I'm putting pipes on my 98 XC 700 sled this summer, I'm just tring to figure out which one will benifit me better, either a single pipe system /polarisman/../images/users/lifttillithurts/single.jpg, or a twin pipe setup/polarisman/../images/users/lifttillithurts/thumbnail.jpg. PSI claims the single pipe makes 59 hp @ 5500 RPM and 128 hp at 8250 RPM. The PSI twin pipe makes 57 hp @ 5500 RPM and 136 hp @ 8250 RPM. I'm trying to figure out which one to go with to me, it looks like the single pipe has more bottom end, while the twin has more top end, but I heard that twin pipes run hotter. What are the dissadvantages to running it hot, will it cause damage? Also, which pipe would be better if I were to do some engine mod such as porting it out, the single or twin pipe?