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Anyone know how or where I can find a converter for whp to crank hp for awd cars? I just want to know how much 460whp translates into crank and how much 521whp translates into crank. Thanks!
 

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Meh, the dyno results alternate from one dyno to the other and from one car to the next depending on break in etc.etc, too many variables, the calculator is close enough
 

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Curious why crank is a useless number? I am using it myself to calculate what components I need for my future engine build.
 

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Mine was in the 30% range .... its useless because what does it prove?
its actually a good gauge if you want to see how you stack up against another car to figure out the lbs per horsepower. divide the the weight by crank hp and you will have a really close way to see who will win a race
 

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not really there are too many factors (actual weight actual power both of which are usually an estimate, gearing, suspension setup, etc, etc), too must estimation. Put them on a track that will tell you which is faster, its the one that wins. The rest is ricer math bullshit when your talking about modded cars.

I am in for the above mentioned calculations.
 

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not really there are too many factors (actual weight actual power both of which are usually an estimate, gearing, suspension setup, etc, etc), too must estimation. Put them on a track that will tell you which is faster, its the one that wins. The rest is ricer math bullshit when your talking about modded cars.

I am in for the above mentioned calculations.
is this why many magazines like motor trend, car and driver and others always mention pounds per hp as a great way??? How is actual weight and actual power an estimate? thats what a dyno and a scale is for....read a car mag and and you will see its a great way to measure how fast your car is and stacks up to others
 

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Just calculate with the butt dyno. If that's satisfied, life is good!
Except the butt-dyno is a huge liar. What 'feels' fast, may not be as fast/quick/powerfull as another car that doesn't.

Crank power is a meaningless number.
Except when you're building for power and need to size things like injectors/pump/MAF/etc.:D
 

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is this why many magazines like motor trend, car and driver and others always mention pounds per hp as a great way??? How is actual weight and actual power an estimate? thats what a dyno and a scale is for....read a car mag and and you will see its a great way to measure how fast your car is and stacks up to others
What is your weight and CHP? Do you know? Has your car been on a scale, has the other car been on the same scale or same brand scale? What was the correction on your Dyno. What number did you use to convert to CHP? Was the other car on the same dyno, same conditions. How does gearing come into play. Since I thing drag racing is worthless what is your suspension setup?

That's why, those are called estimates. Now if only Motor Trend were the end all be all of automotive expertise we would be all set, thank god for car mags and their wealth of information :rofl:
 

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not really there are too many factors (actual weight actual power both of which are usually an estimate, gearing, suspension setup, etc, etc), too must estimation. Put them on a track that will tell you which is faster, its the one that wins. The rest is ricer math bullshit when your talking about modded cars.

I am in for the above mentioned calculations.
He needs to know ridiculous things like resistance from transmission fluid at xxx temperature, tire rolling resistance, wheel weight distribution.... :p
 

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What is your weight and CHP? Do you know? Has your car been on a scale, has the other car been on the same scale or same brand scale? What was the correction on your Dyno. What number did you use to convert to CHP? Was the other car on the same dyno, same conditions. How does gearing come into play. Since I thing drag racing is worthless what is your suspension setup?

That's why, those are called estimates. Now if only Motor Trend were the end all be all of automotive expertise we would be all set, thank god for car mags and their wealth of information :rofl:
sounds like like someone is over analyzing......No offense but i trust car experts over you. lbs per hp is a great way to gauge your car against others. not exact but a good estimate....,regardless of what you or other "car experts" think
 

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Crank HP per pound is near useless. WHP per lb is much more useful since crank HP isn't the value that moves the weight... WHP does.

I can't wait for the day that manufacturers just give WHP numbers instead of a useless crank HP number that the English and tools in civics can sit around and argue. Since the HP you actually get out of the car at the wheels is what really does work, it shouldn't be allowed to advertise crank HP. If the car has 200 crank HP, but loses 100 HP in the drivetrain, they can still sell it as a 200HP car. :tdown:

Will the above mentione day ever come? Probably not, since electrical cars are just around the corner and have no "drivetrain" to speak of, just motors attached to wheels. :(
 
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