if you can just turn 1,4 bends circled inward a tad it you wont
need extra pipe. Just direct straight pipe to the sides of the
2,3 pipes. Leaving 2,3 squashed up will keep both side separated
without the need of a baffle. 2 YY like will flow very well and
make less welding. Reversion is a terrible waste of flow otherwise
regardless if the valve is closed on the other end or not.
Jmac also suggested in a previous thread to make the flange outlets
not matched ported but 1mm larger so if the pulses reverse they hit
the 1mm smaller exhaust port head face. Jmac can clear this theory up.

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