Acelleration

[Ibrox90]

I found this in my random internet ponderings:

"A lesson in acceleration but first some useful information:

One Top Fuel Dragster 500 cubic inch Hemi engine makes
more horsepower than the first 4 rows at the Daytona 500.

Under full throttle, a Top Fuel Dragster engine consumes
1.5 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 426 Hemi V8 engine cannot produce enough
power to drive the dragster’s supercharger.

With 3000 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 1.7:1 air/fuel mixture for nitro methane
the flame front temperature 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.

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 half way, the engine is dieseling from compression
plus the glow of exhaust valves at 1400 degrees F. The
engine can only be shut down after cutting the fuel flow.

If spark momentarily fails early in the run, unburned nitro
builds up in the affected cylinder 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 at 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 mph 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 red line is actually quite high at 9500 rpm.

The Bottom Line; 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. The top speed record is 333.00 mph as measured
over the last 66’ of the run.

Putting all of this into perspective:

You are driving the average $140,000 Lingenfelter twin-turbo
Corvette Z06. More than a mile up the road, a Top Fuel
dragster is staged and ready to launch down a measured
quarter-mile as you pass. You have the advantage of a flying
start. You run the Vette 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, but you hear a brutal whine that sears your eardrums,
and within three seconds, the dragster catches you and
beats you to the finish line, a quarter-mile from where you
just passed him. From a standing start, the dragster spotted
you 200 mph and not only caught you but nearly blasted
you off the road when he passed you within a mere 1320 feet.

That, my friends, is acceleration!!

via Bandit,

kf6hqc

"

[greenfoam]

And then you pull the engine down and rebuild it because everything is stuffed . They make great power for what they are but the 747 needs to do more than 20 meters down the runway before it falls apart

[tufLTD]

The statistics for these monsters is absolutely amazing. As Jim Read said, "These things can rotate the earth".

[ltd]

Originally Posted by greenfoam

And then you pull the engine down and rebuild it because everything is stuffed . They make great power for what they are but the 747 needs to do more than 20 meters down the runway before it falls apart

He he he

[kircher]

These things are amazing. The sound is even more brutal than the acceleration. If you haven't seen them I recommend you do, and don't use hearing protection for at least one pass.

That's a cheap shot at 747s though, They've been an amazing plane over their long career. Several times they have quickly and safely taken me right across the Pacific.

[FreddyDUZ747]

Walking under the tunnel back in the days of top fuellers(AIR)was a great noise to hear,went straight through ya.

[Paddyboy]

thats bloody amazing!!
I love the corvette bit of info, can you imagine been in that corvette! 200mph is insanely fast, but for a dragster to launch from nothing as you pass and catch up in 4 seconds is mind boggling! The drivers of these cars must have balls!

[Ibrox90]

Originally Posted by Paddyboy

thats bloody amazing!!
I love the corvette bit of info, can you imagine been in that corvette! 200mph is insanely fast, but for a dragster to launch from nothing as you pass and catch up in 4 seconds is mind boggling! The drivers of these cars must have balls!

I reckon the need a certain amount of testicular fortitude. But i think really there just hanging on.

Years ago when i was around 5-7 mum bought me a VHS tape called "And they walked away" it was just filled with american topfuels crashing and flipping.

[BENT_8]

Originally Posted by Paddyboy

thats bloody amazing!!
I love the corvette bit of info, can you imagine been in that corvette! 200mph is insanely fast, but for a dragster to launch from nothing as you pass and catch up in 4 seconds is mind boggling! The drivers of these cars must have balls!

6.3@220+mph on a top fuel bike, now that takes balls!

[Nikked]

Top Fuel dragsters also out accelerate the Apollo rockets don't they?

[Iggypoppin']

Top fuel dragsters are currently the fastest accelerating device built by man. They do out-accelerate rockets, imagine a rocket launching 400m in. 5 seconds, they take longer than that for sure.

[DJM83]

Thats insane

[SSD-85]

Originally Posted by Nikked

Top Fuel dragsters also out accelerate the Apollo rockets don't they?

