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if a engine has a 20bhp what is the hp of this motor????
johnp0154
Very little.
DodgeRida67
Go to the Gearhead Garage... That'll answer some questions.. :thumbs:
R34RB30DETTV
Actually johnp0154, it is "BRAKE Horsepower" and not "Break Horsepower" to
imply a load placed on something rather than to break something by damaging
it. BHP is the acronym and it means:
as per dictionary.com:
"The actual or useful horsepower of an engine, usually determined from the
force exerted on a friction brake or dynamometer connected to the drive
shaft."
This means that BHP is the actual USEFUL power rating that we care about.
If that motor you were talking about was 20BHP, that means that it is
capable of 20 useful horsepower to accomplish some level of work that it
was employed to do. It is basically FINAL power rating and therefore the
rating we care about.
This would be like rear wheel horsepower of a car's engine capability. If
you have a 1971 Chevelle SS 396 and the engine is putting out 400
horsepower from the crankshaft, we don't care about that because WE CARE
about the fact that once that power is transfered through the driveline
(transmission to the driveshaft and through the rear differential to the
rear tires) we now have 380BHP, say. The horsepower of that car is 380BHP
(useful horsepower). We've lost the other 20HP mainly to frictional losses
and heat/noise as well...so who cares about that 20HP. It is gone. Does
that answer your question? :smoke:
cmeseadoin
Again I get the chance to say, HUH? While you are correct about power loss
through the drivetrain, that has nothing to do with the term 'brake
horsepower'. You are guilty of "D". I know I've answered this previously
but here goes again.
SAE Gross Horsepower or Brake horsepower (bhp) was the standard horsepower
measurement by the automotive industry up until 1971. Brake Horsepower
Power is measured at the flywheel with no load from a chassis or any
accessories and with fuel and ignition operations under ideal conditions.
An accessory is anything attached to the engine, by any means, which is not
required for basic engine operation. By this definition, this would include
a power steering pump, smog pump, air conditioning compressor and an
alternator. Ideal conditions, often called laboratory conditions, are
standardized settings for use during horsepower measurement. During the
1960s they consisted of a barometric pressure of 29.92 Hg and a temperature
of 60 degrees F.
SAE Net Horsepower became the standard measurement in 1972, and is still
used today. SAE Net horsepower is the horsepower generated by the engine at
the flywheel with all accessories attached. This change was made to reflect
the numerous energy sapping accessories that cars began to have, such as an
A/C Compressor and alternator, and thus was a better representation of the
actual power generated by the engine. This number is always lower than the
SAE Gross horsepower. Therefore, the same engine could have been rated in
1971 as 360 SAE Gross Horsepower and in 1972 as 300 SAE Net horsepower
without any reduction in "power."
vwhobo
OHHHHHHHHHHHHHH LOOK, I am guilty! :hi: Logically though, if the
definition of BHP is the "useful" amount of power from an engine....that is
final drive power to me. I could not care less about what the engine has
at the crank, rather, I want to know what it has at the rear wheels via
driveline losses with an automobile.
I still read horsepower ratings in mags and such very often that speak in
terms of BHP. If SAE has a new standard, why is it still printed.
I guess I'm just GUILT as charged, spank me! :laughing: :orglaugh:
cmeseadoin
