Just installed a Permatrim on a C-22

N

NC-TFC

New member
I just took our 22 Cruiser out this weekend after installing a Permatrim hydrofoil on a 90hp Yamaha 4-stroke with an aluminum prop. I'm pleased with the performance, our experience is similar to what's been described here before. Better tracking and steerage, faster up on a plane, slightly lower top speed. I usually run at around 4300rpm and would get 22mph, now it's around 20.5mph.

I am curious how much trim tab others add with a Permatrim? I know its somewhat subjective based on boat loading etc. I usually keep the fuel tanks topped off. I used to run with the tabs fully down to get the bow down as much as possible. If I do that now the bow runs much lower than before but I'm not sure I need that much. I'm also wondering if a Stainless prop would alter the performance at all?

Opinions on the best combination or experiments to find out would be appreciated
 
I installed a permatrim about a month ago and at the same time changed to a stainless prop. As far as the trim tabs I usually only use them for side to side trim. If I want to trim the bow down I usually do it with the motor but in smooth water and a balanced load I operate with neutral motor trim (permatrim parallel with bottom of boat) and no trim tab. You can experiment with different combinations while watching your tach or mph to get the optimum preformance. With my Suzuki 90 I get my best economy either below 1500 RPMS or above 4600. I like the stainless prop mainly for it's durability. My motor is set a little low and next time I have the boat out I'm going to raise it one hole. I understand with the stainless prop you can run the motor a little higher which I hope will provide better economy. I'm running a 14 x 18 prop which is a little over pitched and may have and inch of pitch taken out. Of course these prop specs won't be good for your Yamaha because of the difference in gear ratio.
 
NC-TFC wrote:
I am curious how much trim tab others add with a Permatrim? I know its somewhat subjective based on boat loading etc. I usually keep the fuel tanks topped off. I used to run with the tabs fully down to get the bow down as much as possible. If I do that now the bow runs much lower than before but I'm not sure I need that much.
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The answer also depends on how much 'down trim' you are running on your motor. I have twins, haven't measured the angle exactly, but I estimate maybe 15 degs down trim. Then I add trim tabs to produce the desired fore/aft and lateral trim for best performance. For my twins, I really like the Permatrims, seems to support the extra weight of the motors better than the excessive amount of trim tab angles I had to use before, which as a side effect, makes my steering so much easier.
 
Thanks for the advice. I too have about 15 degrees of down trim. I took a test ride last night and keeping more down trim on the motor let me bring the trim tabs up. Steering was definately easier and the boat still planed at a good angle. The more I use this combination the more I like it.
 
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