This exhaust features 3 stepped header starting at the heads with 1-3/4" tubing then steps to 1-7/8" tubing and to a 2" tubing. This makes up the equal length primaries that join into a 2.55" collector and then into the 4.05" muffler body. The header is ceramic coated inside and out and features dual O2 bungs (18mm & 12mm). The Dragula also comes with a choice in baffle and is good for up to 120 HP. The 2.55" is good for 145 HP and the 3.05" is good for 280 HP. This exhaust system comes standard with a choice of a slash tip that can be turned up, down, inward or outward and heat shields. We offer a 2 year warranty on the construction of the exhaust and we also offer a ghost pipe to achieve a true dual look.