I have an 18 footer Sea Ray which we fill up to the max with weight to get a half decent wake. When it's that heavily loaded planing takes forever so I am looking into getting a new prop. Has anyone tried a 4 blade prop with this engine/boat (3.0 liter 135 HP)? Does it help at all? Any info appreciated. <BR> <BR>Please no remarks about just getting a wakeboard boat cos I'm not balla and this is all I have for now. Cheers. <BR> <BR>(Message edited by slamminp on April 06, 2007)

I had an 18' Grew (narrow boat) with the 3 liter in it. Mine was old and had 170 Hp. It became good when I put a hydrofoil (Mine was a Stingray) on and a four blade stainless mercury prop. You can find shops that will let you demo a prop. My 4 blade worked better than the High 5 I tried. I wound up staying with a 21 pitch that I'd had in three blade but if you load heavily you would want to drop the pitch. Check your RPM and don't overrev if you drop it several steps. <BR>I'd put on the hydrofoil before I spent the money on a prop. Good Luck

The Stingray helped my 18' Reinell plane faster. I agree with Art try the Hydrofoil first.

Doesn't the hydrofoil decrease the size of the wake like crazy?

I am not sure about the hydrofoil decreasing the wake, but I know it helps shape it better and helps the boat plane faster. I also think you should go with the Mercury Highfive prop (5 Blade SS). It is by far the best holeshot prop. You can get a pitch that is lower so you can help get that heavily loaded boat on plane. Heavily loading a 3.0 liter sounds interesting... I bet it really drags its ass. I guess it all depends on altitude. Here is Colorado it is like the special Olympics trying to get our boats out of the hole.

Mikka, the best thing about the hydrofoil is the ability it gives your boat to hold a speed. You can trim up a little as soon as you are at speed and find you have a bigger better shaped wake.

Thanks guys. The reason i asked about the hydrofoil is that its whole purpose is to lift the boat out of the water to get it on plane right? So logically the boat would be higher up and displacing less water making a smaller wake. <BR> <BR>That five blade prop looks crazy, I might just try it out. <BR> <BR>Recommended max weight for my boat is 900 lbs and I'm loading this thing with 1400. The wake's pretty good when it finally gets on plane!

I have a Sea Ray 200 select with the Bravo III outdrive ( 2 counter rotating 3 bladed props). I recently attached a Stingray Sr. Hydrofoil to my cavitation plate and WOW- what a difference. I can actually see over the bow while sitting in the driver seat at all speeds. It helped plane the boat faster (it was around 4.5 seconds to full plane before)and now it is almost immediately. The top end speed of the boat increased by 5 mph. The boat is now VERY stable in rough water too. All of my friends have commented how smooth the boat is in the water now. This is the best 50 bucks (give or take)you can spend on your boats ride provided you have an I/O style boat. I am still anayzing gas mileage and that is around a 7-8% increase. The wake is about the same except for take off (it is less now because the boat is getting on plane faster) <BR> <BR>We are being ripped off at the gas pumps anyway!! (sorry- I had to say that)<img src="http://www.wakeworld.com/MB/Discus/clipart/uhoh.gif" border=0>

Merc makes a 4-blade aluminum prop for about $180 vs. a High-5 for $600? I think the 4 would work better in a 3.0. Go down in pitch. If you're running a 19P, then go to their 18P or even 16P if thats not enough.

I got a 2000 searay 18 ft same motor and i got the hydrofoil and thought it made a big difference. I got a 17 pitch 3 blade prop and it works great with 750lb bag and 4 people. I asked a guy at a boat dealer about getting a new prop because i was gonna get a 4 blade or 5 but he told me to stick with the 3 for some reason. He also told me to get a stainless steel prop because it makes a big difference, just make sure you dont hit anything. How do you weight your boat, like i said i got a 750lb bag in back and want to add more but not sure how to weight it. <BR> <BR>(Message edited by luke22885 on April 07, 2007)

Back in my I/O days I ended up with an 18" pitch 3-blade.

I'm weighting my boat with 540 lbs in the back and 220 in the bow. It only starts getting bad with about 3 people or more. <BR> <BR>Anyone mind elaborating on how changing the pitch affects performance and hole shot?

Lowering the pitch changes the torque multiplication of the engine through the drive. That is going from a 19 pitch to a 17 pitch gives you your power times 19/17 or roughly 12% more punch out of the hole. It also means that your engine at top speed might run 12% higher, so you have a better chance of over revving your engine.

The hrydrofoil will help plane it out,(less water displacement) making the wake smaller but you can trim it up sinking the back (more water displacement) once you're up on step. <BR> <BR>So yeah, it'll be a smaller wake out of the hole but you should still be able to get the same AOA "Angle of Attack" by trimming it up. <BR> <BR>Hopefuly that made sense. Or am I wrong?

Miika go with a lower pitch 4 blade and watch your tach on takeoffs/no full throttle take offs.

The first step is getting a prop with the correct pitch. I run a 3 blade SS 17P on my Merc 3.0 I/O and it tachs out about 4400 and has plenty of low end, although I haven't added any weight yet. You can go down in pitch 2" and you should pick up about 400 RPMs, but you have to be careful and not overrev your motor. 4 blade props help somewhat on takeoff but they really shine in preventing cvavitation and prop blowout which shouldn't be a problem in an I/O unless you are taking extremely sharp turns at high speed. <BR> <BR>I also run a hydrofoil which helps with low speed planing. It doesn;t seem to effect the wake very much since I can trim up and sink the stern to throw a steeper/bigger wake. <BR> <BR>One thing that can be done IF you have a SS prop is to have vent holes drilled on the trailing edge of the hub. This will allow exhaust gases to enter the prop blade area, causing it to ventilate and spin up faster upon takeoff. This is very common for bassboats andflats boats who run higher pitched props but need help on takeoff. I wouldn't suggest this route until you talk to your local prop guy about how it might effect your situation. <BR> <BR>(Message edited by uncc_grad on April 10, 2007)

I think the maximum rated RPM for a 3.0 is 4200 which is fine, you just don't have to run full throttle so the boat is a little quieter at the maximum RPM. That said, I had run mine to 4800 many times before I got the maximum numbers for the engine, with no apparent damage.