[Dbodily]

This probably does not belong here but... I got this via e-mail awhile back. I don't know if any one of you have seen it but for those of you who have not here it is.

ACCELERATION

TOP FUEL FACTS:

One Top Fuel Dragster 500 cubic inch Hemi engine makes more horsepower than the first four rows at the Daytona 500

Under full throttle, a dragster engine consumes one-and-a-half 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 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.

Full text: http://www.corvetteclubri.com/Acceleration.htm

[Arcuden]

A couple things to add that I've heard, but have not confirmed:

The driver in a top fuel dragster experiences more G's on launch than an astronaut blasting off into orbit.

Top fuel dragsters produce so much horsepower, nobody really knows for sure how much they produce. Conventional dynos are out of the question, so to gain an "estimate" on horsepower, the torsion (how much twist) experienced by the drive shaft is measured.

Again these are probably myths, but I've heard them several times.

And yes, this thread probably belongs in the lounge.

[Henry Highrise]

Very interesting...but it looks like a Lounge thread to me.

[malc]

Nasty G forces.............

[steve t]

yea, and they are loud too, i think that is what is wrong with my hearing, been to many races

[67 Deuce 4 Me]

Wow that is incredible No words can really describe that kind of acceleration. WOW!

[Rob Keller]

One pistons worth of power on a top fueler has way more power than a whole NASCAR engine

I was under the impression that a dragster uses about 200 gallons of fuel each pass

and its so unfreaking belivable how it feels like some one is passing by you lighting of sticks of dynamite one after anouther (the doppler effect) makes you T shirt dance with delight whooooooo hoooooooo

Gatornationals is right around the corner

if Wilma dont come and clobber us


Go FAST ...FAST

SR66

[Blazin72]

Yes, words cant begin to describe what it's like to watch two top fuelers roaring by at 300 mph. Once youve seen them in person, watching them on TV will never be the same.

[97Z28]

Originally Posted by Rob Keller

One pistons worth of power on a top fueler has way more power than a whole NASCAR engine

I was under the impression that a dragster uses about 200 gallons of fuel each pass

and its so unfreaking belivable how it feels like some one is passing by you lighting of sticks of dynamite one after anouther (the doppler effect) makes you T shirt dance with delight whooooooo hoooooooo

Gatornationals is right around the corner

if Wilma dont come and clobber us


Go FAST ...FAST

SR66

200 gallons a pass???? not quite THAT much, their fuel cells are only lik5 or 10 gallons... thats why they dont start the cars till they're at the line

[Kevin45]

This is a small comparison from Extreme MotorSports

One dragster's 500-inch Hemi makes more horsepower then the first 8 rows at Daytona. Under full throttle, a dragster engine consumes 1 1/2 gallons of nitro per second, the same rate of fuel consumption as a fully loaded 747, but with 4times the energy volume.

The supercharger takes more power to drive then a stock hemi makes.

Even with nearly 3000 CFM of air being rammed in by the supercharger on overdrive, the fuel mixture is compressed into nearly-solid form before ignition.

Cylinders run on the verge of hydraulic lock.

Dual magnetos apply 44 amps to each spark plug. This is the output of an arc welder in each cylinder.

At stoichiometric (exact) 1.7:1 air/fuel mixture (for nitro), the flame front of nitro methane measures 7050 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.

Spark plug electrodes are totally consumed during a pass. After 1/2 way, the engine is dieseling from compression plus the glow of exhaust valves at1400 degrees F. The engine can only be shut down by cutting off it's fuel flow.

If spark momentarily fails early in the run, unburned nitro builds up in those cylinders and then explodes with a force that can blow cylinder heads off the block in pieces or blow the block in half.

Dragsters twist the crank (torsionally) so far (20 degrees in the big end of the track) that sometimes cam lobes are ground offset from front to rear to re-phase the valve timing somewhere closer to synchronization with the pistons.

To exceed 300mph in 4.5 seconds dragsters must accelerate at an average of over 4G's. But in reaching 200 mph well before 1/2 track, launch acceleration is closer to 8G's.

If all the equipment is paid off, the crew worked for free, and for once NOTHING BLOWS UP, each run costs $1000.00 per second.

Dragsters reach over 300 miles per hour before you have read this sentence. * Top Fuel Engines ONLY turn 540 revolutions from light to light!

The redline is actually quite high at 9500rpm.

To give you an idea of this acceleration, the current TF dragster elapsed time record is 4.477 seconds for the quarter mile. This means that you could be coming across the starting line in your average Lingenfelter powered "twin-turbo" Corvette at 200 mph (on a FLYING START) and the dragster would BEAT you to the finish line FROM A DEAD STOP in a quarter mile distance!

[Rob Keller]

I dont get this part

Top Fuel Engines ONLY turn 540 revolutions from light to light!

can you explain this please
thanks

SR66

[NXS]

I have seen where they use the tire diameter, gear ratio and distance. I know you can figure it like this too:

4.5 seconds
8000 rpm

8000rpm/60sec=
133.333333 revs per sec
133.333333 x 4.5=
600 revolutions

[Rob Keller]

can you dumb it down some more ??

it just seems to me that it would be alot more than just 600 total revolutions but i never really thought about it ......................

no transmission just one hydraulic pump right

what about the differential whats going on back there?? is there a ratio or just straight up gears??
i once read that if a typical car didn't have a differental that it wouldn't be able to go slower than 50 MPH and top speed would be 250 to 300 MPH and reality in this??

SR66

[NXS]

No, I don't think I can make it any simplier? But I do know that there was a rules change at some point that lead to a 3.20 gear being the highest allowed with a three speed clutch.
and yes, if the gear ratio in a street car was not set at 3.00 or so they would top end about 200-300 mph if jacked up in the air.

[Blazin72]

Originally Posted by Rob Keller

can you dumb it down some more ??

it just seems to me that it would be alot more than just 600 total revolutions but i never really thought about it ......................

no transmission just one hydraulic pump right


SR66

Basically from when the green light lights up the crankshaft rotates only about 600 times before it crosses through the traps. Which means each cylinder fires only 300 times. By comparison if your car averages 2000 rpm on a 20 minute trip the engine will have completed about 40,000 revolutions, with each cylinder firing about 20,000 times.


Top fuelers are limited to a 3.20 rear gear. They utilize a direct drive transmission, no hydraulic pump. They use a series of clutches that are pneumatically controlled and programmed before the run. If the clutches are programmed too aggressively then they will send too much power to the tires and they'll go up in smoke. I believe the clutches are junk after every run.