Prop question

[Dunnville]

I just bought a 28' cruiser with a signal 454 big block in it, my question is this boat came with a 21 pitch stainless prop on it but to me this seems big for this boat, what do you guys think? My boat before this was a 26' four winns vista with the big block and it had a 15 on it.

 

[jestor68]

Re: Prop question

More info is needed to make a recommendation.

What year is the boat.

What make and model; to determine the weight of boat.

What brand of stern drive. Mercruiser, Omc, Volvo Penta

What type stern drive; i.e., Alpha I or Bravo I, Bravo II, Bravo III, etc.

What gear ratio in the drive.

It's possible that a 21 is appropriate, depending on the aforementioned criteria.

 

[Dunnville]

Re: Prop question

Sorry about that its a 1988 wellcraft Antigua with a 454 merc with a bravo 111 in it, but where would I find the gear ratio?

 

[Bondo]

Re: Prop question

Sorry about that its a 1988 wellcraft Antigua with a 454 merc with a bravo 111 in it, but where would I find the gear ratio?

Ayuh,.... What's it's current Rpms at Wot,..??

 

[Dunnville]

Re: Prop question

Not sure I just picked this up Thursday night. What should the rpm be around at WOT?

 

[Sea Rider]

Re: Prop question

On ideal conditions, that is : flat calm glassy, no wind water cond, lightly loaded boat, you must perform a wot trial test to check achieved max rpm for that outing and compare them to min-max wot rpm factory stated for that engine. That way will know if under or over propped and play with prop pitch accordingly to match proper prop to be inside those safe working parameters. You can ruin you engine by lugging or over revving it at wot and not knowing anything about it.

Happy Boating

 

[Bondo]

Re: Prop question

Not sure I just picked this up Thursday night. What should the rpm be around at WOT?

Ayuh,.... I'd think 4200/ 4600 rpms at Wot,..... generic 454,....

 

[Dunnville]

Re: Prop question

Awesome thanks guys..