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Re: some calculations
I haven't try it yet ,because I don't know the frontal area of my
In the article ,they try to tell us how much more power we
need just to increase top speed a few mph.
their example is Porsche 944
frontal area of 20.45 sq ft.
assume the target speed is 200 mph
Power needed is 8.7E-06*0.33*20.45*200^ = 469.8 HP.
Oh,I just see the other one.
new power/old power = (new speed/old speed)^3
Their Porsche now has 331 rear wheel h.p. and does 175 mph . they
input these info. in the second formular and use 200 mph as new speed
,the new power is 493 which is very similar to 469.8 from the first
I don't think it is very accurate ,because many tuned German sedan
also does 175 mph with about 300 *flywheel h.p.* (all of their h.p. means
rear wheel h.p.,which is much lower than flywheel h.p.)
Now I'll try the second formular for my car,but I'll use flywheel
h.p. anyway. old speed=150 old power =230
new speed=? new power = 280
the answer is 160 mph..
they convert Porsche's331 pony in to
flywheel h.p. of 400.!) 469.8 h.p. they need is still a rear wheel h.p.
I hope this is detailed enough