This puts raw acceleration into perspective!

[URY914]

I don't think it is really driving. More like just holding on.

I respect the cars mechanically but driving them would not be the same as a road race car or a/x to me. People say a/x is more waiting than driving. If I get 4 runs at a minute a piece in a day I'm happy. Some of these guys won't run a minute all weekend even in the slower classes. It's not for me.

[Rick V]

Originally Posted by URY914

I don't think it is really driving. More like just holding on.

I respect the cars mechanically but driving them would not be the same as a road race car or a/x to me. People say a/x is more waiting than driving. If I get 4 runs at a minute a piece in a day I'm happy. Some of these guys won't run a minute all weekend even in the slower classes. It's not for me.

I don't know about that. If you have ever payed attention to what these people do just to go straight and the "peddeling" that is required to get down the track. It is very impressive. Just like any type of racing, there is a talent that is required, and to be able to handle that type of power is just awsome. These drivers have reaction times (while driving not cutting lights) that make my cats sit up and say damn.
And Ashley Force is cute

[sammyg2]

Top fuel cars have a fuel pump shut off valve next to the steering wheel. It leans out the engine enough to kill it at the end of the run.

I built a flatbottom drag boat when i was 22 years old and had more money than brains. After blowing up two motors on methanol, I decided it would be a really good idea to step up to nitro. Someone should have slapped me. Where were you guys then?

After half a season I was broke (and so was the boat) and had 3 credit cards maxxed out and my girlfriend left. But it was cool

[Jeff Higgins]

Actually Sammy, it's a throttle shut-off that returns the butterflies to the idle position up against their stop. The fuel pump is mechanically driven off the front of the camshaft and cannot be shut off; if the motor is turning, the pump is turning.

[Mule]

Originally Posted by don911

The raw power of top fuel drag racing is so over the top that it's hard to believe that's it's even possible to harness that amount of energy. Technically, it's an interesting sport but watching is so boring in my opinion. I occationally can sit through short highlights but nothing more.

Go see it in person. If it doesn't make your hear pump, call your doctor.

[Mule]

Originally Posted by Jeff Higgins

The part about shutting off fuel flow to cut the engine is kinda sorta true. Problem is, the driver cannot do it. The NHRA does not allow fuel control valves, nor levers to control them, in the cockpit for safety reasons. The motors run on mags and again, there is no driver accesible shut off. A crew member has to shut the car off. In the case of an aborted run, keep your eyes on the guy that walks up and shuts it off. At the end of the run, it just runs out of fuel somewhere in the shutdown area. You will see these cars wreck sometimes and rather inexplicably (seemingly) just keep running. I saw a top fuel car flop on its side after getting crossed up right out of the hole one day; it kept spinning like a top around the rear tire that was on the ground. No way to stop it; the driver just had to wait for it to run out of gas.

Jeff, they absolutely control the fuel from the cockpit. When they pre-stage the car, the clutch is out. They move a lever to engage the second stage of the fuel pumps (you can hear the difference in the engine). Next it's stomp the gas pedal, steer like hell, let off, hit the parachute release, hit the fuel shutoff, breathe. If they ran out of fuel at wot they would grenade the engine every run. And I agree, I don't think they diesel. I think spark is very accurately controlled.

[Jeff Higgins]

I stand corrected, Mule. The car that I was helping with had nothing like that, though. There was, quite literally, nothing in the reach of the driver to control fuel or ignition. The pump was single stage. They just put about a gallon more in it than they needed to finish the run, and if was still idling when it coasted into the shutdown area, some one there shut off the fuel. It sounds like they are way more sophisticated now.

Are you sure the shutoff doesn't just return the pump to the first stage, and shut the throttle? Does it completely dissengage the pump drive? That would be way fancier than what they had when I was helping these guys. I just remember the rules did not allow for any connections in the fuel lines between the tank and the pump. They were worried about them splitting and leaking, especially anywhere near the driver. Not in a wreck, mind you, but just because the cars shake so hard. The lines had to be continuous and uninterrupted from tank to pump.

