Hole Shot Help...

[nofearengineer]

Hey guys,

As you may know, I drive a 2005 Tracker Avalanche...it's an 18.5' aluminum hull, with an Optimax 115 on it.

I use a 13.25 x 20 3-blade stainless Laser II prop.

I max out at 45 mph at 5800 rpm.

The motor is rated for 5750 rpm, so I think I must be pretty close to right.

I use an SE Sport 300 hydrofoil on it, so you'd figure it would have a reasonable hole shot... nothing amazing, but reasonable.

However, I just can't seem to get the thing to plane out very fast. Sometimes it seems like it takes me 10+ seconds to get up on plane. I trim it way down like I'm supposed to do and slam the throttle down, but it's still a dog.

I rode with Woody this past weekend in his Skeeter, which has a 150 VMax, and the thing was just ridiculously strong, even with both of us in the boat. I know he's got more ponies under the cowling, but his boat was planing out in just a hair over 3 seconds, fully loaded. (I may have to change my handle to "crylikealittlegirlengineer" after our runs across the lake though , Woody is one bassboat-drivin' dude, let me tell ya!)

For now, I'm pretty content to "putter around" below 50 mph (maybe 60 for a dawn run across a glassy lake), but I'd like a bit faster take-off, I guess. I would love in two years to buy a 175 Optimax (what the boat is rated for) and learn how to drive it really well, but I'm still interested in getting everything out of what I have now. I love just about everything else about the boat.

Are these slow hole shots just a symptom of too small motor? Or could I have a problem with my hull? Anways, I know there are a lot of experienced guys on here, and I value your opinions.

[zooker]

i would borrow a 4 blade ss prop around a 19-21p and see what happens..


that thing is tin???? hell i thought it was glass..


zooker

[nofearengineer]

Thanks, Zook. I may try that before Fall gets here. I need a spare prop anyway.

Yep...she's pretty slick for an aluminum boat, eh?

I'm not even sure I can get a kicker motor to mount on my narrow transom. I've got those rounded "pillow" back corners. I wonder if someone makes a mount where it bolts to your transom, and then kind of kicks out to port a few inches to make more clearance for the main outboard. Ever see or hear of one?

[bonsaibp]

You may want to check how the weight is distributed . Too much weight up front will make it harder and longer to get on plane.

[nofearengineer]

Bonsai...more weight in the front helps planing out, not the other way around. Frankly, I've thought about adding some weight in the bow to improve handling in chop. Funny thing is...the only stuff I have in the rear of the boat is my three batteries and my fat arse. But like I said, Woody's boat threw both of across the lake like a rocket.

Maybe I'll run her lower on fuel and see how much it improves the takeoffs. If that's the case, I might try another 100 lbs of weight in the port bow and see what happens.

[BigBassin144]

Originally Posted by zooker

i would borrow a 4 blade ss prop around a 19-21p and see what happens..


that thing is tin???? hell i thought it was glass..


zooker

Damn, I though it was a glass boat too... nice looking alminum boat.

BB

[bonsaibp]

Originally Posted by nofearengineer

Bonsai...more weight in the front helps planing out, not the other way around. Frankly, I've thought about adding some weight in the bow to improve handling in chop. Funny thing is...the only stuff I have in the rear of the boat is my three batteries and my fat arse. But like I said, Woody's boat threw both of across the lake like a rocket.

Maybe I'll run her lower on fuel and see how much it improves the takeoffs. If that's the case, I might try another 100 lbs of weight in the port bow and see what happens.

I was told 20+ years ago when i got my first boat to place the heavier tackle etc in the back to make it easier to get on plane. I'd like some other experienced boaters to add their opinions. I'll be pissed if I've been doing it wrong all these years

[MississippiBoy]

Think about it this way...when you're sitting still and punch the throttle, what happens? The nose of the boat rises, then as the boat planes out, it settles back down. So, the quicker you can get the boat's nose back down, the quicker it'll get up on plane. Transfer the weight to the front to keep the nose down to begin with for a better hole shot.

I know that in my little 14' boat, it makes a HUGE difference when there's somebody sitting beside me in the back versus the front seat. If me and my 300 lbs buddy are in the back, I just about can't get it to plane out. If he goes to the front, it's quicker getting on plane than it is when I'm by myself.

[bonsaibp]

My bad . More weight in back will slow your holeshot but it will improve hull lift and proper running attitude.
So for better holeshot don't put weight in back but for overall better running and handling you should.

