Acceleration

[John Soliday]

I learned something at the Boulder County Tractor pulls too.  The heavily
modified turbodiesels run 125psi of boost compared to 24psi for a stock
tractor. 

-----Original Message-----
From: David Beard [mailto:davidebeard at comcast.net] 
Sent: Friday, August 10, 2007 7:06 AM
To: GPZLIST
Subject: Acceleration

Thought some of you guys might find this interesting...

Dave B

Acceleration; Put Into Perspective

*   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 dragster engine consumes 11.2 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 Hemi V8 engine cannot produce enough power to merely 
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 1/2 
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 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
cylinder heads off the block in pieces or split the block in half.

*   Dragsters reach over 300 MPH before you have completed reading this 
sentence.

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

*   Top Fuel engines turn approximately 540 revolutions from light to 
light!

*   Including the burnout, the engine must only survive 900 revolutions 
under load.

*   The redline is actually quite high at 9500 RPM.

*   THE BOTTOM LINE:  Assuming all the equipment is paid off, the crew 
worked for free, & for once, NOTHING BLOWS UP, each run costs an estimated
$1,000 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).

*_Putting this all into perspective:_*

You are driving the average $140,000 Lingenfelter twin-turbo powered
Corvette Z06.  Over a mile up the road, a Top Fuel dragster is staged &
ready to launch down a quarter-mile strip as you pass.  You have the
advantage of a flying start.  You run the 'Vette hard up through the gears
and blast across the starting line & pass the dragster at an honest 200 MPH.
The 'tree' goes green for both of you at that moment.

The dragster launches & starts after you.  You keep your foot down hard, but
you hear an incredibly brutal whine that sears your eardrums & within 3
seconds the dragster catches & passes you.  He beats you to the finish line,
a quarter-mile away from where you just passed him.  Think about it - from a
standing start, the dragster had spotted you 200 MPH & not only caught, but
nearly blasted you off the road when he passed you within a mere 1320 foot
long race!

That, is acceleration!