Torque vs. horsepower

[Kai Thomsen 17]

Can someone explain to me why Briggs & Stratton changed their labels on the newer lawnmover engines ?

In the "old" days it was easy to see how many HP the engine had, 3.5 or maybe 5.5HP..

now.. i don't understand the new "gross torque" rating

[mr.pipes 4]

Here is a link to an article explaining the change.

http://www.washingtonpost.com/wp-dyn/conte...8021501732.html

[VinsRJ 721]

Classic story, its the other persons fault. :hide:

[Kai Thomsen 17]

Here is a link to an article explaining the change.

http://www.washingtonpost.com/wp-dyn/conte...8021501732.html

Thank you :hide:

[dobeleo 7]

I worked for a pressure washer pump then a coupling company for a while and saw how misleading these ratings were.

Torque is what matters!

[mavfreak 11]

Remember hp is a byproduct of torque, without torque you don't have hp

[Guest]

Remember hp is a byproduct of torque, without torque you don't have hp

Right, hp is just the rate at which torque is applied (w/o regard to units it's just torque X rpm) neither rating is more useful than the other if they're just peak ratings posted at say 3600 rpm. Just another way of saying the same thing. It's the 'continuous' rating that counts and that's usually a bit lower than what's on the sticker. Whats even more useful is the continuous duty (not peak) torque/rpm curve. I would think the flatter the curve is in the range you want to apply a steady load the better your machine will respond to fluctuations in demand and the more effective the governor will be at maintaining the speed you set. The machine should 'feel' more powerful. Cool topic. Hope I didn't hijack it or tell too many lies. I like to learn about that stuff.

I think gross vs net ratings just refer to different SAE testing standards for automobile powerplants but I'm not sure how they apply to lawn and garden equipment.

[shorts 182]

the saying goes,"horsepower sells, torque dous the work"

horsepower is a mathmatical computation based on 2 measurable facts, RPM and torque the formula is torque X RPM/5252 = HP.

If you want to know the power rating of an engine you need to find the dyno sheet or power curve, it will show the torque curve at different rpm's and usually the hp curve computation, usually the torque peaks and flattens out or falls off before the hp peaks at a higher rpm and then falls off.

all measurements are supposed to be corrected to sea level, temperature and humidity and a "standard" fuel Octane and addative package.