bertram31.com

That rebuild is well documented on Tony's site.

Not sure if the tunnels are worth it.

The interior layout is spectacular, really opens up and modernizes the look with classic appeal.


Seems to raise fish too

Never seen anything like this interior before.
Not sure if practical, nevertheless unique.
All these non-opening windows may require A/C...

Spectacular cabin layout, comfortable airy space for day trips. snipes boat took some inspiration from that and the Bad Co boat. Love the amount of light coming from the aft bulkhead.

Yannis wrote: ↑Nov 19th, '23, 22:55 Not sure if practical,

.
It's a boat, what does practical have to do with it...lol. I do understand your point Yannis, the design is not conducive to live aboard for extended periods. That said the standard 31 layout is not a comfy boat to hang out on when the weather is not conducive to being outside. This I could see kicking my shoes off, laying back and enjoying a drink looking out. Not like mine sitting upright at a dinette.

Yannis wrote: ↑Nov 19th, '23, 22:55 All these non-opening windows may require A/C...

Opening the hatch and door is often enough where I boat. A small fan can do wonders... However yes, on those hot stifling days, AC would be welcomed.
Opening windows on boats these days is a luxury, many boats today are all done up with glued port holes and small hatches way upfront.

Carl,

You cannot imagine what the opening lower part of the 28 front windows can do for you!

Yannis wrote: ↑Nov 21st, '23, 00:35 Carl,

You cannot imagine what the opening lower part of the 28 front windows can do for you!

I have a well-designed boat, the 31 Bertram. On the 31 both front windows can be opened, along with the sides, not just some small lower portion. As they say "Do it right or don't do it at all".


lol...it's been a while since the last 28 jab.
Yes, having even a small portion open up is a big difference. I thought about solid side windows as they look smart, but being able to open a couple of inches makes a big difference.

I guess he didn't like the 440 yanmars

Modern interior looks good.

Modern interior looks good.
Anything over 370hp in a 31 is wasted.

It would be interesting to know what the maximum horsepower figure is for the 28.

I have yanmar 240’s and the structural supports on the hull are trimmed (lowered) by approx. 2-3 cm so that these motors can fit in the bay, of which the cover closes at a few millimeters from the engine top.
I doubt that any -more voluminous - cat or cummins with more horsepower, could fit in there.

I’m talking max hp, without altering the boat by raising the engine covers etc. I’m also talking diesel, for gas they could fit anything.

If altering the boat from stock is not an option for more hp, how about altering the motor to gain more hp.
Not my thing to squeeze more out of a diesel as I believe it goes against what I think a diesel should be, but I believe it can be done. Pump n injectors modified to push in more fuel, maybe chill it too. Coolers to chill air, upgrade turbo, maybe go twin turbo to push more air in. More air, more fuel makes more power…at the cost of motor life.

You're right, one can push any motor to its limits.

What I was interested to know is what the biggest engine one can put on a 28 is, per manufacturers' data.
I understand, Carl, sadly not everybody has a 28...! LOL

Yannis, I understood your original question and decided to be a pain answering from another direction. Kinda like I want to say “put on a 28”. Well that would be a pair of the OXO 300 hp diesel outboards. They would go on… go in, that I have little idea.

I would think one of the motors similar to your would be the ticket though. Compact, light and high revving, Yanmar, Steyr, Nanni, and Hyundai come to mind. The Cummins 4bTA packed a lot of power from a small space, but do not think available new anymore and I think need a bit of boat tweak to fit. Ask Frank on that. The 6BTA n newer I think like Cats are too big, n very heavy.

So all in all, not much of an answer, but your post did get a bump…

Yannis wrote: ↑Nov 24th, '23, 00:27 It would be interesting to know what the maximum horsepower figure is for the 28.

I have yanmar 240’s and the structural supports on the hull are trimmed (lowered) by approx. 2-3 cm so that these motors can fit in the bay, of which the cover closes at a few millimeters from the engine top.
I doubt that any -more voluminous - cat or cummins with more horsepower, could fit in there.

I’m talking max hp, without altering the boat by raising the engine covers etc. I’m also talking diesel, for gas they could fit anything.

