Exhaust Mod- PSE

[tifosi00]

I want to do the hack that Pedro (ppbon) on PPBB has done, to make the exhaust like the Porsche Sport Exhaust. I just have one question, I am assuming the exhaust is made of steel, so does anyone know what I need in order to weld the steel? Do I need a welder or an acetylene torch?

here is the link to what I want to do:
http://www.ppbb.com/boards/ppbbphp/showflat.php?Cat=&Board=ARCHIVES&Number=1067764&page=8&view=collapsed&sb=5&o=7&fpart=1

Thanks!