View Single Post
  #19  
Old 01-20-2017, 12:16 AM
Bushwacker Bushwacker is offline
Senior Member
 
Join Date: Feb 2007
Location: N. Palm Beach, Fl.
Posts: 2,456
Default

Quote:
Originally Posted by doradohunter View Post
. . . Anybody with a bracketed 20 wanna hang some weight on the bracket and report back to me on ride and rest?
My Baseline: I ran a 300 lb motor on the transom for 31 years, including 6 trips and 2500-3000 miles to and from the Abacos in the 1-2' square waves common to the Little Bahama Bank. (Lots of water runs on and off the hundreds of square miles of the Bank every 6 hrs, creating a current-against-the-wind and short steep chop conditions in the 10-20' deep water.)

I then changed to a 429 lb motor on a 30" Hermco bracket, so I've learned first hand about the effects of engine weight and brackets, which is why I posted the thread on the pros & cons of brackets. Very few folks on this forum have run a 20 as long as I did with a light motor on the transom, so I've probably noticed the effects of brackets and heavy motors more than most. Trust me, the 20' hull rides incredibly well when balanced as designed!

At the dock, my Seafari sits about 1" lower in the water at the transom with the bracket and heavier motor and is just barely self bailing with the lower deck of the pre-'73 models, thanks to the big flotation tank on the Hermco bracket. Remember that the Seafari is about 200 lbs heavier than a CC model, and the extra weight is all up front, so I'd expect a CC model to sit a bit lower with the same changes.

Because of the significant aft shift in CG with a new configuration, I immediately noticed a SIGNIFICANT DETERIORATION in low speed planing performance and in ride! Min planing speed went from 12 mph with the light motor to 22-23 mph with the new motor and bracket! By adding some band-aids (a stern lifting 4B prop and fin on the AV plate), I was able to get min planing speed back down to 12 mph, but the fin causes extra drag, and 4B props are typically worse than 3B props in both cruise mpg and WOT speed. However I moved the motor back another 3" when I installed a jack plate to get motor height correct, and even that small change, which shifts CG just like a heavier motor would, made the boat more prone to porpoising and more sensitive to engine trim and weight distribution.

In summary, I believe the safety benefits of the solid transom, the convenience of the swim platform and extra room gained by eliminating the splashwell are worth the compromises caused by the required band-aids. However if you plan to add a bracket, recognize up front that you're making a significant change to the boats CG, so I recommend trying to minimize the CG change by using the lightest possible motor!
__________________
'72 SeaFari/150E-Tec/Hermco Bracket, owned since 1975.
http://i188.photobucket.com/albums/z...Part2019-1.jpg
Reply With Quote