Abit of a rookie question. I would have thought both exhaust pipes using both mufflers would work better than one muffler each ? How much gain can one expect from "true duals"?

 

Actually no gain at all. More of a loss really. The stock head pipes and mufflers on any HD will give better HP and TQ gains than any 2-2 set up. If you really want to change it up for better sound and better power you need to look at some of the better 2-1 set ups. D&D and SuperTrapp comes to mind. There are at least two more worth looking at but not many more than that.

 

I have read a lot about true duals and reckon there is a bit of urban myth in the supposed loss of performance. I have Samson pipes with S&S oval mufflers on my S&S V107T and am getting the HP and TQ output in S&S's brochure. I wrote to them to ask if true duals are OK, before fitting them, and they said they are one of their approved set-ups. Their brochure shows 97HP and 103TQ, mine is giving 102HP and 103TQ, but with 8k miles up now feels stronger than when I had it dynoed.

I like the looks, it gets rid of that siamese pipe, sounds great and works fine, thanks!

 

great info

 

Expect NO GAIN ! The best tuned exhaust I have seen is the two into one setup.With having said that the reason I like true duals is that I can easily see how each cylinder
is performing by looking at the exhaust,such as blue smoke from one pipe and not the other.It makes it much easier for me to do diagnostics.

 

i run the stock head pipe ans s.trapps on my 127" evo,tried a buddies true dual on the dyno last summer,lost alot of torque,hp a little but pretty much the same

 

Compared to stock head pipes, expect a low-end torque loss and no better than no-gain in peak-HP, probably a small loss there too if your engine is stock. TD's are popular because they eliminate heat on the right-leg of the passenger and rider, and have a pleasing stereo tone.

IMO, performance-wise TD's are on the low-end of the performance spectrum, followed by stock head-pipes with conventional mufflers, stock pipes with Fuel Moto Jackpot (asymmetrical) mufflers, and finally a 2-into-1 system. The Jackpot mufflers emulate a 2-into-1 by their design, which restricts the exhaust emitting from the left muffler.