Drag Racing Question

[PECivil]

I watched the Drag Racing @ Englishtown this weekend but there was something I didn't quite get...

everyonce in a while the winning driver had a SLOWER et than the losing driver.....

The announcers called it a "holeshot" victory??

splain, lucy, splain

does it have to do with how they stage?

BTW those top fuel dragsters are really really bitchen

I am going to go the next winternationals at Pomona

I need to hear those engines in person

thanks!!

[SilverStreak]

That means the race-winner crossed the line first, which means his R/T (reaction time) was quicker.

ET (Elapsed time) measures from the moment of each driver's launch to the finish line. The ET measures the elapsed time "after" the R/T, so to speak.

For example, say the guy in Lane A ran an 11.7, and the guy in Lane B ran an 11.8.

But the guy in Lane A, his R/T was a .650. The R/T of the guy in Lane B was .500.

Lane A: 11.7 + .650 = 12.35
Lane B: 11.8 + .500 = 12.30

Lane B is the winner cuz he would have crossed the line first. That 12.30 includes the R/T, so to speak, cuz it started ticking when the Green hit.

Does that make any sense, or did I further muddy those waters???

[PECivil]

so the et they give at the end doesnt include the reaction time...

and it starts when the car starts moving NOT when the light turns green

so if a driver gets off a faster R/T he can have a longer ET but still win because he crossed the line first and his OVERALL time from green light to crossing the line is faster, even if his et wasn't

that makes sense (assuming I got what you said right?)

so the ET they show at the end ISNT the total time it took from green to the end

its just the time from when they started moving to the end

why do they do this? perhaps to make the ET number be independent of the driver's R/T compairs the cars better?

Thanks silver!! appreciate the info.

[Dark Helmet]

you are exactly right PE... now, we can talk about red-lighting and busting-out.... or not.

[PECivil]

thanks guys! I am a drag newbie but I have been watching it on tv and it looks quite bitchen!!

I want to go and see it in person

ok ok more questions

what makes the speed hierarchy

ie prostock ets 6.7 funny cars ets 4.9 top fuel ets 4.5

is it engine size, kind of gas they run?? what is the differences in the cars? they all look like big block V-8's with superchargers

whats up with the "Staging duels" why do they do that?
whats the advantage in staging last vs first?

what kind of torque/hp numbers on the top fuel dragsters?

you gotta love how they literally take the engine apart between races those crew guys are good! what pressure to be under

thanks for answering the newbie questions!!

[Ken ///M3]

is it engine size ?

Actually, all of the "pro" classes (i.e. Pro Stock, Funny Car, Fuel dragster) run the same size engine, 500 C.I. Some teams "play" with a slightly smaller displacement, but the max is 500 C.I.

kind of gas they run?

Pro Stock cars must use "pump" gas but the octance is around 118. They also must run 4 BBL cars (2), no electronic fuel injection or turbos, superchargers, NOS... They put out about 1200 HP and use manually shifted 5 speed clutchless transmissions. The multi-disc clutch is only used to launch the start.

what is the differences in the cars? they all look like big block V-8's with superchargers?

Funny cars and Fuel dragsters use basically the same engines. 500 C.I. max, 90%/10% Nitromethane/alky fuel, a supercharger that spins 20% to 40% overdrive off the crank, 2 spark plugs per cylinder from twin magnetos that crank out 80,000 volts each plug. There are 4 levels of mechanical fuel injection, controlled by air timers, and a multi-disc clutch that is controlled by weights for the initial launch and air timers for traction control during the run. They have no transmission (except for a reverser for the burn out) all the traction control is done by clutch slippage and fuel/ignition management under command of air-driven timers. There are some significant fuel utilization model differences between dragsters and funny cars, but the driven train is pretty much the same, except that dragsters are rear engined. Wheelbase for dragsters is 300 inches and funny cars is 125 inches.


whats up with the "Staging duels" why do they do that?

Sometimes these are just to detract the other drivers attention but the fuel cars (i.e. dragsters and funny cars) are heating up like crazy at idle and burning lots of fuel. A long stage battle can mean a fried engine and/or a serious wheel stand. Most starters won't put up with this crap and some times just hit the go button or shut them off.

whats the advantage in staging last vs first? None that I ever felt worked.

what kind of torque/hp numbers on the top fuel dragsters?

There's really no dyno that can take the HP of a fuel motor and generally the engines don't last long enough for a full pull. From the math of getting a particular weight and aero package done the quarter at 4.55 second and 325 MPH, the numbers are about 7,000 HP and same for torque. Amazing stuff.

BTW, each run consumes about 12 gallon of fuel, and if nothing breaks the consumables run $4000 to $6000 per run. Hope this helps, try NHRA.com.

Ken

[MauiM3Mania]

Fuel cars are amazing indeed! -Scott

[PECivil]

those stats are truly amazing

7000hp!! my god

what it must feel like to make a run in one

[Ken ///M3]

No problerm, glad to help. I'm an ex-drag racer, and still keep current with the technology.

BTW, the driver of the black Cope Car, Ron Capps, is a good friend. My wife and I are kinda Aunt and Uncle for their 2 kids. We just got back from a trip to Vegas with them for the NHRA race. Great people.

Just a few interesting notes:

The g-forces are about 4-5 Gs during the run and over 7 Gs as the chutes come out. That's about 2X the G forces compared to a carrier F14 launch.

At the 60ft mark, fuel cars are going over 100 MPH in about 8/10ths of a second. So when we brag about our M3 0-60 in 5.5 secs, a fuel car driver has the chutes out and is looking for the turn off signalman.

By half track at 660ft, fuel cars have attained 250 - 280 MPH and are still pulling like hell. However, it's at the 660ft mark that aerodynamic factors take over and the cars run into a "wall" and only pick up an additional 50 - 70 MPH. The large wing on the top fuel dragsters, that is 7 ft off the track in the "clean air", creates over 6,000 lbs of downforce on those big Goodyear "slicks" and the cars can still spin the tires at the top end.

When watching a fuel car run, closely focus on the exhaust headers. Sometime you'll see a pipe change to a solid liquid mist when that "hole" is no longer firing. This isn't too bad for dragsters, but for funny cars the sudden imbalance of side thrust from the exhaust will steer the car to one side or the other, and sometimes the "hole" comes back and the driver is cranking that little wheel for all he's worth.

What's it feel like ? My experience was from a long time ago and about 1/2 of today's power levels. Basically, it feels like someone kicked you in the ass real hard only it lasts for 5 seconds. The shaking and noise no one every gets used to and you can feel the tires "grow" as the run progesses. You swear to yourself that you will never get back in that seat again, then you ask "did I win?"

Ken

[MauiM3Mania]

Ken,

Ron wouldn't remember me, but I *think* that event was his first win in a funny car (after switching from top fuel?). GIR in St. Louis, 1997ish. We e-mailed back and forth briefly as I recall. Decent guy, for sure.

Here's a another shot where loads of fuel didn't ignite. It's a burnout, night session, same event. -Scott

[99blackbird]

If I inderstand correctly, these motors have hemi-style heads and completely destroy the spark plugs by the 1/8 mile leaving only the heat of the combustion chamber to detonate the fuel mixture.

[Ken ///M3]

An old "wives tale". The plugs (2 per cylinder) are usually intact at the end of the run. Having just the heat in the combustion chamber do the ignition would lead to some spectacular explosions as the uncontrolled flame is allowed to "escape" into the intake manifold and blower. This happens sometimes, but not very often these days.

Toward the end of the run, the crew chief has made adjustments to the fuel system to actually "lean out" the engine a little, a condition nitro motors like. Also he takes some out of the "lead" in the mags to protect the engine. The driver has no control of these actions, he's just holding the pedal down. This is all done with air timers as electronic control is against the NHRA rules. Another dumb NHRA decision made 20 years ago an never updated.

Ken