Free horsepower?

My main question is, has anyone thought of trying to squeeze some extra ponies (and or torque) out of their boat motor?

I was just looking through my newer Summit catalog and it struck me odd that I have not heard of anyone swapping out their regular pulley driven waterpump for an electric version; or even mention it. This a pretty common "mod" on a lot of street driven hi-po cars. It was notoriously common on the Camaro and Trans Am LT-1 engine due to the stupid optispark. And these electric waterpumps usually last a decent amount of time, and have successfully been used on daily driven street rigs.

With gas prices rising and the amount of weight we put into these boats to create the biggest wake possible; has anyone thought of freeing up some horsepower? I was thinking about the physics of it and the trade offs. I was trying to think through the whole "energy cannot be created nor destroyed" but it would not suprise me if someone could pick up a couple of extra horses that were being lost through parasitic drag and the like.

Any thoughts, comments or ideas? I am just kind of throwing this out there for other wrench heads to think about as well. Modifications that are commonly done on street cars that could carry over to the water. Ram Air, under-driving crank pulleys, lighter flywheels/flex plates, necking up or down exhaust diameter for torque or horsepower, torque based camshafts, etc.

Making more power is easy enough. I think you would just go beyond the capability of the prop so then you would need to change prop and probably lose some pulling power down low.

Car engines and boat engines have different demands so performance gains are from different sources. There are lots of applications that will increase Hp on a boat very effectively. In particular are super and turbocharging. You could also use a nitrous oxide kit to give much improved hole shots but generally that creates other problems and the nitrous is expensive, not to mention the extra fuel you burn.
Electric water pumps are good for drag race applications where you are stock piling the power to run the water pump in a battery and saving the power for a quick blast. You can then recover the inadequate cooling after the run. On a boat it would not help because you use too much power for too long. Light weight rotating parts give you improved acceleration but it matters most on fast revving engines and a boat without gears doesn't get as much gain. Playing with the exhaust and intake will help and is done. Look at the Hammerhead exhaust manifold or the Black Scorpion intake as a couple of obvious examples. Ram air would help but not if you are going less than 30 MPH.
Basically, anything you can do to a car you can do to a boat. The biggest gains from a car for performance are always from lightening the vehicle. Unfortunately that's the opposite to what you do with a wake boat.
What you need to do is start with no ballast and fill the ballast as soon as you get to wake speed. That would require some impressive pumping capacity.
Like SVB says, you eventually get limited by the prop's ability to push water but there are lots of ways to solve that. Eventually It's just a question of money and you'll find that the engines we run in newer boats are pretty good compromises for economy, expense, and power.
I think someone needs to look at a good screw type supercharger with a pod drive to make the next step in wake or ski boat performance.

(Message edited by rallyart on April 06, 2007)

Art - I would say that the industry is much closer to turbo charging with the onset of the CAT. When you look at the 07 INDMAR design, providing a watercooled CAT I think is a hudge stepping stone. With the heavy loads we carry, the turbo makes alot of sence.

I would think that coming up with some sort of CAI would give you the most bang for your buck. I'd imagine that having the engine draw in cool outside air instead of the heat soaked air from the engine compartment would do a lot. However, you'd have to have the guts to cut a significant hole somewhere and engineer some plumbing to keep up with the engine's demands.

why don't we see more engines with camshaft mods? seems like a pretty easy way to increase hp and torque, without brining in all the problems of air induction and super/turbo charging.

Has anyone fitted a K&N filter to their boat yet? It would help with throttle response and use a little less gas.

Nacho- I think we all ready do see that. Many of the makers have different versions with different camshafts to help increase HP and torque. I know marine power in the Tige has the 315 HP, and the 340 HP and then goes to 360 HP all with the same block. The difference is the type of cam they are useing coupled with some other mods to generate more HP. Anyone can bore the block and start to generate more HP but overall this is not practical in a wakeboat. The Hull design is the biggest limiting factor.

Horsepower is not what we need more of... Torque is what wakeboats need. That is what gets us out of the hole with 2000lbs extra on board.

I wonder why we don't see more diesels in wakeboats? They would add weight, have a ton of TQ, and pretty soon, gas will be a lot more expensive than diesel.

Just remove the water pump altogether & go with a crossover - problem solved.

You can run a cold air intake from the high pressure area in front of the windscreen and pipe the air under the floor or under the gunwale to the engine intake directly. The boats already put cold air through there to cool the engine compartment.
The horsepower increase is only the difference in the air density from the two sources so it's not going to be very noticeable, but every bit helps. A K&N filter can make a difference over a regular air filter, and streaming the air more smoothly to the throttle will help. You can run the K&N with out the oil also. It doesn't filter the small stuff as well but it is still better than a normal flame arrestor for filtration.

