My brothers new SeaCraft Tsunami

[Islandtrader]

Originally Posted by bigeasy1

I tried several props and ended up with a 15-1/2" x 17 pitch Mirage ss prop.It is about as close as I can get to being the best performer.
My Tsunami has less ponys(350 ci 260-275 hp) than your brothers however,and My outdrive is a Mercruiser Alpha with a 1.65 gear ratio.

Different boat but here are my first set of numbers.

I was able to pick up a Mirage + 3 blade 21 from blue heron...I believe it is a 14 3/4 diameter.

All the numbers are gps smooth water and a mile run through each rpm range. Boat had one person and approx. 40 gals. of fuel. No trim was used (motor and tabs).

Let me say this: instant response and torque on demand. Pulls hard all the way.

Motor is new less than 3 hours in the test. I have a feeling that I may be under propped when the stroker loosens up. Not by much.

rpm- gph- mph- mpg-

1000/ 2.1- 6- 2.8

2500/ 6 - 23.5 - 3.9

3000/ 9 - 29 - 3.2

3500/ 12.5 - 34 - 2.7

4000/ 14.1 - 42 - 3.0

One quick blast up to 50 @ 4900.


I hate to say it, but that was 2 summers ago...hopefully new numbers coming soon.