sound than both 2-into-1-into-2 and 2-into-1.
TruDuals lose low end torque but gain high end HP .


:biker:
 

·
Registered
Joined
·
13 Posts
Discussion Starter #6
My plan is to upgrade the exhaust on my 13 switchback I wanted to go with the true duals from vance & hines the (only company I can find that makes them ) for this bike I like the looks of duals , along with upgrades on air intake and a screaming eagle tuner and have it dyno tuned to run proper I don't plan on doing cams at this point . while I was checking into it at the dealer to see what they could do the tech directed me to d&d fat cat and showed me a bike with it , it sounded great had a clean look so I am not against it and was told with what I want to do and if I ever decide to do cams that pipe is better and more cam ready . Off to the parts counter and that guy says he is not impressed with the duals because of quality issues he has seen and says he don't care for the fat cat either and recommends the vh pro pipe , now I am not sure what to do :thanks
 

·
Registered
Joined
·
1,967 Posts
:thumbsup
My plan is to upgrade the exhaust on my 13 switchback I wanted to go with the true duals from vance & hines the (only company I can find that makes them ) for this bike I like the looks of duals , along with upgrades on air intake and a screaming eagle tuner and have it dyno tuned to run proper I don't plan on doing cams at this point . while I was checking into it at the dealer to see what they could do the tech directed me to d&d fat cat and showed me a bike with it , it sounded great had a clean look so I am not against it and was told with what I want to do and if I ever decide to do cams that pipe is better and more cam ready . Off to the parts counter and that guy says he is not impressed with the duals because of quality issues he has seen and says he don't care for the fat cat either and recommends the vh pro pipe , now I am not sure what to do :thanks

RB RACING - LSR Header (2into1)
 
1 - 8 of 8 Posts
Top