PH 4080 XA-XF 302-351 2V Competition Header Precision Laser cut and machined thick flanges to eliminate leaking and warpage. All headers are jig welded for guaranteed fitment and are checked prior to shipment. Comprehensive fitting instructions with V8 sets together with hi-tensile header bolts. Big bore pipes available for most popular V8 models. Emission hook-ups provided where applicable. Primary pipes fitted through the flanges. Heat proof finish tested to 1270°. Secondary and outlet pipes fitted over primary and outlet cones. Pacemaker are the only Australian Header manufacturer to manufacture their products with Pipe Over Cone™ technology copyright number 135712 applies. The advantages of Pipe Over Cone™ technology are there is no protruding pipe inside the collector cone, therefore increasing exhaust gas flow and eliminating turbulence inside the exhaust header. The result is better gas flow and increased horse power.