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1968 Corvette originally 427 currently
1974 Gen IV Big Block Approx 500hp / 500Tq
I bought a set of side pipes and would appreciate some feedback on exhaust manifolds and would provide sufficient airflow. What is the spacer block on the 3880828 manifold? Do I need it? Do I need the exhaust extensions that go from the manifold to exhaust? They are approximately 2” long.
1968 Corvette originally 427 currently
1974 Gen IV Big Block Approx 500hp / 500Tq
I bought a set of side pipes and would appreciate some feedback on exhaust manifolds and would provide sufficient airflow. What is the spacer block on the 3880828 manifold? Do I need it? Do I need the exhaust extensions that go from the manifold to exhaust? They are approximately 2” long.
The "spacer" is required to fill the space when the heat-riser valve is removed. The right hand manifold is shorter to allow for the valve depth but when it's not used, you have to fill the space. The extensions are very useful for aligning the required donut gaskets when assembling. If you don't use them the gasket can get skewed out of alignment and leak gasses. Much better to use than not if your pipes are flared to accept them.
One more thing... be careful bolting the manifolds to the block as the ears are relatively fragile. If the manifold and block don't have parallel mounting surfaces you'll break off an ear or two if you torque too much to close a gap.
1968 Corvette Exhaust Manifold Question
