DSLRUsers.com

C&C most welcome guys

I cant think of a better way to ruin a perfectly good set of tyres!.

Nice sharp pics!

Did the ute's bootlid fall open, or do they do this on purpose? I seem to remember the mythbusters demonstrating that the wind drag is lower with the lid up...

Cheers
Steffen.

Steffen wrote:Did the ute's bootlid fall open, or do they do this on purpose? I seem to remember the mythbusters demonstrating that the wind drag is lower with the lid up...

Cheers
Steffen.

He did that on purpose. Later in the day, he had it up again

Well timed shots great tyre distortion,well done

Jeff

Kyle wrote:

Steffen wrote:Did the ute's bootlid fall open, or do they do this on purpose? I seem to remember the mythbusters demonstrating that the wind drag is lower with the lid up...

Cheers
Steffen.

He did that on purpose. Later in the day, he had it up again

I thought the rules stated tonneau cover on or tailgate down for utes??

Love the ute shot by the way, just shows how little pressure is really in the tyres

Honestly, i'm not sure, but here he is, later in the morning... http://www.kylesharpphoto.com/gallery/d ... rag104.jpg

Thanks for the comments guys

Jeff wrote:Well timed shots great tyre distortion,well done

Jeff

OMG, I thought he had a flat! Is this what happens to tyres on take-off? That makes it a very special capture, IMO.

Cheers
Steffen.

Steffen,

If your pressures are too low, then yes, this would be what is expected. Most people normally drive with far too low a tyre pressure, and the manufacturers' recommended presssure for road use is generally focussed towards improving apparant ride comfort, rather than safety, although that is slowly changing. For competition, you need to bump it still further than what might be an optimum pressure for road use.

Kyle, that is a great capture; well done.

Very well done...great shot

Upon the launch tyre pressure is really low so as the rim only sit about couple of cm above the ground, soon after the burnout, temperature increases rapidly and air inside expands, making the tyre filled and pumped up.

If they filled the tyre with 'normal' pressure, it will explode before it reaches maximum speed because of extreme pressure build up inside the tyres.

My understanding is that the low pressure in tyres for the drags allows the tyres diameter to increase during acceleration, thus improving the gearing.

If you look at a top fuel/alcohol car (open wheelers) the effect is more pronounced. The tyres are quite squat and bulge over the rims at rest, but upon acceleration, the tyres become a lot taller, increasing the effective gearing of the differential (or something to that effect).

P

Grip. It is a compromise between grip and drag. The distortion will allow the tyre to grip alot better to the surface of the strip, the burn out serves a couple of purposes, one to lay fresh hot sticky rubber down for added grip and two to warm the tyres up and make them stickier

You'll notice that the tyres do not really grow tall unless they are about to break traction or are a long way down the track. The aim is to maximise the torque and power transferred out via the tyre to push the car along and create as much acceleration as possible.

There is so much more to drag racing than meets the eye. Which is why a photo such as this one really makes people sit up and notice. Which to me is why it is such a great capture!

Brett

I remember, when I was a kid, reading an article about the stats of a Top Fueler (going back about 15 years):

1. The engines generated about 5500 bhp.
2. They accelerated from 0-100km in something like 0.9 sec
3. They reached 300 mph in 400 m (I think now they are getting closer to 350mph)
4. They used up something like 65 litres of fuel which cost about $9/L (back then, I think) per run.
5. Each engine had to be stripped and rebuilt (if it didn't blow up) after each run.
6. They weren't too quick doing a lap around Mt Panorama

P

Reschsmooth wrote:I remember, when I was a kid, reading an article about the stats of a Top Fueler (going back about 15 years):

1. The engines generated about 5500 bhp.
2. They accelerated from 0-100km in something like 0.9 sec
3. They reached 300 mph in 400 m (I think now they are getting closer to 350mph)
4. They used up something like 65 litres of fuel which cost about $9/L (back then, I think) per run.
5. Each engine had to be stripped and rebuilt (if it didn't blow up) after each run.
6. They weren't too quick doing a lap around Mt Panorama

P

Off topic I know. My favourite was that the engine only did about 700 revolutions in total from the start to the finish line...

bwhinnen wrote:

Reschsmooth wrote:I remember, when I was a kid, reading an article about the stats of a Top Fueler (going back about 15 years):

1. The engines generated about 5500 bhp.
2. They accelerated from 0-100km in something like 0.9 sec
3. They reached 300 mph in 400 m (I think now they are getting closer to 350mph)
4. They used up something like 65 litres of fuel which cost about $9/L (back then, I think) per run.
5. Each engine had to be stripped and rebuilt (if it didn't blow up) after each run.
6. They weren't too quick doing a lap around Mt Panorama

P

Off topic I know. My favourite was that the engine only did about 700 revolutions in total from the start to the finish line...

You torque a lot of sense...get it, "torque".....shoot me now!

the tires in both those photos are proper drag tires and really different from your normal car tire. First off drag tires are normally 2 ply side wall, that allows the massive distortion on launch, and its all designed for traction.
Normal street car drag tires don't expand the same way funny car or top fueller tires expand, the expansion in them is simple caused by the sheer width of the tire, the speed of revolution and how simple the tire construction is.
tire pressures are normal, you do adjust them up and down but that is dependant on track and ambient temperatures. basically what you look for is a flat even black line after a burnout, too dark in middle and you drop the pressure, too dark on the outside and you increase it.
Contrary to popular belief the burnout doesn't increase the air temp inside the tire by any significant amount to alter its performance in the short period that the burnout takes place.

kyle, i'd try and get a media pass and get on the edge of track to show the front of car during a launch.

I had a media pass, and I got a bunch of photos from all round the start line

Sadly, I dont have media backing for competition events at wsid... all in good time though

Thanks for ALL the comments guys, much appreciated

the soft wall tyres, with lower tire pressure, are designed to leave a larger "footprint" or "contact patch" on the ground. This maximises grip, minimising slippage. The rotation you see in the tire wall also provides some flex for the drive train, so as to not snap at axle with each launch.

The drag coefficient of the tailgate on a utility is directly proporational to the IQ of the driver, usually.

Nice captures though

As I think already mentioned Kyle, these are great action shots.
Regards Colin

Kyle wrote:I had a media pass, and I got a bunch of photos from all round the start line

Sadly, I dont have media backing for competition events at wsid... all in good time though

Thanks for ALL the comments guys, much appreciated

pfft media accred these with the d70?

michael_ wrote:

Kyle wrote:I had a media pass, and I got a bunch of photos from all round the start line

Sadly, I dont have media backing for competition events at wsid... all in good time though

Thanks for ALL the comments guys, much appreciated

pfft media accred these with the d70?

Yeah right michael