LS7 Ported and Polished Cylinder Heads (Parts Only)An option for those who only want to fix their stock GM LS7 heads, these are the same heads we use for our LS7 Heads Cam packages. Race Proven Motorsports Custom Spec'd CNC'd Ported and Polished LS7 Cylinder Heads w CHE Precision Bronze LS Valve Guides, . 660 Dual Valve Spring Kit, Manley LS7 Solid Stainless Steel Exhaust Valves Pricing includes a $2,000 charge that will be refunded if your stock heads are returned. Cylinder head cores must be