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How Many Horsepower In A Twinkie?

April 25, 2008 – 1:05 am

Hostess Twinkies In my previous post, I discussed the British Thermal Unit (BTU) and how it converted into horsepower. The thing I didn't mention is that a BTU is very similar to a food calorie. A BTU is the energy needed to raise one pound of water by one degree fahrenheit. A food calorie is the energy needed to raise one kilogram of water by one degree celsius.

So, while it takes approximately 2544 BTUs to equal one hour of one horsepower, it only takes 640.8 food calories to deliver one hour of one horsepower. Essentially, when we convert food calories to mechanical horsepower, the conversion rate is roughly 10.68 food calories per minute at one horsepower.

Now, when we talk about the horsepower in cars, it gets complicated, because there are a gazillion ways to measure the horsepower of an engine. It doesn't actually change the value of a horsepower itself but there is energy lost between where the piston fires (where they're usually measuring the horsepower they state) and where the rubber meets the road. So when we calculate the number of twinkies needed to do that 0-60 run, we're going to be relying on the manufacturers' stated horsepower. That's going to make these equivalents really rough.

One thing I remember from The Fast and the Furious was the concept of a "10-second car." This was a car that could do a quarter mile (starting from a dead stop) in 10 seconds. We're going to introduce the concept of an X-twinkie car. That will be based on the Rough Equivalent of Hostess Twinkies it would take to do 0-60 in that car. Our formula is...

T = M / 13.39 * (1 / (60 / S))

Basically, a car's Twinkies is the manufacturer's stated horsepower (M) divided by the number of horsepower in a Twinkie (13.39) and then multiplied by the fraction of a minute that the 0-60 speed (S) represents.

Now, let's get down to business with a BMW M6. According to Wikipedia's M6 page, the early release models put out 507 horsepower and delivered a 0-60 time of 4.1 seconds. Rounding to the nearest tenth of a Twinkie, that's a 2.6-Twinkie car.

We'll compare that to a Hyundai Tiburon with the 2.7 liter V6 and the standard 5 speed manual transmission, putting out 172 horsepower and a 7.7 second time. Rounding to the nearest tenth of a Twinkie, it's a 1.6-Twinkie car.

Last, we'll bring back our friend the Smart ForTwo. According to dragtimes.com, this 70 horsepower inline 3 did 0-60 in 13.31 seconds. And that makes this little putt-putt a 1.2-Twinkie car.

What Rough Equivalents can you come up with for a Twinkie?



  1. 5 Responses to “How Many Horsepower In A Twinkie?”

  2. Dude. While I love this and hate yo burst your bouble a calorie is the amount of heat required to raise the temperature of one gram of water by 1 °C. Not a kilogram. So there is really only 0.01339 hp in a twinkie :(

    By Dave on May 1, 2008

  3. @Dave,

    That's why I made sure to specify these as food calories, not simply "calories." The calorie count for an item of food is actually in kilocalories. If a food item has "100 calories," that's 100,000 of the calories you're thinking of.

    Probably should have made that clearer.

    By Greg Bulmash on May 1, 2008

  4. http://en.wikipedia.org/wiki/Calorie

    Or just capitalize the C in Calorie! Keep up the good work! Don't mind me!

    By Dave on May 1, 2008

  5. http://en.wikipedia.org/wiki/Food_energy

    Good call! I'm just a dumb engineer :)

    By Dave on May 1, 2008

  6. First off, certain definitions need to be established in accuracy before this question can be answered correctly:

    1 Horsepower = 550 foot-lbs. of work per 1 second.

    1 Calorie = The amount of heat required to raise one gram of water 1 degree Celcius or
    1.8 degrees Fahrenheit.

    1 Calorie = 4.184 Joules.

    1 Joule = 1 newton times 1 meter, expressed in
    newton-meters.

    1 Newton = kilograms x 9.8 meters/sec squared.

    Newton-Meters = Metric measurement for Work.

    Foot-Lbs. = Standard measurement for Work.

    Power = Force x Distance/Time; measured in Watts or Joules, depending on either Standard
    or Metric applications.

    BTU (British Thermal Unit) - The amount of
    heat required to raise 1 lbs. of water by 1 degree Fahrenheit based on water's maximum density limit reached at 39.1 degrees F; Also a BTU can be used to define the difference in
    temperature in water between 59 degree F and
    60 degrees F; For approximation sakes, BTU is
    defined as the amount of heat required to raise
    one lbs. water 1 degree F.

    1 BTU = 251.90 calories.

    1 BTU = 1055 joules.

    1 BTU = 778.26 foot-lbs.

    Knowing this, in order to take the caloric potential energy found in a Twinkie at a stamped calorie count of let's say "300 calories", this means we have the following:

    300 calories x 4.184 Joules = 1255.20 Joules.

    1255.20 Joules / 1055 Joules = 1.19 BTU

    1.19 BTU x 778.26 foot-lbs = 926.13 foot-lbs.

    926.13 foot-lbs / 550 foot-lbs = 1.68

    No units yet, because it is a coefficient
    without any theoretical time limits presented.

    However if placed over the span of one second
    the theoretical HP would be 1.68 HP. This is
    not practical, since the total energy release
    of the twinky is unknown, and is specific to
    each person's metabolic rate.

    What is known, is that if in a controlled
    environment and only that twinkie is being
    assessed, and all energy is expended from that
    twinkie of "300 calories", there would be an
    approximate mechanical horsepower rating in
    work performed per second of 1.68 HP, for that
    given Twinkie.

    The human body as you know is an internal
    combustion heat engine as well. But based off
    exothermic heat energy release through
    chemical reactions.

