Pretty interesting.This is some crazy info on dragsters I wonder if it is all true...

* One dragster's 500-inch Hemi makes more horsepower then the first 8 rows at Daytona

* Under full throttle, a dragster engine consumes 1 1/2 gallons of nitro per second, the same rate of fuel consumption as a fully loaded 747 but
with 4 times the energy volume.
* The supercharger takes more power to drive then a stock hemi makes.

* Even with nearly 3000 CFM of air being rammed in by the supercharger on overdrive, the fuel mixture is compressed into nearly-solid form before
ignition. Cylinders run on the verge of hydraulic lock.

* Dual magnetos apply 44 amps to each spark plug. This is the output of an arc welder in each cylinder.

* At stoichiometric (exact) 1.7:1 air/fuel mixture (for nitro), the flame front of nitromethane measures 7050 degrees F.

* Nitromethane 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.

* 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 of it's fuel flow.

* if spark momentarily fails early in the run, unburned nitro builds up in those cylinders and then explodes with a force that can blow cylinder
heads off the block in pieces or blow the block in half.

* Dragsters twist the crank (torsionally) so far (20 degrees in the big end of the track) that sometimes cam lobes are ground offset from front to
rear to re-phase the valve timing somewhere closer to synchronization with the pistons.

* To exceed 300mph in 4.5 seconds dragsters must accelerate at an average of over 4G's. But in reaching 200 mph well before 1/2 track, launch
acceleration is closer to 8G's.

* If all the equipment is paid off, the crew worked for free, and for once NOTHING BLOWS UP, each run costs $1000.00 per second.

* Dragsters reach over 300 miles per hour before you have read this sentence.

 

:eek: :cool:

 

I make it to somewhere around 60-65 mph :D

Beach

 

Here's one that always gets me thinking: Dragsters 1/8 mile speed is 270ish mph, they only gain ~ 50 mph in the second half of a quarter mile run.

Think about this and then you can see why I am looking forward to seeing dragsters achieve 300 mph in the 1/8 mile - where it will go from there is anyone's guess. Don't say it can't be done, remember that when dragracing was in its professional infancy there were degreed engineers who proclaimed 150 mph in the 1/4 mile to be the limit for dragsters.

Thomas

 

I can attest to the nitro burning yellow..... Not a cloud you want to be in very long. Stuff tastes like crap too!!

 

neat email. Guess those dragsters would not be good daily drivers ;) They are lucky if they make it down the track without smoken the tires.

 

60? Between my reaction time and spinning I am still trying to get to the 60' mark. :lol:

 

Sounds about true to me.

The figures that NHRA spouts off all the time are that the motors make about 6000 HP and it takes 750 HP to turn the blower!

I thought the flames were from unburnt fuel though. I thought that Nitro has an extremely slow burn rate. This explains the flames and why the Nitro cars are so much louder than an Alcohol car.

 

Yup.. I agree, I do know Nitro burns very slow, & thats why you see flames, however I didn't know that was why the Nitro cars were so much louder, but it makes sense to me..

 

Actually, our Nostalgia Top Fuel car will put out about 3000 hp, whereas the NHRA cars are putting out closer to 6000. The flames coming out of the headers are the result of fuel being burned as it leaves the cylinder. The motor is not very efficient, and it only burns I've heard, around 60% of the fuel that is supplied. If you stand next to some Top Fuel motors, you can see/feel the raw fuel coming out of the headers sometimes. Yes, nitromethane does burn fairly slowly.

With regard to the 'loudness', the next time you are at the races around the Top Fuel cars, listen for when the tuner will switch from alcohol to the alcohol/nitormethane mixture. The motor is typically started on alcohol to put some heat into the motor, and then then it is switched over to nitromethane/alcohol mixture. There is a definite difference in the audible level. Nitromethane actually has oxyen within its chemical compound and will use this to burn even more nitromethane. This increase in burn translates to more horsepower and is part of the reason for the increase in 'loudness'.


[Modified by shamvette, 2:47 AM 7/24/2002]


[Modified by shamvette, 3:36 AM 7/24/2002]

 

Sham....

>>"Actually, our Nostalgia Top Fuel car will put out about 6000 hp, whereas the NHRA cars are putting out closer to 9000. "<<

I was just wondering how you or NHRA come up with those #s .. I know they cant dyno those motors, & the ET & mph they run are traction limited.. I think all or most good T/F cars are backing off with the clutch, timing advance ..etc in order to stay hooked up..

 

It is somewhat of a guestimate! There are estimation calculations that will give a reasonable estimate of the hp. We have a g-meter on the car, as well as rpm sensors on the engine and drive shaft. We of course know the weight of the car, time it takes to get from point a to b, as well as the tire size. We even know exactly what point the car is 1 to 1, or where the clutch is no longer slipping. I have never worked through all of the calulations personally, and my numbers on the nostalgia and NHRA cars should have been 3000 and 6000, respectively. (Brain fade for a minute!!)

Our biggest challenge is getting the 3000 hp to provide traction on a 12 inch wide tire, as opposed to the NHRA tires that are I believe close to 17 inches wide. We have way more horsepower than we can really put to the track. Quite a few of the drivers proved this just this past weekend in Sacramento (WCTA Nostalgia Drag Race).

 

:cool:

 

:eek: :cool: