Trick Flow® R-Series A460 Tunnel Ram Intake Manifolds were developed for all 8,000 plus rpm applications such as drag racing and tractor pulling. They feature a 2-piece design with interchangeable top covers so you can mount either single or dual Dominator-style carbs. They're made from thick-wall A319 aluminum for durability and the lower manifold feature bosses for nitrous and fuel injection nozzles. The lower manifold and top covers are sold separately; both pieces are required to make a complete manifold assembly. R-Series A460 manifolds can only be used with Trick Flow® PowerPort® A460 series cylinder heads.