2013 glastron 205 GT 4.3

[Bschick]

Looking to drop from a 19 pitch 4 blade to a 17 pitch just don't know if I should go with a 3 blade or 4 blade anybody have any suggestions.... I am currently running the 19 pitch 4 blade prop still seems to be a dog out of the hole with more than two people in it .. wide open throttle is 4400 RPMs gear ratio is the 1.62. the engine I am running 4.3 MPI MerCruiser... All props I am using are aluminum....

 

[alldodge]

Howdy
Rule of thumb is 4-blade pitch should be 2 inches of pitch lower then a 3-blade
4-blade 19 = 3-blade 21 or go the other direction if going up

Current WOT should be closer to 4800

Going to 4-B 17 should bring your rpm up at least 200 rpm maybe a tad more which will put you closer to max range. I would suggest a 3-B 19

 

[QBhoy]

Hi. I wouldn’t give up on a 3 blade just yet. Are you trimming up at wot ? I know of a 19ft bowrider with the same engine and gear ratio. He had a 21” 4 blade spitfire on it. It would do 46 mph GPs and on the limiter at 4950 rpm. We then put a 19” 3 blade tempest plus on it of mine. Just to get him by, while he waited on a 21” stainless. We were amazed to see that the 19” was literally perfect for it. 51/52 or so gps at 4830 rpm on the smart craft. Tachometer said 5000 rpm but they don’t usually tell the truth. I wouldn’t go as low as a 17” unless you want to hit the limiter when wot and trimmed up.