[nofearengineer]

Hey...I just got back from my local Merc dealer, and he gave me some interesting information. He said that for one thing, Laser props are not really known for being a great hole shot prop...they're more of a top speed kind of prop.

That being said, he still thought there might be something wrong with my particular setup, given the slow plane times I'm talking about.

He thinks there might be a problem with the exhaust holes in the side of my prop...as in not letting enough exhaust out into the blades during launch, which would make my motor kind of bog down, turning against all water, instead of a water/gas mixture. My motor runs fine, but come to think of it, it does not ramp up rpms really fast when I slam the throttle at launch.

When you guys hit your throttle at launch, what percentage of your WOT rpms does your motor jump to right off the bat? I think mine is only going to 2200-2500 or so, and from there it makes the slow climb upwards to 5800 at max speed. Does that sound right?

If this is the problem, the fix might be super easy and cheap...get bigger-hole inserts to go in the exhaust holes.

[zooker]

sounds right try it with no inserts in it once just to see if thats the problem...

zooker

[bassboogieman]

Are these slow hole shots just a symptom of too small motor?

I think you answered you own question. You didn't mention if you have a jackplate, that may help if your motor is too low on the transom. That combo could probalby get by with a 3" J/p but check with your dealer as you may be able to run one a little bigger. Depending where your motor sits on the transom, you might want to talk to your dealer about raising it, should you not have a jackplate.
The most load on you outboard will be getting the boat up on plane, once on plane the smaller outboard will move you along fine. An 18' boat as wide as the Avalanche is a lot of boat to get up on plane, two people, gear and gas add significant weight for the 115HP to get moving. I haven't seen too many of the Avalances, none with a 115HP, the few I've seen have the 150HP, which based on the boats size should be the standard motor. If you have a prop with PVC plugs you can try changing the sizes, but I don't think it will greatly improve your take off. A 4-blade prop might give you a bit more on take off, at the cost of 2 - 3 MPH on the top end. Normally you'll drop one prop size when going from a 3 to a 4-blade, so something like a 19" Trophy Plus (has the PVC plugs) would be a starting point.
A full throttle straight forward take off would be a lot of load for the 115HP. You can try improving your take off by steering hard left and getting the boat moving, hammer the throttle while making a hard right turn. That will lift the starboard side of the boat intially and get some water under it, the hard right will provide additional lift. Just make sure there isn't anyone behind you when you try it. The left - right is easier than a right - left, especially with cable steering as the motor's torque will help make the right turn, rather that fighting the motor's torque to turn left.

[WTL]

Nofear, I have the solution to your hole shot problem.

Its very simple. We trade boats. I take yours and you ta...well I take your boat.

Fixed. Your welcome.

[nofearengineer]

Haha, WTL. Is that a subtle hint for me to stop whining?

About that 4-blade prop. My Merc dealer kind of came down against that idea. He thinks a 4-blade might be a little too much prop for a 115hp. He typically only installs them on 135 and higher outboards. I am still open to that idea, however, and if modifying the vents doesn't help, I will look into it. I figure if he suggests selling me a $10 set of plugs instead of a $500 dollar prop, that's pretty cool.

Bad thing is, if I do decide to "try out" a prop, I will have to buy it. However, I can then return it if undamaged, if it's one he has in stock. Unfortunately, he doesn't keep many 4-blade props in stock, and if he has to order one, I can't return it. I really wish I lived near a big city sometimes.

So much for not whining anymore haha.

[wibassmaster]

I think your underpowered with a 115. If the max hp is 175 you should have atleast a 150 on it..

[nofearengineer]

Yes,

I know I am underpowered with a 115. Bass Pro Shops and Tracker Marine sold a lot of these boats underpowered to get them out the door cheap. Which is a shame, because the max rated 175hp only cost about $4000 more than the 115.

That being said, my 115 should still be getting me out of the hole better than it does. Hopefully, modifying the vents will have the same effect as putting a high stall converter on a hot rod...getting me up into a higher rpm range where I have more power.

As to the jackplate issue. Nope. I'm bolted to the transom. However, the height seems to be good, at least on paper. My cavitation plate is just above the bottom of my boat (the true bottom, not the stepped part).

Oh well, if the fishing starts sucking tomorrow in the middle of the day, I'll take her back to the ramp and start messing around with it.

[BigBassin144]

Nice one WTL. I'd trade you our boat too. It only goes 9mph and never gets on plane, so you wouldn't have to worry about it! It does accelerate from 0 to top speed quite fast though!

BB

[MarcBorger]

I would not bother putting a jackplate if you only have a 115. A guy in my club has an avalanche with a 175 with no jackplate and it moves really well. Sell the 115 and get a lightly used 175.

