[Steve C.]

"Tanzi also noted that “to yield the greatest gains requires header design work....Matching primary tubes with regard to the intake manifold and cylinder head ports is also necessary. This usually relates more directly to applications that use a single-plane manifold, and tunnel ram manifolds in particular. In terms of fuel distribution, we see greater benefits with single-plane manifolds as compared to dual-plane manifolds, since dual-plane manifolds are less prone to
reversion and negative pulsation.”


https://www.motor.com/magazinepdfs/032009_07.pdf


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