[Non P-car] Acceleration

rennch · rennch's Garage

Thought this was cool.

A lesson in acceleration:

First, some useful info:

*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 1/2 gallons 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 measure 7050 degrees F.

*Nitromethane burns yellow. The spectacular white flame seen above the
stacks at night if 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.

*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
per second. The current Top Fuel dragster elapsed time record is 4.441
seconds for the quarter mile (10/5/03, Tony Schumacher.) The top speed
record is 333.00 mph (533 km/h) as measured over the last 66' of the run
(9/28/03 Doug Kalitta.)

Putting all this into perspective:

You are riding the average $250,000 Honda Moto GP bike. 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 the throttle hard open, 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.

Think about it, from a standing start the dragster had spotted you 200 mph
and not only caught, but nearly blasted you off the road when he passed you
within a mere 1320 foot long race course.

That folks, is acceleration!