I spent the day at the Winter Nationals yesterday on a job. That was enough drag racing and inhaled toxins to last me a while. I am not itching to go back (unless I'm getting paid to do so) but I did learn a few things:

• Current top fuel cars make about 8000hp and burn between 75-80 gallons of fuel per run.

• Crank case breathers feed into a 5 gallon catch can. It is half full after one pass.

• When two top fuel cars leave the line together, it measures 2.5 on the Richter scale.

• Teams wait until just before their qualifying session to assemble the engine: they tune for weather & track conditions with different thickness head gaskets that change compression. The head gaskets they use for tuning are sized in .001" increments!

• Top fuel cars do not use multi-geared transmissions. They are direct drive and use a multi-plate centrifugal clutch just like a go-kart. NHRA mandates a 8250rpm redline. So they leave the line at 8250rpm and by the time they reach the finish (about 4.5 seconds later) the clutch and aero-drag "slows" the engine down to about 7000rpm at 330mph.

• It takes 1000hp just to move the rear wing thru the air at 330mph

• Initial spark advance is set at 53 degrees before TDC. (The fuel burns a lot slower than gas and the combustion chambers are nearly the size of my attic...)

• There is a wheel speed sensor on the left front wheel. One of their tuning guides is reading the length of time it is off he ground from due to the torque and flex of the chassis.

• One chassis is good for 100 runs until it is retired.

• Listening to Tony Schumacher give a motivational speech before a couple hundred new army recruits, I had a lump in my throat and was ready to enlist myself. The US Army is getting every penny's worth from drag racing.

But all the money and effort involved to get that 4.5 second rush has got to make drag racing the worst bang for the buck in all of motor sports. Impressed I was. Envious, I was not.

Running Hondas in NASA is much cheaper, far quieter, smells a whole lot better.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thawley &raquo;</TD></TR><TR><TD CLASS="quote">Running Hondas in NASA ... smells a whole lot better.</TD></TR></TABLE>

Racing is like cheese. One man's Camembert is another man's rotten milk.

 

i was upset to see that only on of the cars my uncle works on made it into the the top 16

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thawley &raquo;</TD></TR><TR><TD CLASS="quote">
• Current top fuel cars make about 8000hp and burn between 75-80 gallons of fuel per run.</TD></TR></TABLE>

They don't burn that much fuel! It's closer to 12-15 gallons per pass. Maybe 75-80 gallons per race day?

 

Amazing...

Can one of you math wizzes figure this out for me

Total revs per Top Fuel run 8,000RPM x 4.7sec = ?

Rev per foot at 330 MPH

In other words at that kind of speed how far does each fire of a plug move the car?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thawley &raquo;</TD></TR><TR><TD CLASS="quote">
• Top fuel cars do not use multi-geared transmissions. They are direct drive and use a multi-plate centrifugal clutch just like a go-kart. NHRA mandates a 8250rpm redline. So they leave the line at 8250rpm and by the time they reach the finish (about 4.5 seconds later) the clutch and aero-drag "slows" the engine down to about 7000rpm at 330mph.
.</TD></TR></TABLE>


Its a lot more complicated then a go car though. they use air to engage each clutch disc as a certain time down the track.

 

Top fuel is fun, but Pro Stock and Comp is where it is at.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by slammed_93_hatch &raquo;</TD></TR><TR><TD CLASS="quote">


Its a lot more complicated then a go car though. they use air to engage each clutch disc as a certain time down the track.</TD></TR></TABLE>

Damn! I can't imagine what kind of temps those discs reach in a matter of seconds

 

I was at the event also. I love going to the top fuel drags to watch the pit crews and to witness the birth of a 8,000hp machine. Its very interesting to read about the specs and physics behind the cars.

Here is an interesting number it takes 14.6Kg of air to burn 1Kg of gasoline, but with nitromethane it takes 1.7Kg to burn 1Kg. Nitromethane actually contains its own oxygen.

Julian