It seems to me, this would help the tire shake troubles... (1 Viewer)

[Joker741]

I'm old enough to remember when the nitro cars (both t/f & f/c )
were going 275, 250, 200, and we all loved it!
It's all about The Show!
The smell.
The noise.
The competition.
And... Lots & Lots of Cars participating...
thats what gets folks excited and wanting more!!

Again this is just my 2cents! Larry

I wish I had been alive to see some of the runs from the 50's and 60's. What an awesome time in drag racing that must have been.

People were excited to see the big numbers then. You can't tell me when the top speed someone had run was 215 when you saw a 218 or 220 you weren't in awe or excited that you were there to witness it. Back then, they had never seen a 337 mph pass and never even dreamed the cars could/would go that kind of speed. You can't tell me you don't want to see someone post a 340 mph pass.

I understand everyone is still grieving over Eric, myself included, but slowing the cars down is not the answer. If you want to pack the stands, you will need the big numbers. Just adding my 2 cents to yours. If we keep this up we might have enought to start a fuel team! I am not attacking you in any way, just stating my opinion.

 

[d'kid]

You could see and understand more of what the cars were doing in the late 60-early 70's... and yeah, I miss the weed burner header... heck you can't even smell a car going down the track from the stands now...

But... shakes ain't nothing new... but back in the 'good old days' the talk was the tires were stickin' TOO good and they were 'Tripping' over themselves. kinda like stepping on gum on the sidewalk in flip-flops and stepping right out of them.

The easiest answer, sweep the track and don't put down as much VHT... and shorter, stiffer, sidewalls....

That's my 25cents

 

[n/a]

Just adding my 2 cents to yours. If we keep this up we might have enought to start a fuel team! I am not attacking you in any way, just stating my opinion.

Hey Now Your Talking!!!

Just like the old days... You and I & the guy down the street...
we all pitch in a couple of bucks a month and we go run a fuel car!!
My life long dream,
and I'm not at all taking any of your opinion as hatered.
All ideas are good conversation!!

Larry

 

[downtime]

I like that as well but my guess it would lead to aborted runs that a driver could have driven "through".

We all know from last year how important each round win is in the big picture.

Seems to me that the same type technology that is used for knock sensors could be used... Its all about the calibration of the device. We all know these cars shake violently anyway but sensors can be directional and technology works far more quickly than a human can think or react.

If a computer can calibrate partial throttle responses in an engine, provide ABS braking, and control a mars landing, I see no reason why a product could not be developed to accomplish this type of task.

I know many of us here are racers and not great fans of technology but I believe this might well be worth the research and may also be able to provide important data to a company like Goodyear, for example, in regards to a variety of tire shake scenarios to help develop a safer and better performing product.

 

[none]

Interesting discussion over at the Draglist BB concerning a stiffer (stronger, better?) tire offered to a racer a few years back. No info on who the mfg was, or the background political ramifications, but interesting nonetheless.

Draglist.com Drag Racing :: View topic - TIRE SHAKE KILLS!

While it has now come to light that tire shake, as usually defined, wasn't the actual cause of the Erics' injuries, no doubt the powers that be are now taking a much closer look at tire design & construction, in addition to other safety aspects of these cars. And this is always a good thing.

As an aside, I personally wouldn't mind if the cars performance were limited somewhat. Single mag, smaller pump and blower should do the trick. And let 'em run 95%.

I personally enjoyed fuel racing just as much when the cars were running in the 5-6 second range at 225-250. And there were more of them.

Maybe the nostalgia movement is the true future of this sport.

Sunday, Sunday, Sunday!

32 Top Fuel cars! 32 Fuel Funny cars!

Be There!

JMHO

 

[ozfuel]

Whatever happened to the tire shake testing deal that the Kalitta camp was doing a year or 2 back ? I remember the pics of the wheels with sensors on it.

Mark.

 

[r2]

Whatever happened to the tire shake testing deal that the Kalitta camp was doing a year or 2 back ? I remember the pics of the wheels with sensors on it.

Mark.

If I remember right... That device measured tire growth at speed and or during a run... Tire shake was not its intent... I think...

 

[scotty]

While it has now come to light that tire shake, as usually defined, wasn't the actual cause of the Erics' injuries ...