Correct. But those rockets also produce faaaar more thrust. Plus Top fuellers dont have to try and escape the earths' gravity. The trick is traction, driving rubber to the ground has much better propulsion characteristics than trying to force burning gases through thin air.

[FreddyDUZ747]

http://www.youtube.com/watch?v=2tg6R...eature=related

Side by side mid 4s,one of my favourite 1/4 mile videos.Only goes for a minute max.
http://www.youtube.com/watch?v=rHAZM...eature=related
And heres a little thrust.17 seconds.

[Falcman0o7]

thanks mate. a good read indeed. unreal!!!

[XR Martin]

Yeah but a top fuel engine wouldnt even be able to power the Saturn Vs fuel pumps. (55000hp)

[ltd]

What is with this "mine is bigger than yours" complex?
I get to play with 240,000hp and I think it's a bit sluggish.
What about that dude in the 60's on the rocket sled, didn't he accelerate at something like 10G's, all the way up to over 1000 mph only to meet deceleration of over 45G's; where his retinas detached etc?

[flappist]

Originally Posted by 76txcoupe

Top fuel dragsters are currently the fastest accelerating device built by man. They do out-accelerate rockets, imagine a rocket launching 400m in. 5 seconds, they take longer than that for sure.

Not even remotely close......

[PALE ALE]

Originally Posted by Scotty85

Correct. But those rockets also produce faaaar more thrust. Plus Top fuellers dont have to try and escape the earths' gravity. The trick is traction, driving rubber to the ground has much better propulsion characteristics than trying to force burning gases through thin air.

In a fuel car, you actually want a slight amount of wheel spin to accelerate the car. It needs to "get up on the tyre" (stand up on the tyre, you will see the tyre grow tall). Tuners are looking at the data, and want x amount of wheel speed, at a certain point in the run." its all in the clutch"

A fuel car, has a centrifical clutch (Yamaha pee wee 50) a 3.20:1 diff ratio, and 1:1 direct drive(no gear box). Basically its like taking off in your car in 4/5 gear, and riding/slipping the clutch to get going

Maybe I should start a thread in "Project Cars" on a fuel car. I am part of a fledgeling Fuel Car team here in Adelaide (Scott Ferguson/Gary Evans) But I dont want to go "Blowing our horns" about it, because it may never happen. It has taken an obscene amount of money, blood, sweat and tears to get where we are, and we still have a long way to go yet, and at times things get frustrating and overwhelming and I think we are kidding ourselves, but we havent given up yet.
But just for interests sake, I could take some pictures of the car and various parts and explain how certain things work, some of it is truely mind blowing stuff, and makes any other motorsport look meek

[Fev]

That would be really cool Pale ale! Would be good to see the details and inner workings

[1LOUDXFUTE]

Originally Posted by PALE ALE

But just for interests sake, I could take some pictures of the car and various parts and explain how certain things work, some of it is truely mind blowing stuff, and makes any other motorsport look meek

yes please! :

[Neeek]

Originally Posted by PALE ALE

But just for interests sake, I could take some pictures of the car and various parts and explain how certain things work, some of it is truely mind blowing stuff, and makes any other motorsport look meek

Hell yes!

[Piotr]

In order to exceed 300 mph in 4.5 seconds, dragsters must
accelerate at an average of over 4G’s. In order to reach
200 mph well before half-track, the launch acceleration
approaches 8G’s.

300mph in 4.5second is an average of ~3g not 4g

[sly_ba]

I really do admire the engineering that goes into these cars, however, it makes my mind boggle when I think about all the money and man hours spent on the cars and engines all for the sake of one 4-5 second pass...... Don't get me wrong, I'm a motor sport nut, it just seems like the enjoyment is so short lived for such a massive outlay. Even if it doesn't go bang making a pass (which they do about half the time) they still need to be rebuilt anyway......

[chrisfpv]

Great read, thanks.

[KPOJ]

Awesome read, thanks.