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chain2
05-25-2017, 09:18 PM
ok probably a dumb question...Are the boat hulls the same on both 15" and 20" model transoms of say a wc 14? So cut 5" lower transom for a short leg? What is the advantage of a 15" transom if any? Is it a weight thing for the shorter shaft motor? :thinking-006:thx chain

EZM
05-25-2017, 10:36 PM
ok probably a dumb question...Are the boat hulls the same on both 15" and 20" model transoms of say a wc 14? So cut 5" lower transom for a short leg? What is the advantage of a 15" transom if any? Is it a weight thing for the shorter shaft motor? :thinking-006:thx chain

Lunds are great boats and the ability to get a 20" transom is smart. I don't really know if there is any significant advantage to a 15" transom. If there is, I'm unaware.

I would guess the lower transom and lower engine makes for a lower center of gravity and might be a little more resistant to roll - but these IPS hulls are extremely safe, stable and hard to dig or roll.

The advantage (of the 20" transom) is the ability of the boat to carry a larger (heavier motor) and, of course, brings the stern up a little higher above the waterline (larger freeboard) to reduce taking a wave or chop over the stern and swamping you.

The weight difference is relatively small on the 15" shaft versus the 20" shafts but it is a good idea to set up your specific motor so that the top of the cavitation plate lines up even or about an inch below the lowest point of the hull.

Keep in mind almost every boat will run best slightly trimmed up after you get up on plane - so going with a power trim on smaller boats (if your budget allows) makes a dramatic difference in fuel economy, top speed, stability, smoothness and control which is real nice on those long runs.

A 20" leg would be the "standard" option for this boat and would allow a pretty routine install with the clamp positioned in the fully seated position.

On both SSV's I've owned (both 20" transoms and 20" legs) I had set up in the normal neutral position (did some test runs) and then ended up lifted the motor up to the highest position the slots allowed to get it up to about "even" when the engine was at 90 degrees. Just seemed to work a little better.

I assume the WC and AC models should be similar in set up.

Good luck - I hope that helps.

EZM
05-25-2017, 10:48 PM
One other thing to consider - much easier to find the options like tilt/trim, electric start and other things in a 20" shaft opposed to a 15" shaft model.

And like I said, if the budget allows for the added cost of the trim/tilt option ...... get it !!!!

ROA
05-26-2017, 09:54 AM
Get the 20" transom. There is no difference in hulls between the 15 and 20. I have a wc 14 with the 20" transom and it is a very good boat. The extra 5" height at the transom is really nice

KegRiver
05-26-2017, 05:59 PM
If your motor is matched to your transom there would be no advantages.

In other words, a 15" shaft motor on a 15" transom will preform about the same as a 20 shaft motor on a 20 " transom, all other things being equal.

But putting a 20" shaft motor on a 15" transom is not a good idea. It will degrade performance significantly which is exactly the situation I have with my smaller boat.

There is one big advantage that I know of to having a 20" transom.
That is, when you throttle back suddenly, there is less chance of the wake coming over the transom, which it often will with the shorter transom.

One other thing, many of the older longer shaft outboards were developed for use on sail boats and they did not have a shallow running setting on the tilt mechanism.

chain2
05-26-2017, 06:54 PM
thanks guys

Mountain Guy
05-28-2017, 05:22 PM
I have a 20'' transom WC 14 with a 20 hp long leg merc with trim and elec start. Love it... one advantage is less splash when back trolling.
I can't really think of any advantages to a 15'' transom other than short leg motors are more readily available and a little less expensive.

cube
05-30-2017, 12:33 PM
ok probably a dumb question...Are the boat hulls the same on both 15" and 20" model transoms of say a wc 14? So cut 5" lower transom for a short leg? What is the advantage of a 15" transom if any? Is it a weight thing for the shorter shaft motor? :thinking-006:thx chain

The one advantage of the lower transom is getting back in the boat with out a ladder. Had a friend get thrown from his boat and could not get back in. Just about died of hypothermia. I would get the 20 though my self and have some kind of re-boarding device.