bertram31.com

I have a 1980 31 Sportfish. Hull number 1700. It has the upper and lower helms and the original layout except for a clear 1/2” thick polycarbonate rear bulkhead that has a “real” door made of the same material. It even has the original Bertram door hardware. I bought the boat with it like that and I...

High Tide Marine out of Hendersonville NC is licensed to sell Bertram parts. I think they have the original chrome plated bronze side steps. They have used parts too. I would start there.
High Tide Marine, 851 Ridge Drive, Hendersonville, NC. 28792 | TEL: 305-743-0269

I replaced my stock rudders with oversize rudders from High Tide Marine. I went back and looked at the photos I took when I replaced them. They look about the same as the ones in the drawings in this thread. They're a couple inches longer than the stock rudders but as said previously by pschauss - t...

The length at the waterline on a 31 Bertram is 27 feet. Take a look in the specs link posted and it is shown in the lower diagram.

The 28 foot measurement is to the bow eye.

Thanks Carl and Tony. A couple answers to your questions. Yes I have a photo tach and correlated my dash tach readings with it it. Why are the engines not going over 3600 rpm? 1) Because that’s where the max hp rating is at. In theory it is the energy required to push the boat over the water at max ...

2018 Peninsular 400TA 6.5L diesels max 310 HP at 3600 rpm

I purchased a B31 Sportfish a little over a year ago. It came with 310 HP Diesels and had 18x18 3 blades on it with 1.5:1 ZFs. The motors maxed out at 3600 rpm and she would only do about 28 knots with the throttles pegged. Under propped. When I hauled her I switched out the original props with 19x2...