How is horse power rated?
How is horse power rated?
The electrical equivalent of one horsepower is 746 watts in the International System of Units (SI), and the heat equivalent is 2,545 BTU (British Thermal Units) per hour. Another unit of power is the metric horsepower, which equals 4,500 kilogram-metres per minute (32,549 foot-pounds per minute), or 0.9863 horsepower.
How many horsepower does a 1987 Mustang have?
The Fox Bodies are blessed with an easily-modifiable engine bay, and several components can be directly replaced with high-performance variants that can give up to a 35 horsepower combined performance boost.
When did they start using net horsepower ratings?
Net ratings have existed for many years, but before 1971, most U.S. automakers preferred to quote the more generous gross figures. Net figures might appear in shop manuals, technical papers, or other factory literature, but rarely showed up in advertising.
Are there any misunderstandings about vintage horsepower ratings?
There are a lot of misunderstandings among car enthusiasts and historians about vintage horsepower ratings.
What was the purpose of the gross horsepower rating?
The gross ratings served a variety of useful marketing and political purposes, but as a realistic measure of engine output, they left much to be desired.
Net ratings have existed for many years, but before 1971, most U.S. automakers preferred to quote the more generous gross figures. Net figures might appear in shop manuals, technical papers, or other factory literature, but rarely showed up in advertising.
There are a lot of misunderstandings among car enthusiasts and historians about vintage horsepower ratings.
When did SAE stop using gross horsepower ratings?
The final straw was the passage of a California law requiring that new cars sold in that state advertise only the more conservative SAE net figures beginning with the 1972 model year. Faced with that reality, manufacturers decided it was time to abandon the gross rating system entirely.
The gross ratings served a variety of useful marketing and political purposes, but as a realistic measure of engine output, they left much to be desired.
