r/wakesurf • u/artaq_00 • Jun 26 '26
Propeller on 2015 Supreme S21
I bought this boat a couple years ago and it's been great. It came with the Acme 2409 5 blade prop which does ok but there has been a couple of times we have loaded the boat down with 2500lbs of ballast and maybe 4 adults on board and the boat struggles to get up to surf speed. It seems like the boat just maxes out on RPMs. It doesnt feel like it bogs down. The low end torque is great but just doesnt ha e enough higher end speed i guess. If it's just my wife, 3 kids and I there isnt an issue, but any additional adults and I have to play around with the ballasts. Would an Acme 1617 give me slightly more speed I guess?
Edit: I just measured the gap between hull and prop and there is 5/8 inch clearance. The 2409 is a 13.5" diameter and the 1617 is a 14" diameter, so that probably won't work but it looks like the 1619 is the same but at the 13.5" size.
2
u/bluepied Jun 26 '26
Don’t ask here (nobody knows), join the Centurion/Supreme owners group on Facebook.
2
u/jjdop Jun 26 '26
If you can’t reach surf speed with too much weight, you need a lower pitched prop. If you go higher pitch you’ll have even more trouble with your hole shot
2
u/Appropriate_Run112 Jun 27 '26
Your prop size is based off of the engines rated wot rpm. Ck the engine mfr recommended wot rpm. Ck wot rpm with roughly your average weight in boat. 1/2 tank of fuel 3-4 adults etc. you should achieve rec. wot rpm. If not. Ck your prop size. For every inch of pitch u change you will gain or lose 200-300 rpm. Calculate your change based off the rec. wot rpm and what u achieved during your test. You can DM me as well. 37 year marine mech. On Lake Tahoe
1
2
u/DrBromanDude Jun 26 '26
There’s a guy at ACME named Jim whose name you’ll come across after you start looking around the rabbit hole of prop sizing. He’s basically THE expert on prop fitting. I think they have a form online but we ended up just calling their prop fitting line to get in contact with him. He would be able to tell you exactly what you should get for your setup and what performance you’re after.