Offenhauser Small Block Dual-Port Dual-Plane Spread Bore intake manifold

Offenhauser Small Block Dual-Port Dual-Plane intake manifold for a square bore carburetor with thermostat housing... Great low and mid range torque and power for a small block... Great throttle response and MPG... Perfect to wake up a stock or moderate cam 318 or 360 in a car, truck, or van... .

$250 OBO + shipping from southwest Chicago... Local pickup preferred...


Here's some comments from someone who ran one:

It was kind of a 'super' dual-plane intake manifold.

I was impressed with the engineering design concept of the small primary runners for high-velocity intake charges and the isolated larger secondary runners for a cooler intake charge when the carb secondaries opened up. Being smaller than a full intake runner also kept the cooler secondary charge at a high-velocity.

My 340 was built to the extent that it required a Holley 850 double-pumper to keep it fed or it ran out of gas on the top end. All I can tell you is it worked and it ran strong.

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