Thread: Battle of hp & torque

VE would win hands down.

Why? Since VE has small lobes, it has more power and torque down low to start up quickly, and by the time it's moving, the higher cams will kick in.

Even though it has less torque, it has it where it needs it most, down low to start moving the car.

That doesn't jive with his stated HP/TQ numbers. Show me that dyno graph. =P

All right. Here are four hypothetical dyno graphs. They aren't perfect, but they will get my point across.

There are basically two peaky graphs and two broad graphs. There is a broad and peaky VE graph and a broad and peaky DE graph. The area under the curve determines how well it will perform in the 1/4 mile. The higher the number the better. You will see that the DE could easily beat the VE if the VE is a peaky engine with a high power peak but not much else. The DE with the broad power band would win in this situation even though it has less peak power.
You will also see that the VE could easily beat the DE if the DE is a peaky engine with a high power peak but not much else. The VE with the broad power band would win in this situation even though it has less peak torque.









Also, keep in mind while torque is required to make these graphs and the power output it does not determine acceleration and simply the area under the power curve is what we're after. Nothing else matters.

I could keep going and make a graph with the DE specifications that would have more area under the curve than the VE with the beefy power curve. But then again, I could always make a graph with the VE beating that one. The VE is allowed to have 175 HP so it will always win out with area under the curve even though the torque output is required to be 130 or below.

Uhh its really simple, torque means nothing compared to HP. HP is defined as the power required to move a mass over a certain distance over a period of time. Torque is a force, independent of movement.

In drag racing, you should never use the lower portion of the power band, most of the time is spent in high RPM. So a car with a stouter power band will win, regardless of torque.

Which DE came with a 165hp rating stock?

Well, to be technical, Torque is not a force, it's force x distance, or moment. Torque is what the engine puts out (an angular force), horsepower is is torque in relation to time (in this case, time/rotation), which is power. There are two reasons for this 1) angular velocity carries momentum 2) an engine running at high RPM produces more energy in a given time frame.

Torque is the raw output, horsepower is the usable energy. Since they're directly related to each other, more torque means more horsepower. To put it another way, Imagine an engine that produces a flat 200ft-lb torque curve from 2000RPM to 7000RPM. That means that at ANY RPM it takes the same amount of force to stop or slow the acceleration. However, it takes a lot more energy to stop movement from a higher RPM.

Ok you caught me.... maybe the de has cams

This is only true in a common internal combustion engine where it cannot produce any torque without moving. The practice of linking torque and power to each other is a common mistake from those who are used to internal combustion engines. You can have torque without producing any horsepower. Electric motors do this all the time.
And because of that...

This is only true for internal combustion engines because of their inability to continue running once stopped. Torque can be produced without producing any [horse]power. This is not some nit-picky thing. This concept is essential to understanding what roles each play.

Hey thanks Ben I always like reading your responses.