(polished shown)
Power+Plus Cyclone Manifold is a direct replacement manifold for the stock manifold on Chevy big block engines with general duty oval port heads. See note below for specifics.
This manifold will not fit under the hood of Corvettes without hood modifications. Will not fit "tall block" V8s. May be used with OEM or aftermarket carburetors.
For street applications use the stock Quadra-Jet carburetor. For Street Performance use a 650-750 cfm performance or double pumper carb and for Competition use a 700-850 cfm double pumper. Note that the Power+Plus Manifold kit includes a carb adapter plate and gasket to allow the use of square bore carburetors. Square bore carbs on this manifold are not legal for use on any emission controlled vehicle.
Use a Fel-Pro #1210 or #1212 intake gasket with this manifold.  

Note: This is a stock replacement/street legal part for 396, 402, 427, and 454 V8s with OEM 4-bbl carb; 1965-'72 (1973 non-CA) passenger cars and 1966- '83 trucks, Suburbans, and heavy vehicles; except stock equipped EGR.