Flange: Chevy 23 Degree
The Howe Iron Lung header was designed to improve the performance of unported or restricted flow heads. Offers the greatest advantage in restricted applications such as no porting or small carburetors. Should not be used with less than 10 to 1 compression or with a baffled muffler. Used in combination with a 2 into 1 muffler, increases of up to 25 hp and 15 ft/lbs. of torque are not uncommon when peak rpms are under 7000. These are a firing order header and should not be installed backwards on the dyno, or modified for use on non-Chevy engines. Use 3.5” collector for more torque and better average horse power, use 3” for greater peak horse power. Built with 3/8” thick CNC flanges.