Prop: Hole shot or top end speed?

[Shane]

For general playing around and comps, is it better to choose a prop for a good hole shot or max out your top end speed?

I can see hole shot good for skiing and such, but everyone wants to go fast With the posibility of being a boater next in the comps I am just curious. Do we really fish any systems large enough to squeeze the last bit of speed out of the engine?

i'd prefer hole shot than top end speed due to the fact the quicker the hole shot is the quicker you will be on the plain.

but i must say speed it good

[madsurfe]

Hi Shane

good all round performance is the best way to go. Your not pulling skiers so you can sacrifice some holeshot but you still need to push some weight as it all adds up once your fully loaded in a tournament and in most cases you are driving a boat with the equivalent of 4-5 people on board.

The best idea is to test some props all in the one session and choose one that still allows max rpm at WOT (Wide Open Throttle). If you overprop ie: too much pitch you will be overloading (lugging) the motor and this increases load on the motor internals, not good for motor longetivity. It can also turn any motor into a highly inefficient fuel guzzling monster.

Props are like a direct drive system for your motor. They have to perform in a wide range of throttle settings and it is comparable to only having one gear in your car so you have to choose a good compromise between great acceleration (low gearing) and top speed (tall gearing).

I recommend that you use your boat for a while, if recently purchased and once familiar with the beast you can then make a better decision as to what suits your setup.

This link will give you a great understanding of how it all works:

Mercury Propellers

[BLACK SWAN]

Shane,

Which motor are you looking at ?
Good advise about using the boat for a bit before
up specing the prop, if the motor comes with a prop.
I'm going through the same thing myself and will know
more by end of next week.
Send me your number if you want to talk , I've got a
4m hornet .


Cheers Gary.

[Brad Y]

Shane if your talking about the boat I saw you cruising in the other day, I would be looking for a high cup 3 blade prop that will get you as close to your max recommended rpm. It will be the best combination of speed and handling you will get.

As for the holeshot idea, you have ample horses on the back to get you onto the plane. To put it bluntly and I dont mean this as a criticism as the boat looked absolutely fantastic, that hull isnt really a speed hull. Yes they go fast but you would expect that with the size motor it had. So a three blade prop will probably be the one that gets you the most speed. Having cupping on it will make it hang on to the water better in fast turns and will also enable you to run it slightly higher thus reducing drag and allowing more speed.

When you think about it really, walpole, augusta and to some extent albany and perth are the arenas where we can go WOT. Mandurah you are probably better investing in a 4 blade prop to get better low end performance. In all the others especially open water like walpole where you can fly everywhere a three blader will allow your speed to increase. So that would make it a 3 blade speed prop and maybe a 4 blade ally prop for better low end performance or going out in the ocean. This is the option im going to take.

Now saying all this.... I have found on my boat that a 13 pitch ally four blader with cupping to get the boat faster than a 3 blade 14 pitch ally. Though the 3 blader didnt have any cupping. But the 4 blades also helps in the take offs and now my bow barely lifts at all (unless its been pouring with rain and theres water in the bilge) I actually can run up to an inch of the prop tip out of the water and I have the burn marks on the prop to prove it. Im now going for a 3 blade stainless cupped prop as my speed prop and will be keeping the ally 4 bladers for mandurah and if I go out in the ocean.


Lastly I cant emphasise enough, you dont need a fast boat to catch bream... Look at lukes explorer compared to drors trophy or my tracker. Yes its nice going fast and its fun too, but you still have to be able to find the fish in the first place. I also found when I got my tracker, I was sidetracked about how fast i could go and didnt think about fishing.

Just a few things to think about. Make sure any testing you do, is done under a full tournament load.

Cheers

[donk]

gday all
just reading your reply brad y to shanes question on props ive got a good idea on what boat shanes got, as you said its not a fast hull but with a motor of that size will make it go fast, so does that not make it a fast hull.sorry to get off the subject but what makes a fast hull

onya donk

[Brad Y]

What I said was that you would expect a motor that size to make it a fast boat. And it definitely wasnt sluggish.

From what I remember shane said it was going around or a bit above 80km/hr. Thats quick for sure taking into account its ally, but another hull I know of that is ally as well with the same size motor should get around 100km/hr according to their website data.

It seems that the hull shape itself has alot to do with it. Im sure you would agree that a sleeker hull like a bass or ski boat would be a faster hull than v nose, runabout or rubber ducky style hull if they all had the same motor.

All I know is that I couldnt catch him but his outboard was numerous times larger than mine though.

[BLACK SWAN]

Shane,

This is killing me.
I'm thinking your've got a 385 Explorer so WHAT"S
on the back?

Cheers Gary.

[Rossco32]

I, Like Brad went the 4 blade Solas route....But I have two props a 19" and a 23".

The 19" I use in tourny's because chugging along at 8 knots with 2 angler's and full live wells with the 23" sees my donk drink fuel like a sick chev v8, the engine is working hard out of it's proper power band/ rev range.

Tourny loaded with the 19 still gives me 38 knots which is plenty fast enough.

I use the 23" for lightly loaded running around/ hooning / social fishing, it gives me a light load top speed of 44 knots...But off the plane it just sucks.......

I'd prop your boat to be running at optimum rpm with your intended regular load (2 people, full wells and tackle).

3 blade if you plan to run the prop deep / go off shore or 4 blade if you want to raise it higher and get into surface piercing for added bow lift.

The difference between running the four blade sub-surface V's surface piercing is 11 knots on my hull.......Quite a large difference! not to mention interesting errosion marks on the prop blades!

Like Brad said you don't need a fast boat to catch fish and there are very few areas where a fast boat makes all the difference to a good result in W.a.

A fast boat is fun but there's always going to be the increased risk of an incident/accident at higher speeds...I.e chine walk getting out of hand or Gin Palace wake catching you out....

Also.....If your non boater is going grey........it's probably best to back off a few notches!!!

Anywho here's a link to an online prop calculator (speed is given in mph) : http://www.go-fast.com/Prop_Slip_Calculator.htm

I came up with 44 mph (70 kmph ) for the 19" @ 5500 rpm (10% slip)which is spot on for my rig.

[Stu_000]

Originally Posted by BLACK SWAN

Shane,

This is killing me.
I'm thinking your've got a 385 Explorer so WHAT"S
on the back?

Cheers Gary.

Gary

He's upsized a bit......

Here's his new rig http://www.breammaster.com/forum/sho...470#post173470

Cheers

[Doc_Hollywood]

Shane,
The best advice I could give you is ask the guys at just propellors. Rod P and I took a stack of props down to belmont ski area once i put the jacking plate on to make sure the pro strike was properly proped. The guy at just props, had already told us that you will get x amount of revs out of each prop on that style of boat, this one will get you up, this one will get you fast, and this particular one is the one you will pick. As much as we tried to prove him wrong, he was exact to within 100rpm of everything he said and we ended up with the prop that he said we would take hands down.

Rossco's quote "Like Brad said you don't need a fast boat to catch fish and there are very few areas where a fast boat makes all the difference to a good result in W.a." We all know that is true because even in comps it only takes a minute or two before you are being dropped in on or even literally anchored next to.

[Shane]

WOO!!! another prop Q

I had a quick chat with the just props guy and he told me a few things to look at stats wise before looking at new props. My motor is 5000-6000 rpm optimal range. So I gather that at top speed it revs at 6300 that I need a bigger prop? Just want to get it straight in my head before asking $'s