    But if you get into four and two stroke gasoline-powered piston engines, the formula
    PLANK/33,000 foot-lbs per second can be used
    to calculate the theoretical Horsepower Rating
    of that given engine, based on specifications.
    Indicated Horsepower (IHP) is all theoretical and does not factor in the Friction Horsepower
    losses of the moving parts of the engine,
    the load on the flywheel and the loads of the
    application being driven by the engine. To
    calculate the true Horsepower, IHP later has to
    be derived to come up with Brake Horsepower
    leading also to torque rating at a given RPM.

    But for reference sakes, PLANK/33,000 foot-lbs./minute will allow you to calculate the Indicated Horsepower on a piston engine, which is defined as:

    P = Mean Effective Internal Cylinder Pressure

    L = Piston Stroke Length in feet.

    A = Piston Surface Area (kept in square inches)

    N = Number of Powerstrokes per minute; (on
    four-stroke piston engine this would be
    1/2 the RPM)

    K = Number of cylinders.

    33,000 foot-lbs/minute = 550 foot-lbs/sec times
    60 seconds = Horsepower constant over 1 minute
    since RPM is being used.

    For calculating Theoretical Horsepower of a
    given piston engine, also known as Indicated
    Horsepower (IHP), an example will be given
    below:

    If you have a four-cycle, gasoline-driven,
    eight cylinder, V8 automotive piston engine
    with a Mean Effective Internal Cylinder Pressure of 195 PSI, bore/stroke of 3.25"/3.00" running at 2500 RPM, calculate the
    IHP.

    P = 195 PSI

    L = 3/12 foot = 1/4 foot = 0.25 feet

    A = Pi x (r)squared = 3.14159 x (1.625 x 1.625) = 8.30 sqaure inches

    N = 2500 RPM/2 = 1250 powerstrokes/minute

    K = 8 cylinders

    (195 x 0.25 x 8.30 x 1250 x 8)/33,000 =
    122.61 IHP

    122.61 INDICATED HORSEPOWER

    Now if you wanted to get the Brake Horsepower
    out of this application, first you would either
    have to find out the work (rotational distance time force applied) per 1 revolution of the flywheel divided into (2 x 3.14159) this would get your the torque. Then from there multiply it back to (2 x 3.14159) times the RPM. Whatever that differs from the Indicated Horsepower Calculation, is the Friction Horsepower losses. IHP - Friction HP = BHP.

    This also points to the fact that you need motion or speed involved when figuring out Horsepower. This relates to the Twinkie "Horsepower" question. It would have to be applied to whatever application of 1.68 HP would be. Or 550 foot-lbs/second x 1.68 in terms of time, distance and force exerted within the person who ate that Twinky. So at best the 1.68 HP is just a rough base power rating for the Twinky. How it is expended over time, distance and force exerted is completely abstract.

    One last fact regarding Horsepower, is the fact that NO HORSEPOWER exists without a speed or motion of the application being factored into the equation.

    A good example of this aside from the previous ones, is turbine jet engines. It is simple to calculate the theoretical Horsepower rating of given Jet Propulsion Engines. But NO HORSEPOWER exists in any Jet Engine, even at peak thrust output UNLESS the aircraft is in MOTION!! So a Static Thrust rating (thrust while aircraft is held at rest) regardless to the amount of thrust is ALWAYS ZERO HORSEPOWER.
    Only when the aircraft rolls into motion, does the Static Thrust now change into Net Thrust.
    Net Thrust is when the given thrust rating is applied AND the aircraft IS in MOTION! Then Horsepower output is developing.

    An example of this, is with the following question:

    The Boeing 747-200 airliner has a max net thrust rating of 230,000 lbs. Calculate the mechanical horsepower equivalent of the thrust rating output of the four engines on the B747-200, when it is traveling at 500 MHP.

    1 Horsepower = 1 lbs. of thrust AT 375 MHP.

    375 MHP = 550 feet per second.

    This means that 230,000 lbs. of thrust will have a mechanical horsepower equivalent when traveling at 500 MHP of:

    500/375 = 1.33

    1.33 x 230,000 = 306,666.67

    306,666.67 HP IS THE MECHANICAL EQUIVALENT HORSEPOWER RATING OF THE B747-200 WITH 230,000 LBS. OF THRUST MOVING AT 500 MHP.

    THERE NEEDS TO BE SPEED OR MOTION INVOLVED IN ANYTHING FOR WHICH A HORSEPOWER RATING IS TO BE CALCULATED. IN PISTON ENGINES IT INVOLVES RPM. IN JET ENGINES IT INVOLVES FORWARD SPEED. WITH THE TWINKY IT MAY APPLIED TO THE AMOUNT OF FORCE THE PERSON EXERTS A CERTAIN DISTANCE. THE CALORIC HEAT RELEASE OF A 300 CALORIE TWINKY WILL ALLOW THE PERSON TO ACCOMPLISH AN "X" AMOUNT OF FORCE APPLIED TO A "X" AMOUNT OF DISTANCE OVER AN "X" AMOUNT OF TIME.

    IN ALL TECHNICAL CHEMISTRY AND PHYSICS TRAINING FOR ANY OF THESE TECHNOLOGY FIELDS, THERE'S ALWAYS A QUESTION WHERE A RUNNER EATS A HAMBURGER WITH A CERTAIN CALORIE COUNT, AND THE STUDENT IS TOLD TO CALCULATE THE THEORETICAL DISTANCE THIS RUNNER COULD ATTAIN, BASED ON HIS/HER WEIGHT (FORCE) AND THE DISTANCE HE/SHE ACCOMPLISHES OVER TIME, TO THAT CONSUMED HAMBURGER. THAT IS THE SAME THING WITH THIS TWINKY.

    By FAA Licensed Aircraft Technician on Aug 29, 2008

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