More stray thoughts. Part I's '87 18 originally powered by a V-4 Johnson 112/115, slightly underpowered, in his opinion. Rebuilt V-6 Johnson 150, not sure of GPS WOT. Much happier.
My '79 20 MA originally powered by Merc. 200 BM blew up 1 hour after seatrial. Repowered 1999 V-6 carbed Johnson 175. ($600 for 200 HP carbs. (not necessary!)), not sure of GPS WOT. Much happier
The 20 is only minimally faster. Guestimatation: Both running very close to 50, light load, one occupant and trimmed. Both 15" transoms, and stock floor heights. Neither have T-top, trim tabs, or Porta- Potties. However, both do have fully stocked adult beverage coolers!
NOTE: We share a Jersey Speed Skiff, we guestimate closing in on 70 GPS, but thats unofficial as well. Stop down the LowCountry! Mike.