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Discussion Starter #1
ok so we want a system that is tuned. it will decrease back pressure & increase scavenging.
primary tube length: shorter lengths add torque above peak hp rpm point & reduce torque below it. longer lengths add torque below peak hp rpm point & reduce torque above it
. equal tube length will ensure balanced exhaust flow (tall narrow torque curve).
un equal length primary tube headers produce a flat broad torque curve
primary tube diameter: smaller provides higher flow velocity = better scavenging
. larger diameter provides higher flow volume.
tube bends are bad, they slow down velocity. they should be mandrel bent.

but what i want to know is... whats better 4 2 1 header or 4 1 header?
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