Assuming I had a magical boat.....

You know the drill..

Moderators: Redneck_Randy, badmoonrising, lakerunner

Post Reply
Message
Author
User avatar
mgarvie
Posts: 187
Joined: Sun Jul 29, 2012 12:58 pm
Location: Pekin, IL

Assuming I had a magical boat.....

#1 Post by mgarvie » Sat Jan 12, 2019 7:46 pm

Just pondering while having a beer. I keep reading that there is a point where adding more horsepower doesn't give much more speed. Assuming I had a magical boat that could hold up any size motor the same as my little 60hp. What speed increase would my old 20 foot pontoon get with the Seven Marine 627HP outboard?

User avatar
lakerunner
Site Moderator
Posts: 4820
Joined: Fri Mar 17, 2006 2:31 pm
Location: Live in McAlester, Ok Boat on Tenkiller
Contact:

Re: Assuming I had a magical boat.....

#2 Post by lakerunner » Sat Jan 12, 2019 8:44 pm

I don't know if there is a way to measure the speed of a 620 hp ripping through the floor and your ass on the way out the front
Loyd & Betty Meeks
Livin the lake life
2004 Tracker 22 Regency/2010 90 E-Tec. Pulled by Ford 2020 F 250,
McAlester, Oklahoma
Home lake is Tenkiller

User avatar
wwind3
Posts: 1515
Joined: Tue Jan 13, 2009 10:03 am
Location: Lake Livingston Tx

Re: Assuming I had a magical boat.....

#3 Post by wwind3 » Sun Jan 13, 2019 4:52 am

dunno--but the pontoon speed record is 114 mph.. Powered by 900 hp- 3 300hp Mercs

https://www.youtube.com/watch?v=QUAJRv27r-0
2009 LOWE SS204 25in logs
90 Merc Optimax
Motorguide W55 Wireless
Underskinning
28 GPS

User avatar
steve1313
Posts: 679
Joined: Tue Aug 22, 2017 6:33 am

Re: Assuming I had a magical boat.....

#4 Post by steve1313 » Sun Jan 13, 2019 5:12 am

It looks like the Seven Marine 627 uses a 36 pitch prop. If my math is correct, that translates to about 190 mph at 100% efficiency. Obviously 100% efficiency isn't possible. If your magical boat hull was somehow as high as 50% efficient, you could be around 95 MPH.

That sort of makes sense considiering the 114 mph record referenced in the link above.
Steve
"Serendipity" - 2017 Sweetwater 2286 WB Tritoon w/ 150HP Yamaha
Slipped at Lake Anna, Virginia
Primary Residence: Richmond, Virgina
Lake House: Lake Anna, Virginia

User avatar
Liquid Asset
Posts: 486
Joined: Tue Jan 03, 2012 12:21 pm
Location: ortonville,mi

Re: Assuming I had a magical boat.....

#5 Post by Liquid Asset » Sun Jan 13, 2019 11:43 am

Good question but I think just floating the 627 h.p. would max out the old girl lol. I got to drive a Bennington with twin 300's last fall. Obviously it's a big boat but I was disappointed with the speed I saw. It was just a test drive so couldn't get carried away but I expect more than 50 mph with that kind of h.p. That said being 10' wide it catches a lot of wind!!!
2018 Tahoe ltz elite windshield powered by a 175 Mercury verado with sea legs
Rebuilt custom 20' 1983 riviera cruiser tritoon SOLD

2017 crew cab F-350 gets me to the lake !

User avatar
Marc K
Posts: 742
Joined: Fri Jun 01, 2018 4:35 am
Location: Eustace, TX

Re: Assuming I had a magical boat.....

#6 Post by Marc K » Sun Jan 13, 2019 4:23 pm

I'm thinking that with enough horsepower, you approach single point contact: The boat is flying above the water with little more than the prop in the water. The problems become aerodynamic control. The "magic" is not horsepower - it's maintaining level flight control.

So....... 200 MPH to 300 MPH like a drag boat?
Big and ugly but we love our 1999/2000 Crest II DL with a Yamaha F115

Post Reply