[nofearengineer]

Marc,

My eventual plan is to get a 175 (in 2 years probably), but like I said, for now I just want to get the most out of what I have. Plus, I really need a lot more hours in the seat before I'm ready to drive anything that can do 70+ mph. I know my limitations.

Next year is my electronics year. I'm hoping to get some better fishfinders, and some SmartCraft gauges. And if the government actually lets me keep some of my income, maybe a kicker motor too. I've had my eye on a 4-stroke Merc 9.9 that I'd like to remote steer and start, or quite possibly even get a couple more batteries to parallel and try a Minn-Kota outboard mount electric trolling motor. Either has got to be more stealthy than my big outboard.

[WTL]

Originally Posted by BigBassin144

Nice one WTL. I'd trade you our boat too. It only goes 9mph and never gets on plane, so you wouldn't have to worry about it! It does accelerate from 0 to top speed quite fast though!

BB

Hehe, I'd take that trade. Not so sure your Pop would be enamored with it. You can always upgrade the motor, I could find a 40 for that boat..

I can never find a way to make the spook handle rougher water or hold more gear. It is what it is. Actually contemplating selling her before things get too bad.

[Rebbasser]

Nofear-this may be a dumb question, but what do you do with your trim when you hammer down? I had a similar problem-slow up on the plane. Now, when I hammer down I hit the trim at the same time and trim it up. That seems to improve my planing time.

[nofearengineer]

Reb...I keep the trim all the way down until I plane out.

As a status report, I ran the boat down to 1/4 tank this past weekend, and it did perform noticeably better out of the hole. It was getting up in 6-7 seconds, which doesn't seem too bad, considering the review boat had a plane time of 2.9 seconds with a 150. That boat wasn't loaded down with gear and a giant driver, either. I think if I get a 175, it will probably be a 60-65 mph boat, even with me and all of my gear.

Mark (Woody) will be happy to know that after our version of Mr. Toad's Wild Ride on Lake Monroe, I'm hardly scared at all to run my boat through big chop at 35+ anymore.

Taking the plugs out just made the prop cavitate way too much, sitting and spinning. There is a size plug between the ones I have and totally out, but I'm not sure it will be an improvement. If I get 15 bucks burning a hole in my pocket, I'll order them and try them out.

[1FASTLASER]

Ok I have read what has been posted and here is my recommend

Yes you have to tailor the prop to your boat. The prop exhaust holes is your ticket to better holeshot NOT moving weight to the front. The exact size and which holes to plug is a trial and error thing. Moving weight to the front of the boat is NOT a wise choice. Yes it will help a little on getting on plane but you suffer WAY to much after you get on plane. Your motor is trying to lift that added weight not ony on holeshot but also after you get on plane. Balancing in a boat is important especially when trying to optimize performance.

[nofearengineer]

Fastlaser, I totally value your input, as I know you are a speed guy.

But I wanted to let you know about the Avalanche, if you've never driven one. It is a bit light in the bow anyway, being all aluminum, and bounces around quite a bit. Even with only a 115, I have plenty of trim on the motor left when I start porpoising. The motor is gonna have no problem at all holding this bow up, let me tell ya. My plan was really just to kinda make lemonade when given lemons, by helping the hole shot while fixing the handling.

If I get a 175, I would bet I could add even more weight to the front, and really get the hull slicing into the waves. Remember, this hull is not a full pad boat. I do appreciate any more comments you might have, since I'm sure you know more about hulls than I do.

[1FASTLASER]

Hmmmmmm....oklets get this puppy doing what she is supposed to do........Can ya put up some pics,,,,,need a pic of the rear of the boat at about the level of the bottom of the boat and where is your moter bolted up......those 2 pics and the info you have given already and we should eb able to get her over the hump. You do know that when a boat is porpising what actually is happening is the prop is loosing bit therefore the boat starts its dance. There are several things that can cause this......of course the prop itself is one thing then you add in either a small engine,wrong engine height etc etc and then it really gets to dancing. My tidecraft even tough it has a warmed up 90 will do it at about 1/2 to 3/4 throttle if I dont have her tucked under some. Drives me nuts but the problem is a small engine therfore a small prop and the engine height at a certain speed and wholla.......feel like I am on a trampoline. Mani difference between yours and mine is weight. I have a heavy front and you have a light front. Right off the top of my head I am thinking you need some cup in the prop to bite a little harder that will hold the bow up. The Laser prop is a "nose high" prop once you get engine height right in relation to bottom of hull.