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myvice
7th July 2005, 22:37
I was handed this by a mate who is a drag car fan, I give him endless shit about how cars are so slow ect, my only response was "Well, I'm still faster than YOU"

First some useful? info:
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 consumes 1 gallon of nitromethane per second, a fully loaded 747 consumes jet A1 (fuel) at the same rate with 25% less energy produced.
A stock Dodge 426 Hemi V8 cannot produce enough power to drive the dragster's supercharger.
With 3000 CFM (cubic feet per min) being ramed in by the supercharger on overdrive, the fuel mixture is comperssed into a near solid form befor 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. (cook a chicken REAL fast! mv)
Nitromethane burns yellow, the white flame seen above the stacks at night is raw burning hydrogen, dissociated from atmospheric water vapor by the searing exhaust gasses.
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 1/2 way, the engine is dieseling from compression plus the glow of exaust valves at 1400 deg F, the engine can only be shut down by cutting the fuel off.
If spark momentarily fails early in the run, unburned fuel builds up in the affected cylinders and then explodes with sufficent force to blow cylinder heads off 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 befor half-track acceleration approaches 8G's.
Dragsters reach over 300 miles per hour befor you have completed reading this sentence.
Top Fuel engines turn aproximately 540 revolutions from light to light.
Including the burnout the engine must only survive 900 revolutions under load.
The redline is quite high (for a V8, not your whateverRRRRR mv) at 9500 rpm.
Time for a quarter mile run 4.441 seconds (on 10/05/03 Tony Schumacher)
Top speed is 333.00 mph (533 kph) (on 09/28/03 Doug Kalitta)

The bottom line, assuming evrything is paid off, the crew worked for free (crews get PAID now? mv) and nothing blows up, each run costs aprox $1000.00 per second. (Thats U.S. $ too. mv)

What this means to us:
You are riding the avarage (your choice here) MotoGP bike. Over a mile up the road , a Top Fuel dragster is staged and ready to launch down a 1/4 mile strip as you pass.
You have the advantage of a flying start.
You run your bike hard up through the gears and blast over the starting line at honest 200 mph (923 ft/sec) or (320 kph) (YAAFUCKINGHOOO! mv)
The "tree" goes green for both you and the dragster 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 beat you to the finish line, a quarter of a mile away from where you just passed him.
Think about this, from a standing start, the dragster had spotted you at 200 mph and not only caught you, but nearly blasted you off the track when he passed you within a mere 1320 foot long course!

Sucks eh? We need faster bikes!
We do have advantages though, we can go around corners and thay aren't using them as pursuit cars yet.
It took me ages to type this so you had better have appreciated it!
I'm a bloody mechanic, not a typist!

Patch
7th July 2005, 22:41
Fuckin impressed at the stats bro. Typing ain't bad either :yes:

Bikes are still cooler. :Punk:

boomer
7th July 2005, 22:47
i'm sure having your head pinned to the headrest/rollcage will bring a healthy grin to your boat race :devil2:

Pixie
7th July 2005, 22:49
I also remember some figure given for the thrust of the exhaust gasses exiting the pipes being quite incredible,can't remember the figure, but with 3000 cfm going in and then coming out hot you get the idea.
Although the thrust is directed upwards.

XP@
7th July 2005, 22:51
Just ask him what happens when he gets to a corner.
And how easy are they to park.

GROOMER
7th July 2005, 23:00
This looks very much copied from a page linked from a KB thread that I read the other day, hmmmmm.... :whistle:

FROSTY
7th July 2005, 23:01
lets see the bugger get the dragsgter round a corner--and then casually lean in and say--ok bud--best outa 3 hu--and fuck off at 200km/h -wait the half hour itll take him to turn round

Patch
7th July 2005, 23:12
This looks very much copied from a page linked from a KB thread that I read the other day, hmmmmm.... :whistle:
Perhaps Pure acceleration 27th February 2005, 17:18

cheeky li'l fucka :nono: :nono:

Toast
7th July 2005, 23:57
Sorry, if the bike starts at 200mph, or 923 ft/sec, won't he finish before the dragster catches him? (given the course is 1320 ft long)

Thank God that the wildly inefficient 747 is somewhat more reliable for that extra 25% of juice it uses.

onearmedbandit
8th July 2005, 00:33
Yup, somethings not quite right there. The rest of it is interesting reading though.

riffer
8th July 2005, 09:55
Isn't a mile approx 5280 feet?

Therefore 200mph is 105600 fph.

Divide by 3600 = 293.3333333 feet per second.

That's how the dragster goes past you.

It takes 4.5 seconds to do the quarter mile at 200mph.

QED

vifferman
8th July 2005, 10:00
This looks very much copied from a page linked from a KB thread that I read the other day, hmmmmm.... :whistle:
I first read it last year (?) on the Aussie VFR forum. There's a guy on there who posted it - he works for a drag racing team; each guy has a specific job, and he is in charge of supercharger belts (and other things if required).
One interesting thing missed out - on nitromethane, the tuning is back to front; if the engine's running too lean, they pump less fuel in, and if it's too rich, more fuel.

bugjuice
8th July 2005, 10:08
nice readin..
no mention on the deafening sound they make too..

I also watched a doco on drag cars, they rebuild from the sump up virtually every drag. An engine that lasts ~15 seconds.. The amount of pressure those things build up is unreal

White trash
8th July 2005, 10:11
Isn't a mile approx 5280 feet?

Therefore 200mph is 105600 fph.

Divide by 3600 = 293.3333333 feet per second.

That's how the dragster goes past you.

It takes 4.5 seconds to do the quarter mile at 200mph.

QED

Good calculating grasshopper. Top fuel dragsters are now topping 325mph on a good pass.

