Hi Soberdude!
TOR hypocritically stands for "Triumph Off Road" (sic), i.e. ex-factory, dealer-supplied, warranty-compatible optional pipes. They look just like the standard ones but produce a definitely more authoritative sound, without being obtrusive. NOT street legal in most countries, i.e. those with enforced noise regulations (hence the "Off Road" disclaimer up-front). Require a dealer-performed engine tune change. But then all after market pipes do.
I never used the standard pipes. Had the TOR's installed from the start and then switched to the australian Mad Dogs (while keeping the cat box). Deeper and at the same time mellower sound, although, yes, decibels went up, and beefier appearance. Am quite pleased with them
Hope this helps.
Jamie -Oct. '04 green Rocket III-