The difference between 850 horsepower and 10,000 horsepower

By now most of us have read (several times) the classic list of top fuel dragster facts, which are ridiculous but generally true. One of them reads thus:

Lets say the you are driving the average $140,000 Lingenfelter twin-turbo powered Corvette Z06. Over a mile up the road, a Top Fuel dragster is staged & ready to launch down a quarter-mile strip as you pass by it. You have the advantage of a flying start. You run the ‘Vette hard up through the gears and blast across the starting line & pass the dragster at an honest 200 MPH. Just as you pass the Top Fuel Dragster the ‘tree’ goes green for both of you. The dragster launches & starts after you. You keep your foot down hard, but you hear an incredibly brutal whine that sears your eardrums & within 3 seconds the dragster catches & passes you. He beats you to the finish line, a quarter-mile away from where you just passed him. Think about it – from a standing start, the dragster had spotted you 200 MPH & not only caught, but nearly blasted you off the road when he passed you within a mere 1320 foot long race!

It's hard to find a drag strip with a run-up that will allow a Corvette to hit 200 MPH by the time it arrives at the starting line, but here's the next best thing:

Summary: an 850-horsepower hot-rod truck takes off from the starting line on a drag strip. Six seconds later, a top-fuel dragster takes off in pursuit and passes it in fairly short order. Based on the 1/4-mile times of the se vehicles you know who's going to win without seeing the race, but it's still remarkable to see the difference in speed in real life.

Along the way, I found

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Along the way, I found

Seems to me you'd damage your ears even with good hearing protection.

A friend won tickets for a major event in Las Vegas a couple of years ago, and I was stunned to see the numbers of people without hearing protection, not even for their young kids.

Reading that made me reflect that I hadn't been to an event in years. So, with a little research I found that the NHRA Arizona Nationals is in February and bought tickets !!

Yeah, the sound of a top fuel dragster is b_r_u_t_a_l . Last time I took hard cover shooters ear muffs . Saves the hearing but your whole body actually vibrates with the low frequency sound waves as they pass you. All American V8 power to the max ... don't get no better !!

A friend won tickets for a major event in Las Vegas a couple of years ago, and I was stunned to see the numbers of people without hearing protection, not even for their young kids.

I wonder what kind of hearing protection would be adequate. A quick Google search claims 150 to 165 decibels for a top fuel dragster; it's not clear whether that's down on the track or up in the stands, but even if it's down at the track, I can't imagine it's much quieter in the stands. Howard Leight Max earplugs have an NRR of 33, which would only get you down to 120 decibels, still enough to wreck your ears. Seems to me you'd need to gear up like a carrier flight deck crew members, with complete cranial coverage, in order to prevent massive hearing damage. Yikes.

What?

From personal experience, I've used these in the stands even though they're only rated at NNR 30. It works for me because my preferred seating is at the end of the strip and the peak sound is therefore quite transient. There is the added benefit that you can easily take them off between runs. However if your on the line ... muffs _and_ in ear plugs would be prudent. Your body is still going to take a pounding even if your ears are protected.

I have been to many Drag race venues where Top Fuel cars run. There is a big difference in sound pressure depending on where you are. Starting line, close to the fence, is extreme! I wear the foam earplugs and then hold my hands over my ears as the cars launch and go by. I have taken pictures where I just had earplugs only. Yes, 120+ decibels is loud but duration of the sound is a big factor as well. It is a short burst.

More amazing facts about Top Fuel engines here: Inside 10,000 Horsepower

Amazing article. I didn't know the supercharger was bungied in place, but it makes a great deal of sense.

Not "bungied in place" as much as restrained with "bungies" should it break the fasteners that hold it in place. I think I read where those fasteners are made to self destruct upon an intake explosion. It is in the rules book that the superchargers must be restrained upon catastrophic failure. They must also run what is called a diaper on the lower engine block area to catch parts and oil coming out of the engine when they blow up!

Summary: an 850-horsepower hot-rod truck takes off from the starting line on a drag strip. Six seconds later, a top-fuel dragster takes off in pursuit and passes it in fairly short order.

To be fair, that's an off-road race truck, which is likely geared for the desert. What's the top end on those? Maybe 125? Maybe less? Whatever it is, the funny car looked like passed it like it was standing still.

Ok, I had to do the math on this one. At 150mph you are moving at 220 fps, it will take you 4.5 seconds to travel 1000 feet. Current top fuel times for the 1000 foot strip are about 3.7 seconds at 330 mph. No only will the dragster pass you it will be going more than twice your speed. WOW! As for the noise it is short duration so wearing plugs and muffs in the stands you should be ok; not wearing anything will likely leave you with permanent hearing loss.

More amazing facts about Top Fuel engines here: Inside 10,000 Horsepower

Thanks for the link, that was really interesting, especially Part 2. I knew there was a clutch that gradually engaged over most of the length of the run, but I always assumed it was a simple centrifugal mechanism; I was surprised to learn that there are 12 steps of progressive engagement, with the timing of each one selected by the crew and controlled by the on-board computer. More sophisticated than I imagined.