Re: Tunnel Drive Speed and Wake?
To the folks that are supposed to know it all about Penn Yans, you haven't a clue.
The single biggest reason that a Penn Yan with a tunnel drive acts like I have read above is; the original engine was replaced with and engine of different rotation. The running gear rudder, strut and even the prop is set up opposite of the way boat was designed.
Second, you have a rough bottom, and are losing hull efficiency due to roughness.
It angers me greatly when some folks want to reengineer something they know nothing about. This is the hull design that was used in Vietnam on many of the river boats, and they are planing hulls, not semi displacement.
You have to take into consideration that these are bery heavily built hulls. I will agree the tunnel is not the most efficient combination when looking for fuel efficiency or subsonic speeds. Propped properly, maintained properly, they are about as good at any of the above description as any standard inboard with a gasoline engine in it.
I can take my 24' Penn Yan in 14" of water and not hit bottom, I cannot do this with my 16' skiff with the engine down. The Penn Yan has some trade offs, speed for shallow depth capability, extreme comfort in heavy water, for lower gunnels and poling depths of the bottom.
To my knowlege there is no one boat that has so many inherent options available to it, as it came off the showroom floor. And to boot, mine is 33 years old, safe in 5' to 6' seas plus, and not beat you to death doing it.
In my years I have seen all kinds of hairbrained concoctions hooked up on this boat. My only opinion of 99% of these was there were no advantages gained by making these changes.
If you want a speed boat get a Fountain with 4 - 250 HP across the back. If you want speed in shallow water get one of those wave maker things.
I seriously have nothing against either displacement or semi displacement powered boats for fuel economy you will have to go an awful long way to beat them. But you lose the off the floor shallow depth operation.
My Penn Yan, will get 30 MPH at 4400 RPM's everyday all day until the gas runs out. I can get 3 mpg at 3000 RPM's and 20 or so MPH I can stay on plane at almost 2200 RPM's never checked the speed, when coming off a higher plane speed. I can even adjust the speed and trim tabs to ride the swells coming into shore. Lot's of fun to do. And if you become proficient at it, can be an effective fuel saving technique.
Straight inboards do not back where you point them. They back almost straight with some torque correction. When you become proficient backing one, you are getting started towards becoming a coxwain.
Yes the 23' Flying bridge feels top heavy to some. It is a very short boat for a FB, actual length 22'8" Again it is a trade off, Penn Yan did make a center console boat, not that puppy can go faster than you can control, and because of the reduced weight is better on fuel economy at higher speeds.
I would suggest that those folks that think they know it all own and operate a PY for a goodly number of years before knocking something they have no clue about. Marine mechanics that are converted automobile mechanics with little or no undersatnding about the beast they are working on.
We do have 2 sites of our own, if you care to learn about this great boat. If you aren't willing to learn then don't bother.
Most of the guys that have repropped use OJ or Acme props, and all Penn Yan Boats 24" and less, have Borg Warner 1:1 Velvet drive reversers.
