Prop selection

[dahman01]

I have a 13.75x21 now on a 89 maxum with a 5.7 and run 4200 RPM at wot but I do not have a very good hole shot and thought about going with more pich but 21 is a big pitch will it hurt to go more or stay with this prop???

 

[tommays]

Re: Prop selection

you need LESS PITCH the motor if runnning correctly should run about 4800 rpm <br /><br />did the boat ever run at higher rpm or was 4200 allways max<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=36;t=000030 <br /><br />this is good prop info from the faq section<br /><br />tommays

 

[dahman01]

Re: Prop selection

this was the original prop on the boat when i got it bout original on the boat not sure? what pitch would you get to have a good hole shot i am not to worried about top end speed as much.

 

[tommays]

Re: Prop selection

its really trial and error the boat should reach its nameplate WOT with its normal load to give the best performance<br /><br />i am asking how well the motor runs because if its in good shape and tuned well it should have no problem with 13.75 x 21 the next size down is a 14*19 and that seams small for a 5.7 motor<br /><br />how big is the boat<br /><br />tommays

 

[Wart T]

Re: Prop selection

How big is the boat and what is the typical load in it and what is the boat used for?

 

[dahman01]

Re: Prop selection

sorry guys just getting back busy week the motor runs good it may need a tune up the plugs are a little bit black. The boat is 20' and with 4 people it just dont want to get up to plain it is used to ski and tube.

 

[tommays]

Re: Prop selection

well you can try a 14*19 its the next size smaller and will give a better hole shot<br /><br />if you have not done a tune up in a long time i would try that first 5.7 is plenty of motor for a 20 foot boat i have a 1995 maxium 20 ft with a 3.0 and it will push the boat just fine i think it would jump out of the water with a 5.7<br /><br />tommays

 

[dahman01]

Re: Prop selection

Thanks for the help.