Ski Boat Forum

General Category => General American Skier Discussions => Topic started by: Midskier on June 29, 2011, 01:29:30 PM

Title: Who has an Acme 541 prop?
Post by: Midskier on June 29, 2011, 01:29:30 PM

I know @ least one of you do , sorry I can't remember who, I know I shipped @ least one out to one of you guys
I'd like to get some good detailed info if possible

thanks

Dan T

Title: Re: Who has an Acme 541 prop?
Post by: Midskier on June 29, 2011, 01:56:21 PM

here is some info from my nephew Ben G

interesting results, the decision to go with the 543 over the 541
was made due to the fact that he is a slalom skier and wakeboarder
typically with 3 fat sacs and couple of 200+ lb buddies


(it looks much better in excel)

Boat Prop Test Sheet                              
                              
Boat Tuning                              
                              
Idle RPM      700                        
Base Timing      11.0                        
                              
Boat Performance                              
                              
Start Air Temp      57 F / Cloudy                        
End Air Temp      59 F / Cloudy                        
Start Water       Flat with a slight ripple from light wind             Pics below            
End Water       Flat with a slight ripple from light wind            Pics below            
Start Fuel Level      Just over 1/4 tank                        
End Fuel Level      1/8 tank                        
Weight in Boat      460 lbs (Drew , Ben, Tools)                        
                              
      13x13 Sandcast Prop         13x11.5 Acme Prop 543         Difference between 2 props      
       Run 1,Run 2,Average,Run 1,Run 2,Average,#1 vs #1,   #2 vs #2,Ave Vs Ave
RPM at this speed   
        15mph   1720   1710   1715   1910   1920   1915   190   210   200
   20mph   1960   1960   1960   2130   2150   2140   170   190   180
   25mph   2260   2220   2240   2540   2540   2540   280   320   300
   30mph   2640   2640   2640   2990   2970   2980   350   330   340
   35mph   3150   3140   3145   3500   3510   3505   350   370   360
   40mph   3800   3820   3810   4020   4070   4045   220   250   235
   WOT rpm   4370   4380   4375   4530   4530   4530   160   150   155
WOT mph      44.1   43.62   43.86   43.62   43.62   43.62   -0.48   0   -0.24
In-gear > 35mph time      
                        8.1   8.2   8.15   7.41   7.48   7.445   -0.69   -0.72   -0.705
35mph > 15mph time      
                       6.67   6.54   6.605   6.16   6.17   6.165   -0.51   -0.37   -0.44
                              
                              
   Test Specs                           
      For all RPM measurements a digital Tach was used                        
      For all static MPH measurements a GPS was used                        
      For dynamic measurements (accleration / deceleration) analog speedometer was used.  Hence the exact number is not accurate do to lag in the speedometer, but the change from prop to prop is accurate                        
      Boat has a slight hesitation when going from idle to WOT, when the boat did not hesitate off the line with a new prop the time was 7.12 seconds                        
      Boat was power tuned before start of test.