Good article on torque, horsepower, and gearing

**scheides** · 03-10-2010

Basic and over-simplified, but gets the brain working pretty good

http://www.jacobmcdonald.com/weblinks/hptq2.html

That article is good, but it is *way* over-simplified. We all know that engines don't produce their peak horsepower through the entire powerband. His logic in the end really would only stand if the theoretical cars were equipped with CVT's and held at peak horsepower.

Still, the logic is fairly sound. More horsepower = more acceleration. But I can tell you, having tons of torque down low just means you have more horsepower through your powerband. My BBK makes over 300whp at 4000rpm, but a SC61-powered car making similar peak power won't make it until 5500. Which car is faster? In the correct situation, mine; I don't have to shift as much to keep on accelerating!

Torque wins races really means having a wide powerband wins races, right? As long as peak output is similar, the car with more torque down low is going to be faster.

**Shane@DBPerformance** · 03-10-2010

Horsepower band, gearing, weight, traction, suspension, and driving wins races.

Some high peak TQ is the least important thing, unless you are stuck in the 1960s.

**scheides** · 03-10-2010

what's the difference between a 400whp supra and a 800whp supra? :P

**LingLing** · 03-10-2010

Quote:

Originally Posted by scheides

what's the difference between a 400whp supra and a 800whp supra? :P

How big the kid's trust fund is?

**Shane@DBPerformance** · 03-10-2010

Quote:

Originally Posted by LingLing

How big the kid's trust fund is?

Good answer!

**goodhart** · 03-10-2010

Quote:

Originally Posted by scheides

what's the difference between a 400whp supra and a 800whp supra? :P

If the 800hp Supra has a crap driver then nothing. With good drivers, the difference probably would be about 4 seconds.

A//// Guy · 03-10-2010

So basically, swiftys car wont be fast?

**Tachyon** · 03-10-2010

The thing most people fail to realize is it's about average wheel thrust after factoring in TQ multipliers (such as gearing, or wheel size) , rather than average engine HP or TQ.

This is one of the better articles I've found over the years that explains the basic concepts:

http://craig.backfire.ca/pages/autos/horsepower

Dyno graphs can be very deceiving because they don't show you the actual wheel force curves for each gear.

s1ngletracker · 03-10-2010

I think you make a valid point, Tachyon, but I think scheides points were mainly along the lines of power and torque distribution. Like you said, scalers bring it down or up, but don't change the shape/distribution of the curves.

**Tachyon** · 03-10-2010

Quote:

Originally Posted by s1ngletracker

I think you make a valid point, Tachyon, but I think scheides points were mainly along the lines of power and torque distribution. Like you said, scalers bring it down or up, but don't change the shape/distribution of the curves.

I was more appending to his information, rather then suggesting contrary