Proper formula to calculate flywheel hp?
Proper formula to calculate flywheel hp? Lets assume 15% driveline loss....actually, I have heard 18% driveline loss for M6 cars....but lets go with 15, what's the proper formula to calculate drive line loss?
We'll use my rwhp
You can go: 370 * 1.15 = 425.5
OR. : 370 / 0.85 = 435.29
Doing it the long way suggests the first method to be right:
370 * 15% = 55.5
370 + 55.5 = 425.5
So what's the deal, why do some people suggest dividing by .85??
Is there any formula that would compensate for 4.10 gears?
Manny
We'll use my rwhp
You can go: 370 * 1.15 = 425.5
OR. : 370 / 0.85 = 435.29
Doing it the long way suggests the first method to be right:
370 * 15% = 55.5
370 + 55.5 = 425.5
So what's the deal, why do some people suggest dividing by .85??
Is there any formula that would compensate for 4.10 gears?
Manny
there really is no formula for it. because your motor doesnt become less effecient as it makes more power which if you base your calc off a percentage then it would. as the more rwhp you make it will show a greater loss. an m6 10 bolt car is going to be as efficient as it gets so you prob wont be loosing much through the drivetrain of your car. id say your prob right aroun 410 hp-415 hp. the only way to know for sure is an engine dyno. but even then you cant account for drivetrain, accessory loss and the effeicency of your exhaust system.
There is no formula.
This topic has been beat to death lately. Who the hell cares what the car makes at the motor. All that matters is what goes to the ground (unless you advertise big numbers like half the damn import drivers I have spoke with).
Although people try to argue there is a % across the board, several members have run engine to chassis dyno testing to prove this is not the case.
This topic has been beat to death lately. Who the hell cares what the car makes at the motor. All that matters is what goes to the ground (unless you advertise big numbers like half the damn import drivers I have spoke with).
Although people try to argue there is a % across the board, several members have run engine to chassis dyno testing to prove this is not the case.
Let's take a look at the math:
Let X = Flywheel horsepower
So flywheel horsepower - 15% of flywheel power = rear wheel horsepower (RWHP)
X - 0.15 * X = RWHP
subtract on the left:
0.85 * X = RWHP
divide both sides by 0.85:
X = RWHP/0.85
-Geoff
Let X = Flywheel horsepower
So flywheel horsepower - 15% of flywheel power = rear wheel horsepower (RWHP)
X - 0.15 * X = RWHP
subtract on the left:
0.85 * X = RWHP
divide both sides by 0.85:
X = RWHP/0.85
-Geoff
I am not really concerend what my flywheel hp is, I couldn't care less, I just saw a few threads where people do it different ways, and since the results aren't the same, I wondered which way is the "right" way.
Nice algebraic breakdown of the .85 method!
Nice algebraic breakdown of the .85 method!
