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ATAG_Bliss
Aug-14-2012, 03:03
http://www.youtube.com/watch?v=lpE1eqONJ8E&feature=fvwrel

A few fun facts about NHRA top fuel dragsters

* One Top Fuel dragster makes more horsepower than the first 4 rows of the Daytona 500.

* At full throttle, a Top Fuel dragster consumes 11.5 gallons of Nitromethane per run; a fully loaded 747 consumes jet fuel at the same rate but produces 25% less energy.

* A stock 426 HEMI does not produce enough horsepower to drive a Top Fuel supercharger (Basically, just to rotate the supercharger on a top fuel dragster requires 600 horse power)

* At full throttle the supercharger is ramming 3000 CFM of air into the cylinders. The mixture is so compressed that the engine is on the verge of hydraulic lock.

* Nitromethane burns yellow. The white flames seen above the exhaust stacks is actually Hydrogen, which has been dissociated from water by the heat of combustion.

* At stoichiometric, the nitromethane air/fuel ratio is 1.7:1. Flame front temperature is 7050 degrees.

* The dual magnetos produce 44 amps to each plug. This is enough current to arc weld.

* Spark plugs are totally consumed during a run. In fact, after half way, the engine is dieseling from the compression and the glow of the exhaust valves. After this point, the engine can only be shut down by cutting the fuel flow.

* To accelerate to over 300 MPH in 4.5 seconds the dragster must average 4 Gs. For the dragster to reach 200 MPH by half-track required 8 Gs.

* A Top Fuel engine only turns approximately 540 revolutions from light to light. Including the burnout, the engine must survive only 900 revolutions!

* Redline is quite high at 9500 RPM.

* Assuming all the equipment is paid off, the crew is working for free, and nothing blows up, each run costs $1000 per second.

that an NHRA Top Fuel dragster accelerates from 0 to 100 mph in less than .8-second, almost 11 seconds quicker than it takes a production Porsche 911 Turbo to reach the same speed?
that an NHRA Top Fuel dragster leaves the starting line with a force nearly five times that of gravity, the same force of the space shuttle when it leaves the launching pad at Cape Canaveral?
that an NHRA Funny Car is slowed by a reverse force more than seven times that of gravity when both parachutes deploy simultaneously?
that NHRA Top Fuel dragsters and Funny Cars consume between four and five gallons of fuel during a quarter-mile run, which is equivalent to between 16 and 20 gallons per mile?
that NHRA Top Fuel dragsters and Funny Cars use between 10 and 12 gallons of fuel for a complete pass, including the burnout, backup to the starting line, and quarter-mile run?
that NHRA Top Fuel dragsters and Funny Cars travel the length of more than four football fields in less than five seconds?
that NHRA Top Fuel dragsters can exceed 280 mph in just 660 feet?
that from a standing start, NHRA Top Fuel dragsters accelerate faster than a jumbo jet, a fighter jet, and a Formula One race car?
that a fuel pump for an NHRA Top Fuel dragster and Funny Car delivers 65 gallons of fuel per minute, equivalent to eight bathroom showers running at the same time?
that the fuel-line pressure for NHRA Top Fuel dragsters and Funny Cars is between 400 and 500 pounds, about 20 times greater than the pressure on passenger-car fuel pumps?
that depending on size and angle, the large rear wing on an NHRA Top Fuel dragster develops between 4,000 and 8,000 pounds of downforce?
that the 17-inch rear tires used on NHRA Top Fuel dragsters and Funny Cars wear out after four to six runs, or about two miles? Some brands of passenger-car tires are guaranteed for 80,000 miles.
that it takes just 15/100ths of a second for all 7,000 horsepower of an NHRA Top Fuel dragster engine to reach the rear wheels?
that it's desirable for an NHRA Top Fuel dragster to race with its front wheels inches off the ground for about the first 200 feet of the run? This ensures proper weight transfer to the rear wheels, a crucial part of a good launch and quick run.
that the nitromethane used to power the engines of NHRA Top Fuel dragsters and Funny Cars costs about $16 per gallon?



