1/4 Mile Info That May Surprise You

[scientific steve]

Seen this on another forum and thought that it could be and interesting read for our 1/4 mile folk

LESSON IN ACCELERATION -

* One Top Fuel dragster 500 cubic inch Hemi engine makes more horsepower than the first 4 rows at the Indy. 500.

* Under full throttle, a Top Fuel dragster engine consumes 1 gallon of nitromethane 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 nitromethane the flame front temperature measures 7050 degrees F, 3800 degrees C.

* Nitromethane 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 ½ way, the engine is dieseling from compression plus the glow of exhaust valves at 1400 degrees F. The engine can only be shut down by cutting off 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 the 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 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 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 (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).

If that hasn't made you think enough, let's put all of this into perspective:

You are riding the average $250,000 Honda MotoGP bike - a seriously fast machine. 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 RC211V hard up through the gears and blast across the starting line and past the dragster at an honest 200 mph (293 ft/sec). The 'tree' goes green for both of you at that moment. The dragster launches and starts after you. You keep your wrist cranked 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 the standing start, the dragster had a 200mph disadvantage, and not only caught, but nearly blasted you off the road when he passed you within a mere 1320 foot long drag strip.

Now tell me the straight line racing is boring!

[psyweb]

I love this stuff, really goes to show how advanced those things are.

But having said that, 4 doors and a boot does go a long way :-)

[craigdmcd]

Yep, absolutely fantastic figures, but how well does it get round the first corner (never mind the following twelve that make a track) - there is more to speed than straight lines.

[st3ph3n]

I do enjoy the drag racing. More from the technical perspective than the racing I suppose. I'm a big fan of the "golden era" stuff. People like Big Daddy Don Garlits. But then that's harking back to the hot rod scene too, and then that veers off into my love of the land speed record race of the 60 with the Arfons brothers, Craig Breedlove etc.

[scientific steve]

Yep, absolutely fantastic figures, but how well does it get round the first corner (never mind the following twelve that make a track) - there is more to speed than straight lines.

I'm still trying to figure out your response to this, I mentioned in the title that it was for "Our 1/4 mile folk"

And if you have a wee look here

http://forums.sidc.co.uk/index.php?showtop...0&start=720

You can see that there is quite a few folk from here that do go on the 1/4 mile and therefore may be interested in this kind of stuff.

The figures quoted will do bu&&er all for getting you round a corner but thats not the point.

Yes, there is more to speed than straight lines but if you do go bloody fast in them then you have a better chance of being first dont you

Is there not some chap for the Edinburgh area that does these 1/4 mile thingys AND can do corners too

Stephen

Yep, hats off to them folks, big respect for what they got up to

[RATechnology]

I have to admit coming from Australia where cubic inches matter and 1/4 mile times are a big deal, watching a top fuel event is one of the most impressive sights (and Sounds) you'll ever see.

A ex work mate, engineers a top fuel car! Had probably the most interesting conversation with him about these rather than what we both should have been doing at the time was talking WRC!!! (we were on a rally at the time)

A simple adjustment of ignition or fuel, can gain or lose 500BHP! in order to gain vital traction! It's the only motorsport that is completely unrestricted.. When you sit and chat to someone like this about Top Fuel it gives a better understanding and it's impressive!

[craigdmcd]

Steve, you are absolutely right, and the first corner is completely irrelevant to these vehicles, but then so is comparing a MotoGP bike's ability to one of these beasts.

The headline facts on these cars are quite incredible, but some of the headlines are like some in papers - designed to make them look good.

And yes, I do appreciate that AndyF is quite handy round the corners as well as n a straight line, but in his line of work, it is good to help your business with weekend's that will promote your living.

[scientific steve]

Why is comparing a Moto GP bike to a Top Fuel Dragster completely irrelevant?

Would it be better to compare it to a Touring Car so it looks even better for them Jade Goody grabbing headlines?

No, I don’t think that would be fair.

The comparison was to give a fair indication of the amount of acceleration involved and with the GP bikes going about the same speeds as the F1 cars (not around corners that is) but without the protection, also hints of the dangers involved to the drivers.

[craigdmcd]

* Under full throttle, a Top Fuel dragster engine consumes 1 gallon of nitromethane per second; a fully loaded 747 consumes jet fuel at the same rate with 25% less energy being produced.

Easy to pick on an old design engine - try something from a 777 or one of the latest Airbus range and I'm sure the outcome would be different. But even still, I think each jet on a 747 produces 70,000hp of thrust if what I read somewhere is correct - I'm sure one of the boys that work in Glasgow Aiport Engineering would be able to correct me on this.

* Spark plug electrodes are totally consumed during a pass. After ½ way, the engine is dieseling from compression plus the glow of exhaust valves at 1400 degrees F. The engine can only be shut down by cutting off the fuel flow.

To me this shows that they are only getting the best of the run for the first 1/8th of a mile, because as soon as you start dieseling, you are not running correctly

If that hasn't made you think enough, let's put all of this into perspective:

You are riding the average $250,000 Honda MotoGP bike - a seriously fast machine. 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 RC211V hard up through the gears and blast across the starting line and past the dragster at an honest 200 mph (293 ft/sec). The 'tree' goes green for both of you at that moment. The dragster launches and starts after you. You keep your wrist cranked 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 the standing start, the dragster had a 200mph disadvantage, and not only caught, but nearly blasted you off the road when he passed you within a mere 1320 foot long drag strip.

Now tell me the straight line racing is boring!

Now lets work this one out

200mph on the bike equates to 3.33miles per minute.

3.33mpm equates to 5860.8 yards per minute

5860.8 yards per minute equates to 17582.4 feet per minute

17582.4 fpm is 293.04 feet per second

A best ever 1/4 mile time is 4.41 seconds - so the Honda has covered 1292 feet of the 1320 feet (1/4 mile) in that time.

So the drag racer was still a good way back at the 3 second mark - this makes this fact a lie.

Quite possibly this is why they chose a 200mph MotoGP bike, and not a 220mph F1 car, a 230mph LeMans racer or a Bugatti Veyron, because the drag car wouldn't have beaten any of these in it's theoretical standing start race.

Like I say, headline facts always look good until you check them out.

They are still immensly scary cars though

[scientific steve]

Like I say, headline facts always look good until you check them out.

They are still immensly scary cars though

and I thought that I had too much time on my hands

[craigdmcd]

and I thought that I had too much time on my hands

I was always really fast on mental arithmetic, in fact if I had been as quick on a kart track as I was at numbers I would have won the Scottish TKM Championship instead of being third