Author Topic: HP needed for speed for a lakester (will work for cars also)....  (Read 20046 times)

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Offline 38flattie

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Re: HP needed for speed for a lakester (will work for cars also)....
« Reply #15 on: November 03, 2013, 05:05:21 PM »
Sum, what CD would a car like mine typically have? Backing into it using your calculator, and my fastest run of 189 MPH, I would estimate between a .4 and .45. Does this seem correct?


So, my HP needs look something like this:

CD                            .4                .45                  .5

HP for 189 MPH         482             535                  587

HP for 201 MPH         571             635                  698



This, of course, assumes my CD estimates are close!

HP Needed for a Specific Speed:      
 = = = = = = = = = = = = = = = = = = = = =    = = = = = = = = = = = = = = = = = = = = =    = = = = = = = = = = = = = = = = = = = = =
      
Input Rolling Resistance ======>   .024   <== (Note:
Input Car Weight =============>   5000   
Input Frontal Area in Sq. Ft. ====>    24.00   
Input Cd For Car Body Only====>    0.45   
Input Velocity in MPH =========>    201   
      
Body Drag Force =    1064   
      
HP for Rolling Resistance =    37   HP
HP Needed for Car Body =    598   HP
HP For 4 Tires/wheels =       HP
      
For this Speed =    201   MPH
      
Total RWHP Needed is =    635   HP

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Offline Sumner

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Re: HP needed for speed for a lakester (will work for cars also)....
« Reply #16 on: November 07, 2013, 01:05:53 AM »
Sum, what CD would a car like mine typically have? Backing into it using your calculator, and my fastest run of 189 MPH, I would estimate between a .4 and .45. Does this seem correct?...

Sorry I didn't see this here...guess that is why you PM'ed me  :-).  I'm just guessing but would say you are probably in the right range,

Sum