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Lightning
02-12-2004, 01:39 PM
A Definition of Acceleration.
* One Top Fuel dragster 500 cubic inch Hemi engine
makes more horsepower than the first 4 rows of
NASCARS at the Daytona 500.
* Under full throttle, a dragster engine consumes
1-1/2 gallons of nitromethane 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 for nitromethane,
the flame front temperature measures 7,050 deg F.
* Nitromethane 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, the crew worked
for free, and for once NOTHING BLOWS UP, each run costs an
estimated $1,000.00 per second.
* The current Top Fuel dragster elapsed time record is 4.441 seconds for
the quarter mile (10/05/03, Tony Schumacher). The top speed record is
333.00 mph. (533 km/h) as measured over the last 66' of the run
(09/28/03 Doug Kalitta).
--------------------------------------
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 past 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!

GlastronGuy
02-12-2004, 01:43 PM
"* Top Fuel engines turn approximately 540 revolutions
from light to light!
* Including the burnout, the engine must only survive
900 revolutions under load."
That's it? Wow!

mud duck
02-12-2004, 01:51 PM
Wow!!! :eek:

HOSS
02-12-2004, 02:03 PM
This is old and has been posted in bench racers and gearheads. With more info.:p

Sleek-Jet
02-12-2004, 02:14 PM
Do the math also. A vette doing 200mph is traveling 293 fps, so it would take 4.5 seconds to travel the 1/4 mile. So most likely you won't get passed in 3 seconds by the dragster.

uvindex
02-12-2004, 02:34 PM
Do the math also. A vette doing 200mph is traveling 293 fps, so it would take 4.5 seconds to travel the 1/4 mile. So most likely you won't get passed in 3 seconds by the dragster.
You're right that at 293 fps it takes the Vette 4.5 seconds to cover the running quarter mile. However, the post also states that the standing 1/4 record is 4.41 seconds, which means it covers the standing quarter quicker than the Vette covers the 200mph running quarter, and the dragster would pass the Vette before the finish line. :)

bordsmnj
02-12-2004, 02:53 PM
i love this thread . always pops up about every other month. always blows my mind. hemi not enough to drive the blower-fooooooock:cool:

Sleek-Jet
02-12-2004, 02:53 PM
Barelly, but not by a full second and a half as stated. :D

CA Stu
02-12-2004, 03:36 PM
My office chair has 850 hp and runs in the mid 7's in the 1/4
Thanks
CA Stu

fourspeednup
02-12-2004, 04:39 PM
They run top fuelers with paddle tires at the sand drags out here in Phoenix out by Lake PLeasant. It's only a 300 ft track but JEEBUS!!!! I was standing 20 ft away from 2 fuelers at full throttle! They aren't quite up to todays standards of power but the technology is about where the top fuelers were in the late 80's:eek:
It's funny how they aren't THAT loud (I had my fingers in my ears of course) but you feel it in yer gut!:cool:

Roland the Fisherman
02-12-2004, 05:20 PM
I have read this before and have a question.
10 or so years ago I wrenched on a well known TFH and made the rounds both IHBA and SBDA.
Back then the buz from everyone and the promos for the NHRA boasted of 3000+hp. The motors both for cars and boats ran 500cu in KB's (mostly) Anderson, Dart ect. heads, 1471 blowers, dual mags, dual fuel pumps, 92+% in the tanks and burned roughly the same amount of fuel per pass and so on just like today.
Now the same promos are claiming 6000+hp.
Heres the question: Where the hell they getting the additional 3000+ hp?
A couple of years ago I was told by a feuler mech. the reason for quicker times and faster speeds was'nt due so much to more hp but to the advances in clutch technology. The problem is bitchen clutches don't sell seats.
5 years from they will be producing 10,000hp and with standing room only.;)
Rolland

HOSS
02-12-2004, 05:24 PM
Agreed! Clutch technology and tire capability is what has been at the forefront of techno blasts for years now.

HighRoller
02-12-2004, 05:54 PM
Well, actually you have to remember that a fuel car can take a lot more power than a boat because the boat can't handle all the power at the start. They have sensors on the fuel cars that combine the data and give an accurate torque number using vehicle weight matched against G force, MPH and driveshaft RPM. Austin Coil showed ESPN the computer screen on a 4.90 run and the peak torque was just over 6000ft/lbs. It also showed peak horsepower of 6800 or so. So for the announcers to say 7000hp is not that far off. Each cylinder in a fuel car makes about 750HP. Remember, once you get to 280MPH it's like hitting a brick wall. A top fuel car will run 260-280MPH by the 1/8th mile. It takes the rest of the run to get an additional 50MPH. Granted, clutch technology has taken them to new ET records, but a good clutch won't put 330 on the board. That takes brute HP. Once the forged engine block was developed these guys started going nuts with the tuneup. As far as the boats, one other thing is that the boat technology is always 2 or 3 years behind the cars because of smaller budgets.