Those 240s are ideal, maybe it’s possible to physically fit something larger.

Bruce wrote: ↑Nov 23rd, '23, 14:36 Modern interior looks good.
Anything over 370hp in a 31 is wasted.

Bruce, What really stayed with me years ago was when Capt Pat said over 37 knots the boat gets up on the inner chines and can become unpredictable and fall off center. Not sure if that was just a passing comment but I remember it as a hard rule. Being that I’m topping out at 36 kts with the 370s, it just seems tunneling prop pockets or going with 3 outboards is not only a waste of money but potentially dangerous. That being said there is a bunch of outboard conversions that get way above that but they’re essentially extending the running surface. Those prop pockets seem to be a big waste.

PeterPalmieri wrote: ↑Nov 25th, '23, 08:13 Bruce, What really stayed with me years ago was when Capt Pat said over 37 knots the boat gets up on the inner chines and can become unpredictable and fall off center. Not sure if that was just a passing comment but I remember it as a hard rule. Being that I’m topping out at 36 kts with the 370s, it just seems tunneling prop pockets or going with 3 outboards is not only a waste of money but potentially dangerous. That being said there is a bunch of outboard conversions that get way above that but they’re essentially extending the running surface. Those prop pockets seem to be a big waste.

I can attest to this with the 25. over 40mph she is riding so high that I basically lose steering. feels very light and is unpredictable with seas and wind.

When Dick Bertram was designing these boats, the motors were much smaller and today's tech didn't exist.
The gent just wanted to win the Bahamas race, the fastest boat to the Bahamas yes, but not the fastest boat per se, I assume.

As a result, all the Bertrams that I travelled and enjoyed, are 35knot boats, max.
From the 20' to the 54', they all cruise happily up to 35. Above that you commence inner discussions on whether you're still sane.
Some modified may go up to, who knows, 40-50kn. So what?

Pete, Cam, that falling sideways off the center of balance must be terrible in those speeds. Could be really dangerous. Because the buoyancy sideways is not what the boat intends or is even designed to do. It might splash like the racing boats that turn upside down and the pilot is jettisoned to the moon...

I believe Jimmy G and Bob Lilco get close to 40 knots. Jimmy said his is still stable at top end. Those are the only ones that I know of that have pushed the envelope.

Now if those Sharrow props, they are working on for inboards work, you might be able to get that additional speed without increasing HP.

PeterPalmieri wrote: ↑Nov 20th, '23, 07:01 Spectacular cabin layout, comfortable airy space for day trips. snipes boat took some inspiration from that and the Bad Co boat. Love the amount of light coming from the aft bulkhead.

Peter, you're right; 65/31 is the other 31 with such a sunny feeling inside and refined in terms of style.
On the other hand I do like more the head forward (and inside it looks comfy and well-lit)

Pete when I first put her in I was close to 38knots WOT it didn’t feel to bad but I didn’t leave it up there for to long. I probably won’t go there very much. I like the cabin windows but the frames when I looked were very pricey if I were to do it again I could build it to accept windows it would just be a ton of work and money.

Tony Meola wrote: ↑Nov 25th, '23, 22:04 I believe Jimmy G and Bob Lilco get close to 40 knots. Jimmy said his is still stable at top end. Those are the only ones that I know of that have pushed the envelope.

Now if those Sharrow props, they are working on for inboards work, you might be able to get that additional speed without increasing HP.

Maybe.. my sharrow is a tie in terms of top end with my standard prop. The magic happens at lower rpms.

Cam

Have you have seen an improvement at cruise RPM's?

yes, and a host of other performance improvements/refinements. It might be worth a thread of its own if folks are interested. Cost aside, the company has been great to work with and the product is excellent.

Cam

It would be an interesting discussion. Especially since they have partnered with an Australian firm to make props for inboards.

Tony Meola wrote: ↑Nov 28th, '23, 22:18 Cam

It would be an interesting discussion. Especially since they have partnered with an Australian firm to make props for inboards.

and...what a Partner!

https://sharrowbyveem.com