Ford Racing teamed up with Jon Kaase to redesign their 429 Cobra Jet cylinder heads, and the results are these Super Cobra Jet heads. They feature revised valve angles and locations to reduce cylinder wall shrouding and improve flow, along with redesigned combustion chambers to accommodate the more centrally located valves. These heads use the same valves, valve springs, retainers, and 716 in. stud - mounted roller rockers as the current Ford Racing 429 Cobra Jet heads, and the standard Cobra Jet intake and exhaust manifolds bolt right on. This new design offers a 25 - 50 HP increase over current Cobra Jet heads, depending upon displacement and camshaft.