Quicksilver revolution 4 prop

[Sloopinn]

Interested if anyone has or is running a quicksilver revolution 4. I’ve got a 150hp Yamaha 4 stroke left hand rotation. on a 6.5 m ribtec with a 19 pitch Yamaha stainless Steel propeller an I can only rev the engine to 5200rpm an achiev 39 knots. The man at my local boat yard who is a Yamaha engineer and races boats for a hobby has advised me that ideally my engine likes to rev and I should be trying to get as close as possible to 6000rpm for maximum performance and drop down to 17 pitch as propeller. I use the boat for all round fun wakeboaring, towing inflatables sight seeing along the Cornish coast and blasting across to the isles of scilie occasionally. Just looking to get better performance as I think I should be able to get another 5 mph top end. Any advice or views please.
Thanks Matt.

[charliee]

I have a 6.6m Cobra with an F150a and was told the best prop, by numbers is the black painted Yamaha M19, which I think is 14 1/2 inch and is stainless despite not being shiny. As an alternative Cobra fit the Reliance series 14¼” x 18pitch S/S prop, its a start but best to wait to hear from other Ribtec owners.

[Sloopinn]

Thanks for your reply,what revs do you managed an knots?

[charliee]

I think 5850, not sure on top end always too much weight in boat!

[Sloopinn]

Is your engine cavitation plate level with the bottom of your boat? Mine is at the moment but going to raise it a couple of inches which supposedly should help with performance?

[Frar]

Swapped out a 3 blade 21" pitch for one of these on a 6.8m running Mercury 175 2 weekends ago. Delighted with it. Higher speed (20% higher at 4k rpm,), better economy ( c. 15%), no problems getting on plane with additional adults in boat.

Only bought boat this year so no expert and can't say for sure if the props great and the old setup was just wrong or not.

[gtflash]

I run a rev4 on my etec 250. I own two a 21 and a 25. But that’s another story. The 25 replaced a three blade 26” when I wasn’t achieving WOT.

You don’t say what prop you have currently. if you have a 3 blade. Adding a blade usually adds 300ish rpm. Most people who add a blade drop down 1-2” size. Reducing prop size by 1” usually gains 200-300rpm roughly.

On my old boat 7.5m scorpion. I ran a 21” laser, swapped to a trophy, then a bravo, then a high five, finally a 19” rev4. Amazing grip and acceleration, best speed out of the lot, gripped the water in the rough so engine didn’t over Rev.

Current boat on 3rd prop. I don’t think I’ll ever be without a rev4 now.

[gtflash]

Ps lifting engine up will increase rpm. But watch out for water pressure or over heating. The plate in line with keel is old school default. Lots of engines will run higher but eventually you will loose acceleration and cornering. It’s free though. My prop shaft is level with bottom of my boat, damn thing only ever got on the plane with the waves behind it, till I fitted rev4

[Sloopinn]

I think I’m going to go with a 17 pitch 3 blade ss prop for now and raise the engine a couple of inches an see how I go at that. Just looking to get the revs up to nearer 6000RPM mark an try to achieve 40 to 45 knots. At the moment boat handles an corners really well with good exceleration. The 4 blade props are coming in at over £500 so hoping to pick up a 2nd hand ss 17 inch for under £200 fingers crossed. Just done a complete refurb and new power steering so have to tighten the purse strings for a while.

[gtflash]

Even second hand a rev4 is wrong side of £200. Smaller ones usually cheaper.

Raising the engine usually gives revs before you buy a new prop in my experience.

[Sloopinn]

I rang solos props today for a bit of advice and he thinks for what I want higher revs more top end that dropping down to a 17 and raising the engine a couple of inches should do the trick. New solos ss prop with fitting hub £370 😥