Thank you RodKnock for holding the floor me
No question the BB potential for HP is greater than SB, never in dispute, SB is limited to about 460 CID max, BB can go substantially higher.
As for zippy, there is Big Brother (BB) zippy, and his Smaller Brother (SB) zippier.
Good note to end on, anyone can start a new thread to discuss the zippy family further should they want to
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