Looking for performance increase in 454 magnum EFI and prop advice.
 

I have a 1996 Cougar Sport Skier, 20.5 454 magnum efi , in like new shape , currently running 25 tempest 3 plade , boat runs 73.6 On GPS , trying to decide what is the best way to go for more performance, looking for possible a m1 or m3 procharger kit to bolt on if I can find one , and running low boost to keep it safer , also is there a better prop I could possibly try for the time being other then this 25 tempest? I was running a 23 mirage plus 3 blade and it made 72 on gps. Any advice would be great.

Thanks
Daniel

Whipple or procharger setup would get it done

So would that entail reprogramming the ECU if he adds a ProCharger? What about injectors?

What does the boat have for a drive - Bravo? External or internal steering? Is it pretty stable at 72 MPH? Adding an additional 6-10 MPH might push a 20 foot boat over the edge and make it a handful to drive. I don't know much about that make of boat - maybe it's a deep V and very stable like the Donzi Classic.

Yes boat is very solid and safe at those speeds bravo one leg I'll post pictures, if you look up cougar sport skier 20.5 you will see the boat , it's a bow rider , very nice well made boat

I am kinda in agreement with budman. You push that hull up to 80 and bad things can happen very quickly.

if the boat runs 73.6 mph you should be a happy camper.unless you are willing to spend a lot of money leave it alone and go boating.

Theres a guy that procharged his was running low 80's on gps and was totally fine , hull was stable just like it was in the 70's

$1000 per mph. 7mph = $7000

daniel475 - Mike Tkach alter ego just typed that. He has two 1000+hp engines with #6 outdrives....obviously he can't leave things stock. LOL.

You are in a position to thinks about upgrades in many different ways.

#1) very worthy of consideration - pull motor, wrap it, and put it in the corner. Build another motor. If you need a back up, you have a good one. Sell the boat ? Be worth the same with stock EFI big block power.

#2) Those superchargers are good, but there are mods to be done outside of just bolting it on. Headgaskets/ head bolts / programming /injectors / etc. Talk to Eddie Young or the like. They have done many and can tell you what else is needed vs just what ATI givers you and says to do. Young is also very involved with Whipple installs so ask about that.

#3 ) Cam / head work / exhaust / etc on present motor and obviously will need tuning (live tuning is always recommended if not mandatory) will work pretty good since your boat responds well to the HP it already has.

You should sit down and add up the different options. $$$ and positives/negatives.

As with any performance mods with boats/cars/bikes/sleds/ etc,etc - always expect much more $$$ involved then your originally planned.

Thanks for the advice, and I know how it goes if you bank on 5000 it always end up being 10000 , don't plan on getting rid of the boat anytime soon , just was looking for some more hp , I will for sure get in touch with those guys , thanks a lot

Heres some videos of one that was supercharged, also obviously should change out stock exhaust, what would be a good set of exhaust for this thing , but I could also keep the silent choice option that it currently has .

https://www.youtube.com/watch?v=cvw_oFA2gQg
https://www.youtube.com/watch?v=8JRG0bvHYaI

Looks like you have been pondering this for a while. ;)

http://www.offshoreonly.com/forums/g...ing-about.html

Looks like a fun little boat. However, since it is set up as an all-around family ski type boat, it probably has a fairly flat bottom on it (probably 20-22* deadrise), which means it will ride over the top of wakes rather than slice through them like a 24* bottom would do. I would be worried about it getting major air and becoming unstable at really high speeds, especially if you encountered some sizable wakes. You are obviously more familiar with the boat than I am, but I do know that sometimes the safe limit comes up without much warning, and you can find yourself in a world of trouble in the blink of an eye.

http://www.powerboatlistings.com/view/6322

Don't forget about your drive upgrade, if its in good shape and not broke now...it will be. Talk to thirdchildhood, he put a 525EFI in his Donzi 22 and it runs out well, no supercharger to mess with.

m1..

Have you tried a 4-blade prop on it? Light hulls with a high X-dimension often respond well to those props.

You need to talk to a marine engine builder with a lot of experience with superchargers. Guys like Eddie Young, MER, Haxby would be good sources to make you aware of what you will need to do to get your 454 to live with a supercharger. There's a lot more to it than just slapping one on. You might get by with that for a little while, but eventually you will blow something up if not set up right.

You might find more experience with that hull over on ScreamandFly.com. They cater to the smaller jet and ski boat hulls. OSO has more guys with experience with the bigger hulls, although there is a lot of crossover here.

ya I have for sure , this is my boat [IMG]10467001_10152250539257477_8725703498198264364_o[/IMG], that didn't work how do you post pics, been trying to get in touch with Haxby busy guy

pay the man $$$$$ to post, or post a link to a hosting site

I use photobucket.

http://sherwoodpark.boatverse.com/po...kier_1703.html , heres a link to my boat , little bit nicer then the one posted above lol