posted 7 years ago
For the 6" system, your CSA (cross sectional area) is just over 28"sq, so for the manifold you want to allow for more than that to avoid a bottleneck where the exhaust flow makes a turn from flowing down the barrel. Make sure there is at least 3" clearance between the duct and the riser too, to prevent restrictions.
Drying out the system will help with draw, just double check clearances in the manifold first to be sure it's more than enough CSA.
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