I agree with coach on the camshaft deal. I have ridden in the hammerhead as well as monsoon powered wakesetters and noticed a significant increase in "lope-ing" due to the camshaft.

Big D, I agree, and I believe that decreasing the diameter of the exhaust increases backpressure increasing torque; but I could be wrong. Which brings up another question: Why do these boats have 4" exhaust tubes while even the highest horsepower cars can effectively run well with dual 3" exhaust? Oops, that might be due to the extra space the water cooling takes up, huh?

A regular K&N filter will not do. However, K&N does make USCG approved flame arrestors (available at summit racing). I replaced the small metal flame arrestor on my carb with a larger K&N one and i gained abour 200-300 rpms and a little better throttle response to boot. At the very least, cleaning the stock flame arrestor should net you some gain.

I tried to get a K&N for my 350 Mag and couldn't. They won't even make them. They did for a short while, but it was such an increase in air that it was creating a HUGE lean condition that the fuel system could not overcome.

I also had a plan to plumb some more air into the motor box using some inline blowers from the air inlets at the bottom of the windshield to the motor box. Got talked out of it by some very knowledgeable Merc mechanics. Once again I ended up at the "these motors are pretty tuned to their environment as it is" conclusion. With out doing a lot of work to several areas, you're just not going to get much more than you already have.

We found a great solution to saving gas though, we surf. All the fun, none of the pain and easy on gas.

We also went to a 13 x 11 1/2 .06 Acme. Helped a ton.

(Message edited by Nickypoo on April 06, 2007)

K&N flame arrestors at summit racing http://store.summitracing.com/egnsearch.asp?N=700+4294925239+400171+115+42948425 21

Matt:

I would advise against the idea of an electric water pump. The situation that you described for a car is completely different. On a car, the cooling water is circulated, the pump really doesn't do much work as it doesn't have to lift the water. The raw water pump on your boat has to be able to lift water and thus it has to do a lot more work.

Next time you are changing the belts on your boat's engine, run this quick test. With all the belts off, give the circulating pump a spin by hand (it will be the pulley right above the main crankshaft. Spins pretty easy, doesn't it? Now give the raw water pump a spin. What, you needed two hands?

Let's face it, if you are talking about any significant amount of horsepower gain then a fraction of a horsepower is nothing. Now, go find a 1 Hp 12 volt motor.

Even if you found one, a one horsepower motor still needs one horsepower of energy. That will burn ~750 watts. At 12 volts, that is 62 amps. that is the entire output of your stock alternator.

The people that I know who were into street racers would do things like that except they relied on their battery to provide the power when they needed everything they could get from the engine. Most had a switch on the dash that would turn the altnernator off. Some would stop, slip the belt off the alternator before they raced. A few didn't even have an alternator, they relied on being home before the battery went dead.

I don't think that you want to play those games on a wakeboard boat. Heck, most of us are going the other way, trying to get more juice from the alternator to keep our stereo going.

If your concern is about gas prices then increasing horsepower is the wrong thing to do! You need to work out ways of doing the same job with less power. Wedge plates instead of ballast comes to mind.

If you do want more horsepower, the best approach is more cubic inches. If you can't do that, the second best is turbo charging.

Keep in mind that there really isn't any free horsepower. If it was free and easy the manufacturer would have done it to start with.

Rod, I agree with most of your comments aside from this one...

"Keep in mind that there really isn't any free horsepower. If it was free and easy the manufacturer would have done it to start with."

Only becuase there is a cost benefit calculation done by the manufacturers. If it doesnt add any value to the vehicle, I doubt they would do it.. for instance Hi-flow catalytic converters, cut outs etc. My uncle races circle track and reiprocating mass is HUGE to those high reving engines. Lighter drive shafts, rocker arms, and any other rotating mass can make a gigantic difference in wheel speed and power as a result. I believe the general term is that 20% of an engines power is lost through the drive train.

I do agree about your mention of the raw water pump taking a lot of power; I think I mispoke or the boat/car language got in the way. I meant the circulating pump on the boat (a water pump on the car). There have been enough dyno tests to prove that an electric water pump on a car increases power, and they are pretty common in the street racing scene (daily driven pavement pounders).

I dunno, just brainstorming and thinking of ways to help in everyones quest to get on plane quickly and not have to re-fill twice a day, lol. I intended this thread more as a brainstorming discussion than a "help me get more power".

Any other ideas? I would be curious to see a real world test, taking a stock monsoon 340 to a shop and having them install some of these ideas similar to what the mags do. Show a stock baseline dyno, after the mods, and total gas consumption.

A nice set of Hi-Tek exhaust manifolds will help. stainless steel, one piece, like headers on a boat motor, pricey though.

(Message edited by 95sn on April 06, 2007)

Matt let me know what you come up with when you do all those installs.