I think the difference is what some of us call "alot" of difference. My tuner told me a better exhaust, especially a good 2 into 1 could get me "alot" more low end tq than the 109 ft/lbs that I have.

I asked him how much "alot" was, he said as much as 2 or 3 ft/lbs.

That's not "alot" to me, but to some it is huge.

Dennis

 

Not sure about the altitude, but I put Bassani True Duals omn my 95" Road King, and definietly lost power. Personally would never spend $ for them.