I think this is the key point about what happened to Eric. It wasn't tire shake as we know it but shake from a tire puncture. A lot of us have experienced the shaking in our car when we've got a totally flat tire and this was similar but way more violent.

"You have approximately an 18-inch movement up and down with the force of about 40,000 or more pounds." ~ Dr. John Melvin from the JFR teleconference

I'll add some more to this picture based on Dr. Melvin's info above and conservative estimates. Again this is ONLY estimates and NOT what truly happened to Eric or what Dr. Melvin has calculated but it does illustrate the violence.

Let's say the tire puncture happened just before half track or about 250 mph (I don't know the true speed). Using an approximation of 115" rollout, the rear tires were turning 2295 rpm. This equals about 38 revs/sec or 38 Hz. The driver is sitting basically on top of the rear-end. Geometrically his head is about the same distance from the pumpkin as the tires are. You can now draw a circle with its center at the coupler/driveshaft that passes through each tire and the driver's head. Because the differential is solidly mounted to the chassis, and the driver is securely strapped to the chassis, they act as an "assembly" rotating about the driveshaft. If the axle is moving up and down, the driver's head is moving side-to-side about the same amount. Dr. Melvin stated that there was about 18" of movement from the partial tire flopping around the axle. That means that the driver's head was moving 18" but lets be conservative and say it was moving 12" side to side.

So imagine someone grabbing you and shaking you side-to-side by 1 foot at 38 times a SECOND. Now add that your head has a helmet on it and is "whipping" even more than your body. That is MAYBE what Eric experienced.

I have seen other damping systems for personnel protection and this problem is VERY difficult mainly because you cannot predict the amplitude (distance moved) or the frequency. Any solution found works best within a "range" but might actually be worse outside of that range. Dr. Melvin states exactly that in the teleconference. I applaud the efforts being put forward by JFR and their consultants. They are much smarter than I but from what little I do know, they are moving in the right direction.

 

[Nitrohaulic]

Exactly, Scott. People are STILL trying to mesh the words "shake" and "vibration." You're not going to prevent what caused Eric Medlen's expiring by curing tire shake. To this day, nobody has ever scientifically even proven what tire shake IS.

I said on another thread already that I've read in truck tire shops that only a few ounces of weight out of balance equals several hundred pounds of force at only 65 MPH.

If you try to place any medium between the driver and the car, I think you have to assume a certain oscillation. When you get another frequency, whatever you put in there is going to give you the opposite of what you intended. I don't believe any thickness of material of any compression rate is going to be correct for every situation.

The darned thing is this. I think Eric got the magic bullet. It may not happen again. It may happen ten times before the year is up. I don't remember anyone ever even being INJURED due to a tire vibrating at high speed, and that jumping to making changes to the construction of the cars based on this one instance may be due more to emotions than in being analytical.

 

[downtime]

Maybe we are thinking about it the wrong way... Maybe we could incorporate a sensor into the headgear so at a certain point shutoff occurs. After all, it is the driver we want to protect and the car (although pricy), is "disposable"...

 

[Nitrohaulic]

Same thing, though. If we're trying to prevent this particular event from happening again and, if it was due to the tire vibrating due to being however much out of balance after being punctured at whatever speed, shutting it off isn't going to stop it.

Maybe this is where titanium wheel studs would have been a good thing? I don't see anything preventing this other than removing the out of balance tire from the car. I've seen several top fuel blowover videos in which a tire and wheel will exit the car without having impacted anything. I'm guessing it's from the engine overrevving, blowing up, locking up, then the tire and wheel sheering the studs from it's own momentum.

 

[The Counterfeiter]

Whatever happened to the tire shake testing deal that the Kalitta camp was doing a year or 2 back ? I remember the pics of the wheels with sensors on it.

This was the SWIFT (Spinning Wheel Intgrated Force Transducer) system, that has been used extensively in Formula 1.
Grubnic ran the car twice with the system. Kalitta and Weld put a lot of money into this and (I believe) offered the results to NHRA and Goodyear with no response.
It was not specifically a tire shake test, it was rather an attempt to gather data about real horsepower and loading on the chassis.
I was at Firebird when the parts arrived for the first test, and still have a brochure from SWIFT. If you would like a copy, let me know - it's very interesting. To my knowledge, this was the only attempt to gather scientific data on the dynamics of a fuel car run. It's too bad that NHRA and Goodyear didn't want to look at the results.