Perspective:

So you take your specially tuned $140,000 Lingerfelter Twin Turbo Corvette, and start back about a mile or so, accelerating as fast as you can, reaching your top speed of 200 MPH. This is really moving and would be something anyone would be proud of. Youre approaching the starting line where the Top Fuel dragster is sitting stopped waiting for you. As you cross the starting line, the light turns green.

Within 3 seconds you are deafened by the incredible whine of the dragster, which has caught up to you. He passes and beats you to the end of the 1320-foot quarter mile.
THAT is acceleration


Don't say you're ever too old:

Here's an 83 year old man going 220mph :)


http://www.youtube.com/watch?v=mIQXYVagmio&feature=related

Doc
Aug-14-2012, 08:15
Cool article Bliss! Wish I was able to do all that. :)

Dutch
Aug-14-2012, 10:39
:D

My MX-5 is green. :(

ATAG_Snapper
Aug-14-2012, 10:52
That was a good read and a fun watch. Any red-blooded man who feels the Eco-friendly urge to buy a Prius (or some such) should be forcibly sat down and obliged to watch this shit first! If he still buys in an ecologically responsible manner he should be declared Officially Cajone-Free! :D

(Apologies if I offended anyone Officially Cajone-Free).

335th_GRAthos
Aug-14-2012, 15:40
A Top Fuel engine only turns approximately 540 revolutions from light to light. Including the burnout, the engine must survive only 900 revolutions!


What are "revolutions"?

~S~

ATAG_Bliss
Aug-14-2012, 18:58
Revolutions refer to the complete turns the crankshaft makes. Basically RPMs are "revolutions per minute". So every time the crankshaft makes a complete circle you have a revolution.

335th_GRAthos
Aug-15-2012, 05:27
Ah, OK.

I take it for granted that the rear axle is direct (without differential) which would minimize any spin of one wheel only.

What makes it sure that it will go on a straight line though? Even a minor slip would cause problems at this acceleration I would imagine.

~S~

Doc
Aug-15-2012, 09:19
For those that are interested here's how they do it.


http://www.youtube.com/watch?v=-VF0JwxQqcA

ATAG_Snapper
Aug-15-2012, 09:24
Ah, OK.

I take it for granted that the rear axle is direct (without differential) which would minimize any spin of one wheel only.

What makes it sure that it will go on a straight line though? Even a minor slip would cause problems at this acceleration I would imagine.

~S~

They'd be a bugger to go through the drive-through at McDonald's!

roflmao (I'm such a funny guy, yes?)

ATAG_Bliss
Aug-15-2012, 10:17
Ah, OK.

I take it for granted that the rear axle is direct (without differential) which would minimize any spin of one wheel only.

What makes it sure that it will go on a straight line though? Even a minor slip would cause problems at this acceleration I would imagine.

~S~

Well sorta. In a top fuel dragster or funny car there is no transmission. It is direct drive as in the input shaft is splined to the clutch making a 1:1 ratio, but there is a rear differential. That is the only gear ratio these dragsters have - the ring and pinion gear in the rear end / differential. The reason both wheels will always spin at the same speed is they use a spool instead of your standard limited slip differential. A spool doesn't have side gears or spider gears to allow the axles to turn separately. They will always spin the same speed as each other.

As far as how to drive them straight :) - that's the driver. In a top fueler, you generally want the front wheels off the ground the 1st 200ft to maximize the amount of weight transfer to the rear wheels to get traction. The hope is that once the front wheels come down to steer it you are still going straight. What also helps is the rear wing. In a top fueler, that wing provides over 5 tons of down force to the rear tires. There's a few videos on youtube where the rear wing has broken. When that happens these cars immediately lose control.

Old_Canuck
Aug-23-2012, 12:26
:D Like a bullet in that first video. Yay Kinser. We're not getting older we're getting faster :)