I've seen what happens when they go lean at full throttle. I think a lot of the failures back then were attributable to this. The modern pumps have all but eliminated the fuel starvation problem and it is actually much less common to see a motor let go now than it was twenty some odd years ago. Of course all of the equipment has changed so much. Way more sophisticated (and expensive) now.

Hell, these guys were running the old Donovan 417 blocks based on the 392 design. They only had two, and maybe enough spare parts to replace the internals once. They were all cast-offs from the bigger teams. If the car broke once, and nothing came out through the sides, we could usually get it back together for another run. If it broke again, the weekend was over. Or if it busted the block. Then it was mix and match parts when we got home to try to put together another running set, usually with more cast-offs bummed from the big kids. The block would be sent out to be welded and remachined. It was amazing how many welds were on those blocks after awhile. This was right at the twilight of the "little guy" in the fuel classes; try running like that now. Just can't be done.

The spark is (or was back then) a key tuning tool. I remember the car ran anywhere from about 35 degrees to something well over 40 degrees. Or something like that; I remember it was a lot. More nitro, more power. More advance, more power. Add more of both when you were really hooked up, and flush with money. If the thing truly dieselled, there would be no control over timing and therefore power or detonation. That, and nitro is just too hard to light anyway. We used to start it on gasoline; I'm pretty sure they still do. The little squeeze bottle in the starter's hand, that he squirts into the injectors, is the only priming it get to start it. It probably still has plain old gasoline in it.

[Mule]

Jeff, they do just bypass the fuel back to the tank. If you listen you will hear them pop & spit a couple of times on shutoff but then they are shut down. Now they mostly use TFX 500 inch blocks and Alan Johnson heads (if they're smart). The squirt bottle is most commonly gasoline. BTW, they can make 70# + of boost.

As for the driving skill required, I was at the US Army tent one day and they had a pretty sophisticated T/F simulator. I made about 30 passes. On 3, the car was still on its wheels. On 1, I was even in my own lane. On none was I still on the gas. On 27, I was upside down & on fire.

[Jeff Higgins]

O.k., so it controls a bypass that is a part of the pump itself? That sounds like a pretty darn simple and obvious solution. Of course with the advantage of purpose-built components available today, I guess there is no reason why they couldn't. I can't even remember what pump they ran way back when, but I'm pretty sure is was rather crudely adapted from something else. Like a farm implement or something...

Those components today are simply amazing. The TFX block is so strong I hear they can actually throw a rod or even break a crank inside of one and still run that block on the next pass. The old cast Donovan and Keith Black blocks would split wide open. The old Lenco two speeds would come apart pretty regularly, as would the Halibrand quick change rear ends. They busted up all of that stuff all of the time. Now you never see a tranny or rear end let go, with over double the power going through them.

Heh heh heh... I ran that simulator too, when they had it up here in Seattle. I never did finish a pass that I actually stayed on the gas. I figured it was rigged just to impress us, but I later heard it is actually quite realistic.

While all the old guys with the funny car are long gone, one guy in our plaster and plastic tooling shop has an old fuel altered. It's the old Nanook. He runs exhibitions with it; all that nostalgia drag stuff that's so big now. I was whining about how hard that Army simulator was to drive when I was out in the shop one day. I didn't see him at the races, but of course he was there. The other guys that were with him said he nailed every pass on the simulator, where the rest of them fared about like us. Gino said is was pretty darn realistic.

[Chocaholic]

It's amazing the driver doesn't pass out from the G's. Great read!

[Chocaholic]

It's amazing the driver doesn't pass out from the G's. Great read!

[Laneco]

I prefer other types of racing to drag racing, but horsepower enamors me... That said, top fuelers are an assault on the senses that simply must be witnessed in person.

A few years back, the top fuelers came to Medford - "Top Fuel Tuesday." Kind of an odd night for a drag race, but the big boys were on their way thru to more important races. The fuelers ran a few 1/8 exhibition runs. That was pretty impressive, but not really that exciting. I was kind of thinking perhaps I'd spent my money unwisely.

Then they lifted the bodywork on the car and did "something". Even though I was only about 20 feet from the rail, I couldn't get a clear visual on what they were doing. But whatever it was, it flat woke up the growl in the bear!

