Chevy “Double Hump” Cylinder Heads

Chevy Double Hump Fuelie Heads

492 “double hump” head with “Undercover Porting” and angle milled. Note the spark plug cooling holes were plugged before the angle milling

The “double hump” or “fuelie” heads have been around since the 1960’s. They are still used in a variety of applications. We have a good supply of used ‘186 & ‘492 heads available with everything from “Undercover Porting” to CNC Sportsman Porting.

Stock “double hump” heads flow 202 cfm intake and 141 cfm on the exhaust. If you must maintain a stock looking port, consider our “Undercover Porting”. With our “Undercover Ported” they will flow 220-230 cfm intake and 165 cfm exhaust. This flow improvement will add 15 to 25 horsepower to your engine.

CNC Ported ‘492 Head.

We may be the only company around with CNC programs for the “double hump” heads. An option to consider is to use the aftermarket Dart heads with a disguise package to resemble the original “double humps”. The Dart heads offer superior air flow to the early “double hump” heads. Masters of Disguised Heads.

Intake Manifolds – Most of the classes that run “double hump” cylinder heads run a cast iron intake manifold. We have everything from acid ported to fully ported cast iron intake manifolds that work terrific with “double hump” heads.

Stage 1 Intake. Over 20 horsepower gain @ 6,000 rpm vs. a stock intake manifold.

Fully Modified Q-Jet intake. 40+ horsepower gain vs. a stock intake


Part #

Complete “Double Hump” heads with “Under­cover Porting“.  Assembled with 11/32” stainless steel valves, flat tappet springs, spring locators, steel retainers, machined locks, rocker studs and guide plates. Flat surfaced to your specifications. 

“Double Hump” castings, bare, machined for screw-in studs, new guides & “Undercover Porting“.



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