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Old 05-17-2016, 07:52 PM
gofastsandman gofastsandman is offline
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Join Date: Mar 2007
Location: W.P.B. ,Fl.
Posts: 4,586
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Quote:
Originally Posted by Bushwacker View Post
Michael, I added a jack plate because it was the only way to get my motor high enough (AV plate is 6.0" above keel!) without a major change to the bracket, but in your case it's a waste of money IMHO. Increasing the setback on a heavy motor on the 20' hull is bad idea because it will make the boat tend to porpoise, make it harder to plane, tend to hurt the ride, and installing a jack plate is a lot more work than just raising the motor a couple of holes, especially if you have a trailer with a tongue jack on it! Just ask Capt. Terry what hole the 20" E-TEC is mounted in on his '76 Seafari - no trial and error process required! To raise motor, just lower tongue jack, put a block of wood under skeg, loosen lower mount bolts, pull top bolts, then crank up tongue jack till top bolts align with desired mount hole, and then reseal and reinstall bolts.

The Seafari will feel different from a MA, not only because it's a bit heavier with most of the extra weight further forward, but also because the hull is noticeably stiffer in bending and torsion. The cabin top and bulkhead tie the two hull sides together, plus the tall coaming on the sides stiffens it in the fore and aft direction. Sandy has said several times that in a rough chop, my boat has a more solid feel to it than his SF model.

The Viper prop is BRP's bow-lifting high speed prop, good for bass boats, but probably not what you want if running offshore in rough seas where you want to be able to hang on plane at low speed for the most comfortable ride, which requires a stern lifting prop. If the 5800 WOT rpm is accurate, you're underpropped, since the optimum is 5300-5500 for a 2007 motor. My guess is that it's a 14.75 X 17P Viper, P/N 176626 or 763914 (2-piece TBX hub). Should be able to see PN inside the aft hub, just above the nut. Next time you're out, try trimming motor all the way down and see how slow you can run and still hang on plane. A 4B Cyclone, probably a 14.5x15P, will hang on plane at lower speed, have a much stronger hole shot and better mpg than the Viper, although it might cost you a couple mph in top speed.

Since I'm a performance oriented guy, I like being able to monitor a bunch of engine stuff all the time, and I don't think I'd like having to keep pushing buttons to switch a chart plotter back and forth between engine info and chart or depth sounder. My 2 large and 2 small I-Command gauges are programmed allow me to continually monitor rpm, water temp, % throttle, mpg, trim position, fuel level, fuel burned and range on remaining fuel.

The model code translates as follows: D=E-TEC, S=Saltwater Edition, L=20" Shaft (X=25"), SU=2007, F=Model Run or suffix. My S/N is 05147575, so probably earlier than yours and it's a 25" shaft instead of 20", so about 15 lbs heavier than yours. Denny
The Seafari has more beef in many places than the SF. The MA as well with that big box cap.

I can not scream loudly enough how much prop design can affect your smile.
I had a pos house mouse eared Mich Match on Wide OPen when I got her.
She went to the sky on hole shot and porpoised a bit.
Felt like some cruel joke conjured on the island of misfit toys.

When I tried a Mirage +, I thought this cant be happening.
It was that dramatic.
My ass lifted, and she just screwed.

As freaks, we are constantly chasing props.

If you are trimmed in and still losing the horizon on lift off,
you have a bow lifter.

I like getting some speed easily on take off and then come up.
Be nice to your wrist pins please

It`s a SeaCraft, not a Paramount, no need to carry the bow.
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