I have a 2016 Triton TRX 189 with a Evinrude 150 H.O. ( Gen 1) which came with a Raker H.O. ( 14.5"X 22"). Boat runs very well with this, speed and RPM's match closely, 61mph & 6000 RPM's at WOT. Decided to get a 4 blade for rough water. I have minimal experience with props so I spoke to several experts and received the following recommendations:
1. Evinrude RX4. 22 pitch, without needing modification
2. Mercury Revolution 4. 20 pitch, would need modification
3. Mercury Racing Bravo 1 FS. 23 pitch, without needing modification.
A few friends went from a 3 blade smaller diameter prop like the Raker to a RX4 with a 1" lower pitch. All were unhappy with performance.
I was suggested that I speak to someone from Mercury Racing who advised the Bravo above. Purchased it and had very poor performance-Max RPM's 5300 and 53 mph speed, trimmed all the way up. Also, could not find a "sweet spot" where the steering loosened up.Mercury took the prop back and sent me same model with 20 pitch. RPM's went to 5800 but no increase in speed. Didn't realize that the Bravo has a 15.25" diameter , which is 3/4" more than my Raker. I expected some loss in my top end but not 8 mph. I won't be able to return the Bravo, which I ran once . Any suggestions would be appreciated. Thanks.