Immediately the exhaust changed pitch and threw out a concussive thumping like a rock concert when you are way way too close to the speakers. You know that feeling? Like a flat hand slapping you on the chest? Only this isn't over amplified music, this is the music that engines make. The lights staged and on green, the world simply exploded with horsepower.

The cars launch so hard and quick they don't even look real. The exhaust sounds slam into your chest like fist, a physical impact that by itself is as shocking as grabbing an electronic ignition. Not the kindly rock concert slap on the chest, but a real blast, a physical PUSH. Then its over. That quick. The air is still whirling around you, your chest is tingling from the sound and it feels like your ears will never ever be right again. The chutes are out, the car is turning off-track. All over and shut-down. Did you blink? If you did, you missed the sight but never could you miss the sheer power of this.

Like I said, not a drag race fan, but I have to say the top-fuelers are unbelievable to watch in real life, up close.

angela

[Mule]

Jeff, people assume that the blocks look like typical race equipment. The new ones do. The older ones look like Frankenstein. The patches have patches. Weld 'm up. Cut 'em square. Fresh sleeves, good as new.

I saw tests once, based on drive shaft deflection that showed over 9000 hp, and that was several years ago.

Angela, the difference was when they stopped squirting gas in to keep it running and turned on the fuel pump. That's the sound of nitromethane.

[Hugh R]

If you've never been to one and think you know about it, well, thats like only having wacked off watching a dirty movie on your TV and thinking you know what actually having sex is like.

[Jeff Higgins]

Originally Posted by Mule

That's the sound of nitromethane.

[Mule]

I love to take newbies into the pits and go up to a Nitro car for a warm up. They get it running, then turn on the pump. Now the good noise starts. They let it idle for a minute. By now the fumes are starting to make your nose burn & eyes water. The newbie is a little concerned. Next they crack the throttle, which sounds more like an explosion than anything related to an automobile (and is probably 130db). The general reaction to this is for the crowd to lurch backwards like a school of fish changing direction on Animal Planet. I tell the newbie, we can go now.

[Laneco]

EXACTLY! You can listen to people talk about it, you can see on on television, but intil you've stood near them when they light off there is ZERO perspective.

Absolute adrenlin rush. I can't even imagine what it would be like in the cockpit...but I wouldn't mind finding out!

angela (hp junkie)

[Jeff Higgins]

I always stand off to the side to avoid the inevitable nitro shower. That stuff just plain burns on your skin, and once your tee shirt is soaked, you just have to take it off. Not such a bad thing depending on who gets soaked...

I just love the guys holding the big plastic garbage bags open behind them. What do they do, hide behind the stands and huff that stuff? Hard-core lunatics. And the guys wheeling the used slicks home - "look what I got at the races, honey!". I used to grab the odd piston and rod or something, but now it seems all the teams want to sell them. Oh well. I've lost all the ones I had anyway.

One of my most cherished memories of the drags is of a day about ten years ago. A couple of my German cousins were in town, so I hauled them out to the Fall Nationals at SIR. Both had seen plenty of racing in Germany, and were going on and on about how loud F1 cars are. They had no idea... I did the obligatory "let's watch 'em warm one up" drill, but I was nice enough to make sure they were off to the side a bit with me. I mentioned they should cover their ears when they saw the guy reach for the throttle, but they knew better. Ah, when he blipped that throttle... it was priceless. You know what happened... Then later, when we were watching the racing (from about the 200 foot mark), I told them to cover their ears when they saw the green light go off and the butterflies flatten. "Oh, they are far enough away now..." They knew better once again. I was nice and gave them some muffs out of my backpack after that. It made an impression... they still talk about that day, ten years later. Great stuff.

[sammyg2]

On my engine we would squirt gasoline into the injector hood to get it started, but when it did it ran only on methanol for about 10 seconds. It was loud, but not crackly. Once all cylinders are fired on methanol we turn on the fuel pump that fed the nitro mix. That was when it got loud.

[rammstein]

It sounds like I need to go watch a race!