Prop slip

Taz · 11-04-2005, 08:32 PM

What sort of slip was i running at? i was going along at 55mph at 5k and i was running a 25 pitch laser 2

Just wondered in theory what my top speed would be?

BluFin · 12-04-2005, 08:02 AM

Assuming g'box ratio of 1:87 slip was 13.12%

Edit: what is your max RPM for that prop?

Taz · 12-04-2005, 06:44 PM

I belive the engine will go to 9k so im told what speed in theory would that be?

Silversurfer · 12-04-2005, 10:00 PM

If I am doing it right 99mph! ! !http://www.rbbi.com/folders/prop/propcalc.htm

I reckon you would be lucky to achieve that though Taz!!!

Jon Fuller · 12-04-2005, 10:09 PM

I make it 114mph before slip...theoretically

BluFin · 13-04-2005, 08:27 AM

I have come up with 113 MPH rounded down to the nearest (Mph) with no slip.
What percentage of that you manage is down to set up & trimming of the boat there will be trade off's
in deteration of handling & useability.

Edit: There will always be slip it is just at what % it will be

Jon Fuller · 13-04-2005, 08:43 AM

but don't lose sight of the fact that your top speed is dependant on many things, gear ratio, prop, rpm, but most importantly, do you have adequate horse power to push the boat in question (with it's setup) to the speed your calculating? if you aint got that, then you goin a ton neever.

Matt · 13-04-2005, 09:23 AM

Lucky to survive that, more like.

Quote:

Originally posted by Silversurfer
I reckon you would be lucky to achieve that though Taz!!!

BluFin · 13-04-2005, 10:36 AM

It's all theory - but whats achiveable is another story.
I dont think you will see 9k ok a 25" if you did it would be jacked so high you would need remote pic ups + would handle like shite.

Heck thats why we love playing with boats wastes hours........................

Silversurfer · 13-04-2005, 11:40 AM

So basically it all a load of B*LL*CKS! Surely boat weight how much fuel etc come into the equation as well.

BluFin · 13-04-2005, 11:43 AM

exactly.............
it's only the Theoretical maximium that could be obtained

Taz · 13-04-2005, 07:48 PM

Yeah all i wanted was da in theory answer at 80mph the boat cavitates like poo keeps rocking side to side must be set up wrong or

What are phantoms speed rated to is there such a thing?

Silversurfer · 13-04-2005, 08:08 PM

I would change the prop first taz, whats Burty using he made 80 mph didnt he?

Taz · 13-04-2005, 08:31 PM

22.5 chopper i belive ive borrowed a 24 pitch chopper but hopefully have a 23 pitch chopper on da way

Burty · 13-04-2005, 10:42 PM

its a 22.5" ET lightening actually and recon i can do around 85mph
@7800RPM thats why i keep telling you Taz that you need around a 21" to enable to use the full potential of your mota

JamesM · 13-04-2005, 11:10 PM

its not motor its mota

Burty · 13-04-2005, 11:13 PM

Quote:

Originally posted by Johnny Boat Dude
its not motor its mota

Sorry dude and thanks for that. I changed it now