with aggressive camshaft profiles headers high performance ignition systems etc ... ratio 280° or more of cam duration and headers with 1-5/8 primary tubes being a mid ... 200-800 rpm for best results the use of headers and a performance ignition system is ... used primarily in drag racing tractor/truck pulls and performance marine ... runner style designed for the 5.0l ford and ls series families these intakes ... intakemanifold tm p/n 300-111p p/n 300-64 p/n 300-14 efi series single plane ...