Need More Speed! (496Ho Content)
 

Hey there,
I'm new to the forum and I have tried to do some hunting around with search on my own to find some answers, but I looking for peoples thoughts as many of you see very knowledgeable.

I don't have what you would traditionally call a "Go-Fast" boat, but I am hopeful that you guys can still help me out. Its a Riviera M470 with twin 496 Mag HO's. This past winter I went ahead and put Dana Marine's Thru-hull exhaust on her and figured I would see how the season went. I didnt see any real gains (just great noise!) so I am currently re-examining the props (still stock). But ultimately, I dont think props can possibly get me where I want to be (I currently top out 45-47 but want to be 55+).
This leaves me with either going for a Raylar kit that boosts me up to 525 or so, or going with a Whipple supercharger. Going with the whipple means I will have to swap my drives for something else (any suggestions?), but its something I would look into.

Thanks for any help guys!
Oh here is a pic of the boat:
http://i47.photobucket.com/albums/f1...IMG_0250_2.jpg
http://i47.photobucket.com/albums/f1...IMG_0239_2.jpg
http://i47.photobucket.com/albums/f1...IMG_0958_2.jpg
this is apparently the best pic of the headers I have :rolleyes:
http://i47.photobucket.com/albums/f1...1/IMG_0963.jpg

My biggest concern with the supercharger is there may not be enough airflow in the engine bay and temps will get too high....

Thanks again

Beautiful Boat !!

At what RPM is your top speed currently?. ie. how fast are the motors spinning?

Having asked that... I will tell you that I am a Whipple fan.

Since having a Whipple motor, I will never go any other route.
Power is fantastic, and Dustin Whipple has got to be the most helpful guy on the planet when it comes to boat motor setup.

1 vote for Whipple

Chris

I would also go with whipple,,and some low boost so u can leave the drives !!! I would not change them ,,just the props ofcorse.
If ugo with a max of maybe 600-620 HP u bee fine ,just take it easy when uget on plane and throttle right if u would fly ,,which probably is not gonna be that much with this NICE excalibur.

:ernaehrung004:

Thanks! Its a great boat, we have a blast with her!

Currently the max rpm seen is 5000 to 5200 or just under. I know thats a bit to high for her and she should be around 49-5000 range which i believe is a sign the props need to go.

The drives I believe are only rated to 450....so 600 is waaay out there for them no? lol

Another concern I have is that I could get new props for this season, but if I am doing Whipple for the new season, wont I just have to do new props again? That kinda wastes the money im throwing at the props for this year...is it worth it?

Don't get new props until after you do your HP upgrades. Your current props will give good baseline numbers, and help estimate what final size/ gear ratio will be best. Are you currently using the 2.0/1 gears?

Carder

Also ,,we call this boat a CONDO not a go fast !!! LOL
Like u said ,,waist of money with the props.
But i have seen regular bravos on 600 HP and the bravo 3 is basicly the same exept the lower and u need that lower to move that big boat.
i would do the HP and then see what it does ,,if u stay easy on the exelaration and don't fy to much ,,,should be fine,,,its the tourqe what kills drives not the HP !!!!!!

it's going to take some serious H/P to get a big boat like that to that speed, I think you are going to be sorry with reliability with your currant engines....big diesels are the way to go in something like that trying to run that fast...my .02....Rob

Haha....thanks.


I thought one of the biggest pro's to the whipple supercharger was that they are hugely reliable, ect? Like OEM ect? I know that going FI isnt going to be easy and that I will have issues, but I wonder unreliable the system will be?

I agree some big power will be needed, so I am looking at alternatives other then replacing the engines. Would you suggest I look at other options then whipple?

I have gotten up to 47 with the boat stock (i.e. No thru hull exhaust), so moving up to 55 shouldn't be terrible I would have thought. 50 is the minimum goal for the boat really...but 55+ would be welcome :-)
That said, I wouldn't think it would too hard to hit these goals?

How much does the boat weigh?

Chris