Well Roush certainly makes a manifold that fits the cleaveland heads, but I'm really not sure if that is it or not, or if it will fit your heads. The dual plane will give you more low end power and the single plane will give you upper rpm power. I have a Roush single plane manifold on my car and it is a nice manifold. I have the C302B aluminum heads. Maybe someone with more knowledge on these manifolds can tell you.
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