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deerfield
12-03-2010, 12:11 PM
How hard would it be to put a turbo charger on the 325 engine? What would be involved? Any modification required or straight bolt on application? How much might it cost? Any downside to adding boost to an engine? Would the additional horsepower result in additional top end speed?

Saw on another thread that you race cars and figure you might know something about this. - Deerfield

sandm
12-03-2010, 12:30 PM
edit-you're talking boat engines.. duh....


personally, I would not even talk turbo on a boat engine in the enclosed compartment it sits in. turbo's generate a TON of heat and with nowhere to place an intercooler with sufficient airflow, you will be inviting trouble with both overheating and reliability issues imo. a single turbo would need quite a bit of exhaust piping added, reprogrammed ecu, larger injectors and airflow to feed the turbo. keep in mind that most turbos need 2500-3000rpm's to "spin up" and start producing hp. most wakeboats run out over 4k. I would also think the added shock to the tranny/vdrive once a turbo spools up would not be good for their life expectancy.

a centrifugial supercharger would be a different way to go, as they can sometimes make power across a larger rpm range, meaning more power down low where you want it, don't generate the heat a turbo does, usually run a lower psi meaning potentially less bolt-on's needed and lower chance for detonation(death to a motor), and can be added to a smallblock engine in 4-5hrs.

I don't know much about superchargers other than that, but I would not even walk down the turbo path if it was my boat.. the performance boat guys run a lot of blown boats, but they have engines with super-low compression designed for high-hp applications and have engines designed to run a much higher rpm than ours, and in most cases you are spending most of your day in the low-mid rpm band of your engine where a blown boat wouldn't want to run :)

interesting question.. reasoning?

bzubke1
12-03-2010, 01:20 PM
Turbo or really any type of performance upgrade is in my opinion not a good idea for a boat like ours. I know from experience with cars that once you start messing with the internals of the engine or boost it makes things less reliable that it was in stock form.

On a side note it would be pretty awesome to get an old direct drive ski boat and do something like this. I want to someday get an old ski nautique 2001 or 80's supra sunsport and put a cummins 12 valve in it if its even possible.

gonracn
12-03-2010, 01:23 PM
They have taken the words right out of my mouth.....

kaneboats
12-03-2010, 02:57 PM
I've skied behind a 25 HP outboard on a wooden boat (it has been a few years though). It kills me when you guys think 310-325 isn't enough on a boat that's probably lighter than that old wooden one was.

maxpower220
12-03-2010, 03:17 PM
Turbos are fun, especially if you can build an engine to handle 25-30 psi of boost. However, it takes a lot of plumbing of hoses, space and cooling for an intercooler, and the venting of heat. Not really a good place to do it on a boat. Also, the function of the boat's engine also isn't well used for a turbo application when compared to supercharging.

Modern supercharger do a similar act as the turbo, but usually can be done in a smaller area. Also, the power response would be a little better in a tow boat application. In a drag boat, turbo all the way.

Either a turbo or a SC could be added safely to a 325 with about 3-5 psi of boost with no internal mods. However, you will need to alter the timing and fuel management to deal with the boost. Why not look at a new MasterCraft with an Ilmor engine?

sandm
12-03-2010, 03:21 PM
how about a 100shot of nawssss. just about the time that skier yells "hit it" and you really do :)

deerfield
12-03-2010, 04:19 PM
I've skied behind a 25 HP outboard on a wooden boat (it has been a few years though). It kills me when you guys think 310-325 isn't enough on a boat that's probably lighter than that old wooden one was.

kane - I agree. A 325 in my Outback is plenty. As with your experience, my pop taught me to ski behind his Starcraft fishing boat with an 18 hp Johnson. Here's where I'm coming from. I was thinking about things that I could do to my boat. But eveyrthing I thought of I can pretty much eliminate cause someone has already done it (e.g. audio and wraps) and I really pretty much like my Outback just the way it is. So why spend the money. Even the swim paltform has the original black traction pad from the factory. Works fine. Then I got to thinking that from time to time I take my boat out on Lake Michigan where there is flat water for miles (on the right day) or find myself in the vicinity of a guy with a fast boat, and what it would be like to flip a switch and be able to go like the wind, hit 60 or 70 MPH. I think it would be cool to have a "sleeper" boat. It's not something that I've heard any Moomba or Supra owneer yet do to his boat. But, having read the above from people who know about turbo and super charging, I guess there is a good reason why. I remember riding with a guy in his off shore boat and loved the speed and sound of the engines. - Deerfield

maxpower220
12-03-2010, 06:03 PM
Regardless of what you do to the engine, your enemy will be the hull. All hulls are built for a function, ours are built for a wake at 36 mph. Most Outbacks are topping out at @45 mph (give or take 1-2 mph). As speed increases, so does the friction on the hull (per the way it is designed). Check the Nautique forums for speed issues. Trying to break 55mph in an Outback would probably require more than a turbo and may be nearly impossible.

