need some speed

[1kenwood]

I Have a 1990 bayliner capri 2050 with the 3.0 alpha 1 drive. Typical story..... I bought the little motor now I would like to pull a little top end out of it. I can run what shows to be 38 trimmed out mphs. I know rpm at wot is critical however my tach is not functioning properly. I have a 14 1/4X 17 prop and at wot the motor sounds like it wouldnt hurt much to slow it up a couple rpms. I have good takeoff considering the powerplant, and I know I need to get the tach fixed, also know thats pretty good top end for what I have, but if anyone has any good input I would sure put it to good use. 3 blade or 4? I need to get a backup prop and would like to get one to pull 1 or 2 mphs out at my current rpm without drastically affecting takeoff. Aluminum or Stainless? THANKS FOR ANY HELP GIVEN!!!!!!

 

[mkast]

Re: need some speed

Do not get upset, you aren't going to hear what you would like to hear.
If you increase pitch, for more top end, time to plane (hole shot) will increase.
Using a stainless steel propeller will usually let the engine rev two hundred RPM over an aluminum propeller. The down side to that is some people have a tendency to chew up propellers and a stainless steel propeller will do some major damage to the lower unit when hitting a rock as opposed to an aluminum propeller. The 3.0 has XXX horsepower, that's the limiting factor.

 

[45Auto]

Re: need some speed

You can't make any kind of logical decision on a prop without knowing the RPM of your motor. Basing your decision of where the motor is in it's powerband on the sound is an extremely expensive way to try to optimize performance. You have no idea whether it would be beneficial to let the motor rev higher or whether it is already revving over it's horsepower peak. I guess you can always buy multiple props at $100-$200 each until you get something that you think works.

Seems like it would be much more efficient to buy a new $40 tach ......

 

[peanutbay1]

Re: need some speed

The reality is the 3.0 is a solid little performer but it is no house on fire. I would get the tach fixed and then start from there. I doubt that you will be able to drive a 19p prop with full load in your boat without being terrible out of the hole. I had 3.0's but until I got into my small block V8 I never realized the power difference. Take it from a 25 boat veteran,looking to grab power out of a 4cyl will cost big bucks and never be what you want. I would just enjoy the ride!!!!!