V8 Gurus..., Edelbrock Manifold and Head miss-match Options

[neo914-6]

Why don't the water passages match on these? Both are Edelbrock Performer parts...

[Rgreen914]

QUOTE (Neo914 @ Apr 3 2005, 07:26 AM)

I figure it is designed this way but the center galley made me ask the question. The gasket I removed had an opening but the one I just bought has none. That wouldn't have a symetrical issue being in the center.

That opening in the center of the manifold is for exhaust heat to pass under the plenum in the manifold, for smog compliance and/or cold drivability concerns; from the pic, it appears that your heads don't even have this heat riser port open. Some gasket sets come with the gasket opening for this heat riser but include a small tin block-off plate to allow you the option of "plugging" this opening. The coolant passes from the block, through the heads and then out the thermostat housing in the front of the manifold. It doesn't pass out the rear of the heads due to the location of the distributor; some racers will, however, install fittings and a hose to allow circulation between the heads in that area. Some smog manifolds also have coolant flowing beneath the carb/TBI plenum location.

Ron