Even the Python (496/502 cid) motors used by CC in 196 were only in the low to mid 50s.

lsvboombox
12-03-2010, 07:39 PM
I wonder what this wake boat tops out at? its got twin turbos on a lexus v8... 550hp

http://www.luxmarine.com.au/Wake_Ski_Boat/2153_Extreme_Ski_Boats_X-Factor_V-Drive.php

sandm
12-03-2010, 09:20 PM
HATE to see the heat in that engine compartment..

never forget getting my old evo dyon'ed and at 31psi and full throttle, after 2-3 runs the ex manifold and turbo housing were glowing red hot. was cool.....

viking
12-04-2010, 12:05 AM
My dad's cousin had an Eliminator Jet boat with a Blown 454. This was about 20-25 Years ago but I remember it being the fastest boat on the lake North of the Twin Cities. You could see the fishtail and hear the roar from a few miles across the lake and you knew exactly who's boat it was :)

I loved that thing! This was before wakeboarding really took hold and we skied, kneeboarded and tubed behind it all the time. Was nothing like going wide open though.......and it had a billet foot for a gas pedal :D

kaneboats
12-05-2010, 04:28 PM
Man, I hate a gas pedal in a boat. The thing jumps up and down and you can't keep your foot still. Skiing behind my uncle's jet was the worst. He's missing a few toes and can barely hold a car's gas pedal steady. There's a good reason for hand controls in a boat.

lsvboombox
12-05-2010, 07:59 PM
I got a hotfoot in my bassboat which does about 75 and love it for bass boats... Couldnt imagine pulling someone all day with a hotfoot though... your leg would be in extreme pain by the end of day(if not by noon)........

Mikey
12-06-2010, 09:20 PM
Turbo i don't think is the way to go,but Supercharging is getting more popular. As someone above mentioned MC and ilmor now have a SC option available.As we were told at a recent customer appreciation night we attended coming straight from the owner of Ilmor motors. They had an x25 done up with a Sc putting out aprox 600hp.
I've heard of Jumpers doing this to there personal boats as well. Ryan Dodd and rumour Freddie Kruger as well.
Ryan Dodd was at this show i went to but i missed my chance to talk to him.

sandm
12-07-2010, 07:48 AM
I totally get doing this in a car, and in my last 3 turbo'ed 4bangers, I modded extensively in a never-ending quest for faster 1/4 mile times, but with the limited research and knowledge I have on boats, seems that for MOST wakeboarding applications, a different prop makes more sense than any engine upgrade would, and don't know about anyone else, but my top speed only really needs to be over 30, as that covers any wakeboard speed comfortably and I'm not ever in a hurry to get anywhere when on the lake.. heck, I don't have cell service at the lake and don't even begin to miss it :)

DOCDRS
12-07-2010, 08:00 AM
Regardless of what you do to the engine, your enemy will be the hull. All hulls are built for a function, ours are built for a wake at 36 mph. Most Outbacks are topping out at @45 mph (give or take 1-2 mph). As speed increases, so does the friction on the hull (per the way it is designed). Check the Nautique forums for speed issues. Trying to break 55mph in an Outback would probably require more than a turbo and may be nearly impossible.

Even the Python (496/502 cid) motors used by CC in 196 were only in the low to mid 50s.


Mastercraft put a supercharger on Champ barefooter Keith StOnge's 8.1 litre Mastercraft...........needless to say after clamshell mod to accommodate the blower, then cover the intake as the noise was deadening, the boat got at least an increase of at least a Whopping 2mph......It was however able to consume gas faster than you could fill it up, and would over heat and shut down after about 10 - 12 mins of wot........practicing barefoot endurance at 50 mph.......but it sure did look cool