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weeds
6th February 2012, 10:02 AM
Read this through slowly and try to comprehend the amount of force produced in just under 4 seconds!There are no rockets or aeroplanes built by any government in the world that can accelerate from a standing start as fast as a Top Fuel Dragster!




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 V8 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 deg F.

Nitro methane burns yellow... The spectacular white flame seen above the stacks at night is raw burning hydrogen, dissociated from atmospheric water vapour 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 deg 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, the crew worked for free, and for once NOTHING BLOWS UP, each run costs an estimate $1,00000 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 blast across the starting line and 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!

rainman
6th February 2012, 10:23 AM
I reckon once I get the VNT, uprated intercooler, and diesel gas onto my 300Tdi 130 I'll go close.........

:Rolling:

James.

rovercare
6th February 2012, 10:44 AM
, the engine must only survive 900 revolutions under load.

!



I reckon once I get the VNT, uprated intercooler, and diesel gas onto my 300Tdi 130 I'll go close.........

:Rolling:

James.

?..

weeds
6th February 2012, 10:48 AM
Originally Posted by weeds https://www.aulro.com/afvb/images/imported/2016/08/768.jpg (http://www.aulro.com/afvb/general-chat/143809-definition-acceleration.html#post1622619)
, the engine must only survive 900 revolutions under load.

!



?..

633 revolutions if my maths is right....maybe the extra 270 is for the burnout pre-stage

rainman
6th February 2012, 10:49 AM
Ha! Perhaps rovercare :). I'm resisting the urge to run 22 psi.

James.

p38arover
6th February 2012, 01:33 PM
The information is such that it's almost impossible to believe!

Pedro_The_Swift
6th February 2012, 02:03 PM
repost!:p

and while entertaining,, not quite true,,

excape rockets on the top of manned space flights exceed those figures easily:o:o:o

clubagreenie
6th February 2012, 02:13 PM
Just go stand behind one on the line at start up and see how you feel. Puts Gold Coast rides to shame, I feel more in my stomach after that than one of their "rides".

TerryO
6th February 2012, 02:39 PM
Several years ago one Saturday night as we were finishing off the days work at Eastern Creek Raceway at one of our race meetings I was sitting up in the top of the control tower when the windows and walls started rattling violently. ...:eek:

There was also this on then off just as fast glow from over the hill and then I remembered that the Drag strip next door (about 1.5 k's away as the crow flies up and over a hill) had rocket dragsters doing demo's and runs down the 1/4.

The first time they started up and blipped the throttles the whole control tower shook. Pretty impressive, but as I was the last person in the building at the time no one believed me when I said what happened.

I've been there several times when top fuelers are on next door and while they are really loud they don't shake the building like the rocket cars did.

Mind you there is nothing in this world I have ever experienced that makes the air in your lungs vibrate like sitting on the hill watching two top fuelers going head to head. Everyone should experience it at least once in their lives I reckon.

cheers,
Terry

JDNSW
6th February 2012, 02:57 PM
The definition of Acceleration:-

a=dv/dt

John

clubagreenie
6th February 2012, 04:37 PM
You can't really blip the throttles on a jet car as such. I live on the far side of Seven Hills from the creek and we can still hear the top fuellers when running. If the winds right we can hear them all.

TerryO
6th February 2012, 05:02 PM
Are you sure they can't blip throttles on a Jet car Clubgreenie? ...;)

Here is a clip I went and found from Western Sydney when the Jet cars were there.


JET CARS RUN 7 SEC PASSES AT JET CAR CHALLENGE - SYDNEY DRAGWAY - 27.12.2010 - YouTube


cheers,
Terry

stevo
6th February 2012, 06:56 PM
Afterburners

Homestar
6th February 2012, 08:21 PM
Mind you there is nothing in this world I have ever experienced that makes the air in your lungs vibrate like sitting on the hill watching two top fuelers going head to head. Everyone should experience it at least once in their lives I reckon.

cheers,
Terry

Amen to that! I used to go to Calder Park years ago to watch to top fuelers, it is something that cannot be explained unless you have been there and felt/heard them.:)

SuperMono
6th February 2012, 09:42 PM
The definition of Acceleration:-

a=dv/dt

John

Thank you, that sorts out the definition of 'average acceleration' anyway :)
Do you want to start adding vectors :wasntme:
I have seen this set of dragster trivea posted a number of times.
Top Fuel cars are impressive, but a lot of the stuff written is either misleading, myth or just wrong.

My favorite is this: "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."

Examined in a literal way there is so much wrong with that statement that it is worth a chuckle by itself.

But as I said, they are impressive, up close more than impressive, likely to leave you leaking, deaf of blind (at least temporarily).

I love top fuel rails and funny cars......
A complete day of racing done and dusted in less than 30 seconds!

Blknight.aus
6th February 2012, 09:53 PM
My favorite is this: "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."


I can buy into that.. providing they're talking about the nitro in its gaseous state and not liquid state