How far out should they stick...

[morebeanz]

...the exhausts, that is! I've seen lots of differences, but I wonder what would be an ideal distance in relation to the bumper lip?

I am making the assumption that too long leaves them exposed to damage, but probably too short could give rise to fumes entering the cabin/windows or scorched bodywork.

[gbbird]

I've noticed this too. I haev always assumed it depends on the type of Sports exhaust you have

[SXS]

Also dont forget, when the whole system heats up, the rear pipes do also tend to extend out further, rule of thumb, go for a level with lip end fit, and expect it to grow about 2 inches when fully heated up.

[spartacus]

SXS said:

Expect it to grow about 2 inches when fully heated up.

2 inches! We are talking about sports exhaust here?