Designed for Ford 429/460 competition engines using Cobra-Jet cast iron, SVO Cobra-Jet aluminum (M-6049-A429), or the Edelbrock 460 CJ aluminum heads. Both manifolds are ideal for drag racing (Super Stock, Super Gas, Super Comp, Brackets, etc.), marine or any application requiring maximum power up to 8000 rpm. Standard 429/460 cast iron heads will require port matching of the head to fit manifold. Our 1" Cloverleaf Spacer #8718 provides maximum performance with #2965 where hood clearance is not a problem. Port exit size at head is 2.16" x 1.88" with enough extra material to open it up to the cast iron Cobra-Jet heads. Will not fit late-model production heads (1988 & later).