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      06-09-2011, 01:29 PM   #67
e1000
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Just imagine you're on a pedal bike.

torque is how much force you can put down on that pedal

rpm is rpm


Now, let's compare two very different engines, just to piss everyone off, i choose the N54 and the S65.

The N54 is a big bodybuilder dude, lots of strength in his legs, but he can't pedal very fast.

The S65 is a skinnier guy, lets say Lance Armstrong, not as powerful, but he can pedal like there's no tomrorow.

We've all ridden pedal bikes before right.

So, N54 guy needs to upshift and pedal very hard to make speed. As gearing is taller, the rear wheel spins faster, but it's also much harder to pedal.

The S65 guy can stay in lower gears, which is easier to pedal, meaning greater acceleration, but in order to continue to accelerate, you need to pedal faster. Of course, the N54 guy just doesn't have that option. The S65 guy however, does, so he takes the mechanical advantage that the gears provide, and spins his feet faster to get the rear wheel moving faster.

HP is the description of how much resulting power each has. Assuming the torque curve is identical, a car making 300hp and 250ft-lbs of torque can be made to perform identically to a car making 300hp with 150ft-lbs of torque.
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      06-09-2011, 03:06 PM   #68
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Quote:
Originally Posted by e1000 View Post
Just imagine you're on a pedal bike.

torque is how much force you can put down on that pedal

rpm is rpm


Now, let's compare two very different engines, just to piss everyone off, i choose the N54 and the S65.

The N54 is a big bodybuilder dude, lots of strength in his legs, but he can't pedal very fast.

The S65 is a skinnier guy, lets say Lance Armstrong, not as powerful, but he can pedal like there's no tomrorow.

We've all ridden pedal bikes before right.

So, N54 guy needs to upshift and pedal very hard to make speed. As gearing is taller, the rear wheel spins faster, but it's also much harder to pedal.

The S65 guy can stay in lower gears, which is easier to pedal, meaning greater acceleration, but in order to continue to accelerate, you need to pedal faster. Of course, the N54 guy just doesn't have that option. The S65 guy however, does, so he takes the mechanical advantage that the gears provide, and spins his feet faster to get the rear wheel moving faster.

HP is the description of how much resulting power each has. Assuming the torque curve is identical, a car making 300hp and 250ft-lbs of torque can be made to perform identically to a car making 300hp with 150ft-lbs of torque.
nice job dumbing it down. I agree it's frustrating that so few people understand hp vs. tq.
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      06-09-2011, 03:17 PM   #69
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as a point of reference to you "torque" guys, a modern F1 engine produces +750 hp, spinnging at an artificially limited 19,000rpm. This means that the engine only produces a touch over 200 lb-ft of torque!
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      06-09-2011, 03:23 PM   #70
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Thanks a lot e 1000! That was definatley Breaking it down Barney style! LOL!
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      06-09-2011, 05:49 PM   #71
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beautiful!
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      06-09-2011, 05:52 PM   #72
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Quote:
Originally Posted by e1000 View Post
Just imagine you're on a pedal bike.

torque is how much force you can put down on that pedal

rpm is rpm


Now, let's compare two very different engines, just to piss everyone off, i choose the N54 and the S65.

The N54 is a big bodybuilder dude, lots of strength in his legs, but he can't pedal very fast.

The S65 is a skinnier guy, lets say Lance Armstrong, not as powerful, but he can pedal like there's no tomrorow.

We've all ridden pedal bikes before right.

So, N54 guy needs to upshift and pedal very hard to make speed. As gearing is taller, the rear wheel spins faster, but it's also much harder to pedal.

The S65 guy can stay in lower gears, which is easier to pedal, meaning greater acceleration, but in order to continue to accelerate, you need to pedal faster. Of course, the N54 guy just doesn't have that option. The S65 guy however, does, so he takes the mechanical advantage that the gears provide, and spins his feet faster to get the rear wheel moving faster.

HP is the description of how much resulting power each has. Assuming the torque curve is identical, a car making 300hp and 250ft-lbs of torque can be made to perform identically to a car making 300hp with 150ft-lbs of torque.
Very well put. But to add to it, on different vehicle applications, like a truck, you need torque. Like e1000 was stating, if you have the mechanical gearing, you can overcome the lack of torque. Just like the unimog, which basically runs a C230 mercedes motor, it uses gear ratios to get the car moving and over rocks with a relatively low hp/torque motor.
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      06-11-2011, 07:09 AM   #73
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Here is the dyno printout from that session, all numbers are at the wheels :
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      06-14-2011, 06:31 PM   #74
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great numbers!
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      06-25-2011, 03:41 PM   #75
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Quote:
Originally Posted by KTM505SX View Post
Bananas!
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      06-25-2011, 04:01 PM   #76
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Is that 604 at the wheels?
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      06-25-2011, 06:13 PM   #77
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Quote:
Originally Posted by chriszeh View Post
Is that 604 at the wheels?
yes whp wheel horse power
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      06-25-2011, 08:39 PM   #78
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Holy balls nice. Sorry didn't look far enough into the post. See the dyno graph now. That is sick. So 700 to 750 at the crank!
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