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General control line discussion => Open Forum => Topic started by: Mike Griffin on November 29, 2021, 12:14:40 PM
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I know this is not model planes but it is astounding.
THE DEFINITION OF ACCELERATION
One top fuel dragster
500 cubic inch Hemi engine
makes more horsepower
than the first 4 rows of stock cars
at the Daytona 500.
It takes just 15/100ths of a second
for all 6,000+ horsepower
of an NHRA Top Fuel dragster engine
to reach the rear wheels.
Under full throttle,
a dragster engine consumes 1-1/2 gallons of nitro methane per second;
a fully loaded 747 consumes jet fuel at the same rate,
with 25% less energy being produced.
A stock Dodge Hemi V-8 engine
cannot produce enough power
to drive the dragster's supercharger.
With 3,000 CFM of air
being rammed in by the supercharger on overdrive,
the fuel mixture is compressed
into a near-solid form before ignition.
Cylinders run on the verge of hydraulic lock at full throttle.
At the stoichiometric (stoichiometry: methodology and technology by which quantities of reactants
and products in chemical reactions are determined)
1.7:1 air/fuel mixture of nitro methane,
the flame front temperature measures 7,050 degrees F.
Nitro methane burns yellow.
The spectacular white flame seen above the stacks at night is raw burning hydrogen,
dissociated from atmospheric water vapor by the searing exhaust gases.
Dual magnetos supply 44 amps to each spark plug.
This is the output of an arc welder in each cylinder.
Spark plug electrodes are totally consumed during a pass.
After halfway, the engine is dieseling from compression,
plus the glow of exhaust valves at 1,400 degrees F.
The engine can only be shut down by cutting the fuel flow.
If spark momentarily fails early in the run,
unburned nitro builds up in the affected cylinders
and then explodes with sufficient force
to blow cylinder heads off the block in pieces
or split the block in half.
In order to exceed 300 mph in 4. 5 seconds,
dragsters must accelerate an average of over 4G's.
In order to reach 200 mph (well before half-track),
the launch acceleration approaches 8G's.
Dragsters reach over 300 miles per hour
before you have completed reading this sentence.
Top fuel engines turn approximately 540 revolutions
from light to light!
Including the burnout,
the engine must only survive 900 revolutions under load.
The redline is actually quite high at 9,500 rpm.
Assuming all the equipment is paid off,
that the crew worked for free,
and for once NOTHING BLOWS UP,
each run costs an estimate $1,000.00 per second.
The current top fuel dragster elapsed time record is 4.428 seconds for the quarter mile.
(11/12/06, Tony Schumacher, at Pomona , CA ).
The top speed record is 336.15 mph as measured over the last 66' of the run.
(05/25/05 Tony Schumacher, at Hebron , OH ).
Putting all of this into perspective:
You are driving the average $140,000 Lingenfelter 'twin-turbo' powered Corvette Z06.
Over a mile up the road,
a top fuel dragster is staged
and ready to launch down a quarter mile strip as you pass.
You have the advantage of a flying start.
You run the 'Vette hard up through the gears,
and you blast across the starting line
and you pass the dragster at an honest 200 mph.
The 'tree' goes green for both of you at that moment.
The dragster launches and starts after you.
You keep your foot down hard,
but you hear an incredibly brutal whine that sears your eardrums
and within 3 seconds,
the dragster catches and passes you.
He beats you to the finish line,
a quarter mile away from where you just passed him.
Think about it,
from a standing start,
the dragster had spotted you 200 mph
and not only caught,
but nearly blasted you off the road
when he passed you
within a mere 1,320 foot long race course.
....... and that my friend, is ACCELERATION
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Amen Brother....
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And here I thought it was going to something simple, like a change in speed or direction.
Sent from my SM-N986U using Tapatalk
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Hi Mike,
I've seen something like that before......only with a little lower numbers. Still VERY impressive!
I went to San Jose to see my friends friend (a few years ago) and he was/is a dragster builder. He showed us an aluminum con rod that had one run on it. The crank end had an egg shaped hole twice the size of the original! How it stayed together is beyond me!
Amazing stuff, Jerry
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....... and that my friend, is ACCELERATION
No, it is insanity! but cool.
Ken
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My speed and racing mentor when I was young was Norm Drazy inventor of the screw type blowers. Founder of PSI Supercharges. Some here might remember some of his models.
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I just have a hard time comprehending power and speed of that magnitude. I am with Ken, I do not think I would want to be strapped into one of those things.
Mike
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I just have a hard time comprehending power and speed of that magnitude. I am with Ken, I do not think I would want to be strapped into one of those things.
Mike
Oh, I would love the opportunity. I get giddy just thinking about it.
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Pulling more G's than an astronaut does at any point in the flight. Heck they don't even shove satellites that hard at any point.
Ken
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Pulling more G's than an astronaut does at any point in the flight. Heck they don't even shove satellites that hard at any point.
Ken
My Laser would pull 8.5 G's. That hurts.
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Impressive Mike, but those are old specs.
Off the top of my head and without going into great detail, the current NHRA Top Fuel and Funny Car engines are now over 10,000 hp while still running within the same 500 c.i. V-8 limit. It's gotten to the point that it's impossible to get truly accurate dyno figures on them because the the power comes on so violently and abruptly. Current HP estimates are actually 11,000 or more. One cylinder produces significantly more power than an entire NASCAR engine. Another way to think about that is it takes 13 or 14 NASCAR cars to equal one Top Fuel dragster in horsepower.
Fuel consumption? Last I knew is (and this from is at least 10 years ago) that from engine startup, performing the burnout then backing up and making a full pass burned 12 plus gallons of fuel.
Quite some time ago, when the two classes started running 300 mph in the 1/4 mile consistently, the time from 0 to 100 mph was 9/10ths of a second. Think about that next time you leave a stoplight. When they got to running 330 pretty consistently the NHRA shortened the race distance from 1/4 mile to 1000 feet for the nitro classes (Top Fuel and Funny Car). That change was intended as a safety measure. Nowadays they're back to running 330 mph plus in that 1000 feet while going from 0 to 100 mph in 8/10ths of a second or less. Today, on a typical 330 mph pass they're running 280-ish mph at the 1/8th mile mark. Keep in mind, that's 0 to 280 in an 1/8th mile.
I chased the NHRA trail for quite a few years with a lot of friends, this being top-level drivers, team owners and crew members (including Schumacher, Force, Prudhomme, etc.), that ran or still run in the two nitro categories. The nitro cars are something that simply have to be witnessed to comprehend, and even then it takes a while for it to to fully register. Until you see them run in person you simply cannot imagine how much sheer racket one 500 cubic inch V-8 can make, seriously. Standing at the starting line when a pair of them launch is utterly mind boggling until you get used to it. There is no TV loud enough, no video, or any description that even begins to come close. This is why it's the baddest ass motorsport there is, on the ground anyway. :)
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Pulling more G's than an astronaut does at any point in the flight. Heck they don't even shove satellites that hard at any point.
Ken
I got a ride in the back seat of an F-15 in 1974. There was a G meter on the panel that read 3G's in a turn. I was stiff and sore for several days after that experience.
(Yes, this is off topic but the F-15 was/is designed for 7G's, the F-16 was/is for 9G's with its semi-prone pilot)
Keith
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When things are perfect, today's typical performance results are as I described above. This is Brittany Force two years ago in Las Vegas...
https://www.youtube.com/watch?v=YuE-I9QB_fY
But, when they're not perfect...
https://www.youtube.com/watch?v=Xnd3DJBOpsQ