Is the a big jump in hp and tq between the true duals and the slip ons. Lets just say the same slip ons will be on both bikes.

 

I believe that you loose some torque with the duels, not sure about hp.

 

I have rinehart TD with a PCIII and got almost 9 lbs of torque to my rear tire. Not bad for TDs.

 

This may help answer your question?

http://www.nightrider.com/biketech/exhaust_test_02.htm

 

I've dyno'd my bike for hours at a time testing pipes (have a VERY supportive tuner that lets me play). My test subjects when I was messing with duals were SE's and Wild Pigs. While I saw differences in the curves, my "area under the curve" was nearly identical between duals and stock headers with either mufflers, and peak HP and torque numbers were close enough for the differences to be statistically insignificant. My overall impression based on the shape of the curves and the tuning required, was that I was going to stick with stock headers - but this was a personal choice and I could make a case either way.

Please note that I properly tuned the bike for the configuration that was being tested. Any time someone tells you they swapped something out and gained horsepower, your first thought should be "how out of tune were you beforehand?" Magazine articles are a perfect example.

So, my experience tells me that there may be reasons to go to duals (heat, reduce decell popping, sound, looks) but performance is not one of them all other things being equal.

 

Not really. That's good information (expecially to the knuckle-draggers that like drag pipes) but it does not compare the same mufflers in both configurations.

 

I gained a little torque and HP going from stock pipes and Rolling Thunder mufflers to Bassani Tru-Duals and Rush mufflers (2.5" baffles). However, the bike's performance changed significantly. With the stock pipes, torque/acceleration was smooth and constant. With the Bassanis, acceleration is quicker and at around 3000 rpm it feels like a turbo kicked in. This is a link to the dyno sheet comparing the 2 configurations: http://i50.photobucket.com/albums/f3...I_20070731.jpg

 

Hey now. I like my drag pipes.

 

Thanks guys. Has anyone tried the V/H slip ons and then added the true dual set up?