Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

[TheChad]

Re: Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

What is a jackplate?<br /><br />Well Right now we are getting 42-43 MPH. As long as I can keep no less than 40MPh I am fine with that.<br /><br />I called the dealer I purchased the boat/engine from yesterday, and he said he had another customer with the same boat, that was having the same problem. Couldn't get the boat to go in plane while pulling a tube, the dealer said the customer called Lowe and Lowe told him to Lower the motor down on the transom...<br /><br />Weird...<br /><br />I am thinking to go down to a 17p prop, and possibly raise the engine up on the transom 1 hole.. I am waiting for the local dealer to call me back with a price to move the engine on the transom...<br /><br />-TheChad

 

[procraft180]

Re: Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

I would try raising the motor before I started dumping money on props. If you had your motor raised and still not achieve the performance you were looking for, then find a good prop shop that will let you test different props prior to purchasing. You might find out that raising the motor will be all that is necessary to achieve the better hole shot and top speed. You might find that a 19p SS prop is the ticket, maybe not, depends on the boat. I didn't have the luxury of a prop shop that had the props I was interested in. i took a gamble and purchased the Turbo, then spent $30 to have the engine raised, luckily, it worked out as I had hoped. Just got lucky maybe?

 

[procraft180]

Re: Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

Take the time to test and get a good baseline and go from there.

 

[TheChad]

Re: Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

$30? That'd be nice. I called around, it will cost me $75-$100 to get my engine raised.<br /><br />There is one dealer near one of the local lakes that says he has a QuickSilver 17P Aluminum prop, and an 18P Mercury Vengeance SS prop, He said I could intall it and take it to the lake and try it out, if not what I need, he will trade it for another...<br /><br />The Dealer that has the props said he didn't think moving the engine up would make much of a difference, but Should be done after the prop change if at all... <br /><br />It's hard to know what to do... I just want it to work correctly!<br /><br />-TheChad

 

[walleyehed]

Re: Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

The Dealer that has the props said he didn't think moving the engine up would make much of a difference, but Should be done after the prop change if at all... <br />

Chad, I can promise you right now, the Dealer that told you this should be avoided...Obviously, he knows NOTHING about set-up...Never change the prop until you've maxed what you have FIRST.<br />On another thread, we have a gent that raised only 1 hole, picked up 300R's and about 3MPH...this is a very positive reaction to raising the engine...not all will gain "that" much, but 75-100R's per hole is usually the case.

 

[procraft180]

Re: Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

That was me WH. I wasn't expecting such gains either, but I am not complaining.

 

[Ron G]

Re: Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

Listen to Kenny.and for the dealer he sells props sounds like he's looking to make some cabbage off of you.

 

[TheChad]

Re: Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

LOL. I got Mercury Marine Telling Me to raise the engine up one hole.<br /><br />I got You guys Telling me to raise the engine up one hole.<br /><br />I got Lowe telling me to lower the engine down one hole.<br /><br />I got 1 dealer telling me to leave it in the 2nd hole.<br /><br />I got 1 dealer telling me to move it down one hole.<br /><br />The only thing everyone seems to agree on is that I will want/need to change props to an 17p or 18p.<br /><br />My god, I don't understand why there is soo much different information going around...<br /><br />None of the dealers seem to be on the same page.<br /><br />The only thing I can think of is maybe I need to go to a couple of dealerships and try talking to one of the tech's instead of the service guy that works at the desk..<br /><br />*Frustrated*<br /><br />I wish it was something easy that I could do my self, then it wouldn't matter, because I could just try everything, to find what ever works best, and not spend $75 a pop to have it moved.<br /><br /><br />I understand both point of views...<br /><br />By raising the engine up, you get less drag, but according to one dealer, you will have less trim, and wont be able to tuck the engine under as far which will cause the bow to lift up worse than it does now. Which i guess makes since to a point... (This same dealer also said You shouldn't have to trim more thain about 1/4 on the trim guage, but at my current 2nd hole from the top, I trim the motor almost 1/2 way on the trim guage)<br /><br />By Lowering the engine down, according to another dealer will give you more bite, and more trim to tuck under the boat, which will be better for tubing/skiing.. This also makes since, but would create more drag.<br /><br />According to BoatingLife They used a 13P prop, and got 42 MPH at 6200 RPM, which would be about right on the RPM scale since my 19 Pitch only gets 5200RPM. But 42MPH? Must have only been 1 person... From the pictures on that review, their engine was mounted on the top hole (All the way down). But on the specs it says they used a 13x19 prop, but there is NO way they got 6200 RPM with a 13x19 prop, so I have to assume the editors notes that says they used a 13 pitch prop is correct.<br /><br />-TheChad

 

[TheChad]

Re: Prop Diameter & Pitch Questions - 115hp EFI 4-Stroke

Well, I have called all the local dealers within 45 minutes of here and none of them were able to raise the engine up for 1-2 weeks.<br /><br />We are going to Lake Kentucky next weekend.<br /><br />So I found a dealer that had a Mercury Vengeance 18 Pitch Stainless Steel prop in stock for $365.<br /><br />So I went and purchased that prop. OMG what a difference!<br /><br />I was getting 5500-5700 RPM, and doin 47-49MPH!!<br /><br />At to get the 5700RPM and 49MPH, I had the engine trimmed way up, On the trim guage it was above the 1/2 way trim, but it wasn't slipping.<br /><br />A more reasonable trim was just below 1/2 trim I was getting about 46MPH and turning 5500 RPM.<br /><br />But either way it was a HUGE difference. It was like letting the beast out of its cage.<br /><br />I think a 17p Stainless Steel prop would be perfect, but the dealer only had 16p and 18p, a 16p, we both thought would be too low causing over rev.<br /><br />-TheChad