V20 Hull Construction

[76GMC1500]

Is the hull of a V20 cored? *I see a lot of talk of replacing stringers, but never anything on the coring material of the hull.

I am asking this question because I own a 1968 Seabird V21. *There isn't that much information about the Seabirds. *Then, I saw a Wellcraft V20 on a ship I was working on. *Tonight, I saw the pictures of one being rolled in the repair forum. *After seeing the bottom of the hull, I have come to the conclusion that the Seabird V21 and the Wellcraft V20 had to have come from the same mold. *The only difference I have seen so far is that the Seabird hull and sides are cored with balsa wood as well as the deck and portions of the cap. *The Wellcrafts seem to share a similar construction except plywood is used instead of balsa. *The Seabird does have some stringers that run about 2/3rds the length of the hull, but seem to be primarily there to support the deck and provide a mounting location for the engine. *I would swear my boat was a Wellcraft if I didn't have the Seabird nameplate that states capacity and such as well as the shadow of the Seabird logo in the gelcoat.

The Seabird may have more deadrise. I haven't measured it yet, but I know the later models had 24 degrees.

Here are some pictures of the boat.

Same bow flare:


Same "step" and chine setup:


Very similar lines. *You may notice the rub rail is straighter on the Seabird, but everything else seems to be shared. *Even the outward bulge of the sides towards the stern.