0 to 500kph in 4 seconds. Gimme the keys!

ManDownUnder
8th July 2005, 11:23
yeah... but with the price of fuel and all - I think I'll stay on the RF.

Thanks anyway

Lou Girardin
8th July 2005, 11:42
Nip up to the shops - engine rebuild. Forget the milk, go again - engine rebuild.
Go to work - engine rebuild.
Nah! I'll stick to a slow bike thanks.

That Guy
8th July 2005, 11:46
Isn't there a fact too that under load the crank shaft twists so much they have to delay the spark ignition progressively down each cylinder bank because the pistons arive at TDC later than they should because of the twisting.

FEINT
8th July 2005, 11:55
I will beat him to the DRAGs and home again hehehhee :devil2:

bear
8th July 2005, 11:55
At the end of the day, it's not apples for apples though is it. Wouldn't you be better off comparing a GP/SBK bike to an F1 car, or the like, if you were interested in the bike/car debate?

vifferman
8th July 2005, 11:59
Isn't there a fact too that under load the crank shaft twists so much they have to delay the spark ignition progressively down each cylinder bank because the pistons arive at TDC later than they should because of the twisting.
Yeah, although IIRC, the Ozzie drag guy I was talking about said summat about a split crank, as there is so much whip is so much that they break anyway.

scumdog
8th July 2005, 12:01
At the end of the day, it's not apples for apples though is it. Wouldn't you be better off comparing a GP/SBK bike to an F1 car, or the like, if you were interested in the bike/car debate?

Yeah but it WAS interesting reading.

I get guys saying how much faster their *bike is than my truck, I like winding them up by offering to race them - and each of us has to carry a load of 50 dozen beer in crates......
*Works with guys with Evos/WRX whatever.

vifferman
8th July 2005, 12:19
I get guys saying how much faster their *bike is than my truck, I like winding them up by offering to race them - and each of us has to carry a load of 50 dozen beer in crates......
*Works with guys with Evos/WRX whatever.
:rofl:
That's a bit more inventive / practical than, "Yeah, but my dick is bigger than yours!"

Flyingpony
8th July 2005, 12:38
they rebuild from the sump up virtually every drag. An engine that lasts ~15 seconds..
Those engines have a very short stressful life. Thought they'd be good for more than just one dash. :whistle:
Man, those dragster places must have engine block coffee tables pouring out of their ears! :love:



Nip up to the shops - engine rebuild. Forget the milk, go again - engine rebuild.
Go to work - engine rebuild.

:rofl: :rofl: :rofl: (I was thinking the same).
And that's even assuming you can make it. Engines are only good for maybe 1/2 mile.

ManDownUnder
8th July 2005, 12:45
:rofl:
That's a bit more inventive / practical than, "Yeah, but my dick is bigger than yours!"

AGREED! Only lost than one twice from all 5,498 guys competing agin me...

Got really boring.

BJ and Biff are two names that come to mind for some reason...

Lou Girardin
8th July 2005, 14:34
AGREED! Only lost than one twice from all 5,498 guys competing agin me...

Got really boring.

BJ and Biff are two names that come to mind for some reason...

The mental image conjured up is very disturbing. How did you measure them, hand widths?

ManDownUnder
8th July 2005, 15:19
The mental image conjured up is very disturbing. How did you measure them, hand widths?

Head thickness... why do you ask?:rofl:

myvice
9th July 2005, 18:51
This looks very much copied from a page linked from a KB thread that I read the other day, hmmmmm.... :whistle:
You mean I typed this out for NOTHING?
Well, it will improve my typing skills if nothing else, I was aware that it came off the net but didnt know where to find it.
Or how to link it/transfer it to this site even if I found it, must learn how one day... Will put it on my to do list... yeah right!

WINJA
9th July 2005, 19:06
FUCK YEAH I DONT LIKE THE DRAGS BUT ID GO TO SEE THOSE SORT OF CARS DO THE 1/4 MILE.
LAST TIME I WENT TO THE DRAGS THE PAC ROTARY RACING TEAM WAS HERE FROM AUSSIE FAST ROTORS BUT ONLY PULLING 1 MPH HIGHER TERMINAL THAN ME DOWN MERE MERE BUT THEY WERE 3 SECONDS FASTER .
THROW IN SOME CORNERS AND ILL LEARN THEM

speedpro
9th July 2005, 23:35
I've heard that the nitro motors are looking at 8,000hp now. 1,000hp per cylinder. 16hp per cu".

The amount the big end bearing shells were squished out was a measure of how well the cylinder was running.

I can't imagine the cranks those things run being flexed substantially, but I could be wrong.

erik
10th July 2005, 01:14
You mean I typed this out for NOTHING?
Well, it will improve my typing skills if nothing else, I was aware that it came off the net but didnt know where to find it.
Or how to link it/transfer it to this site even if I found it, must learn how one day... Will put it on my to do list... yeah right!

Go to www.google.com

type in a few words from the text your looking for eg

"Top Fuel dragster 500 cubic inch Hemi engine makes more"

(you can try it with or without the quotation marks, sometimes it'll work better one way or the other)

Click "Search".

Works for other stuff too, eg song lyrics - type in a few words you can remember (with or without quotation marks, try both. plus adding "lyrics" helps sometimes) and search for it.

To transfer it here, highlight the text and copy and paste it.

Brian d marge
10th July 2005, 01:34
I can't imagine the cranks those things run being flexed substantially, but I could be wrong.
Even a fizzee fifty crank does the wild thing , it coils up unwinds , bends ,,u name it it does it....
Then some loony adds 7995 more horse power ......cranks are amazing bit of kit!

Another 0.002 cents worth invested in the family fortune!
Stephen