Hello Jock1,
I have had a 96 cube in and FLHRC, and a 103 in an Ultra, both I modified with the V&H PowerDuals. The reason is that on our local Dyno, the PowerDuals generated the most power on before and after testing, of about 10% HP added....
However, since then, I have done some more experimenting with the stock pipes as the PowerDuals hang a bit low below the frame and scrape on any hump in the road on a right hand turn... I also like the look of the stock pipes. In short, we have now charted almost the same results as the PowerDuals, with the Cat Gut of the stock pipes. With the catalytic converter out: The stockers have a bit of Venturi effect that extracts the cleaning cylinder with the exhaust stroke of the compression cylinder of the 4 Stroke, the same way as the PowerDuals. I give some pictures of the how of it, in a Topic about ten down from this one, you might what to have a look at: Surprising Dyno results, for cut out Cat on Tourer.
It also keeps the clean lines of the stock pipes... You might want to have a look at that Topic, as I like the set up now in performance as well as the V&H Powerduals, and personally I like the looks even better.. Hope it is a help, at least worth a look...
