Re proping my boat

[gecsr1]

Just purchased new 4 blade SS props for my Twin Yamaha 225 4s"s, did alot of reserach, my boat runs Fine and at the correct wot rpm's. with 3 blade 15.25 x 19 cupped props. I heard from a few people that the 4 blade props will give better lift and lower plane rpms. so if I selected the right props (Hoping I Did) after I talked the the prop rep. I can possibly achieve slower plane speed , lower rpm at troll speed, and better idle speed boat handling. The 4 blades are 14.25 x 19 cupped ss wheel. and posibbly better MPG. I get on average 1.5 mpg now, The rep said that going from 3 to 4 blade that either less diamater or less pitch by one 1" would be the best starting point.

any input would be apprieciated, will install them this weeknd and do a few test....

Gary on the "Reel Adventure II"

[Duramax]

Lower plane speed is correct but at higher rpm, better handling at high speed and more stable correct. But you'll loose top end speed, I went from my 3 blade WOT 55mph to 4 blade 45mph WOT, cruising 23-26 knot's 32-3600 rpm(3blade) to 23-26 knts. 36-4100 rpms(4blade).
I'm kinda torn up between the two props. kinda really like the 4blade but went back to the 3blade for better mgp's and top speed of 55mph .
Good luck.

[Bullshipper]

A 4 blade with give you better trim control at lower speeds and produce a torquier punch out of the hole.

But putting more blades in the water adds to the total area of the prop and the amount of friction loss and will usually hurt your top end and fuel economy slightly.