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I"m sorry but I fail to see how a tire exploding makes the guy an idiot.
He's an idiot by the way he did the burn-out, and the parts he had on the car. From the picture, it looks like the tire was a Dunlap 4000 which is speed rated at 118 mph. When you do a one tire burn-out, the differential doubles the tire speed because only one tire is spinning. If you listen, he rev'd out first, then second, and then third, so the speedo was probably showing about 120 mph. That means the spinning tire was going about 240 mph. That's the reason the tire blew up. Also, if you watch the video, you'll see the track person start to go up to the driver to tell him he's doing a 1 wheel burn-out.
Quote:
Originally Posted by Orr89RocZ
how one goes about preventing this by building more than just the motor??
For a burn-out car, you need to have a posi, spool or locker in the rear end to keep both tires spinning and keep the tire speed down.
Also, why have a burn-out car that only spins one tire? You get twice the smoke with two!
IMO, he is an idiot for even entering his car into the contest to begin with. Alot of damage there, Im sure he did not forsee. Maybe its just me, but, I just dont see why anyone would do that with their car?
He sure wowed the crowd though. Im sure he impressed them. well worth the damage, I guess.
It's already been around for awhile... If you look those are Hercules HP 4000's. It doesn't really matter, they're still junk tires. This link might have something to do with the failure too... http://lemon.onecle.com/hercules/hercules-hp4000.html Above all I think the reason the car tore apart is because of all the rust. I've blown more then a few tires in thirdgens and never had anything more then a mess of rubber rubbed all over the fender or some scratches from the belts.
express delivery from the failboat on that one. There is some serious damage to the car there. Frankly its suprising no one was hurt. That was a lot of power unleashed when that tire let go.
I've blown more then a few tires in thirdgens and never had anything more then a mess of rubber rubbed all over the fender or some scratches from the belts.
Have you ever had a belt let go like that? I have seen a couple SUVs get WASTED from a belt letting go doing the speed limit much less spinning like that thing was.
I had a retreaded (wasnt told it was a retread) let go in an old truck at highway speeds. It unwraped and caught the bed side fender support, and caused a lockup. Truck did a 360 in the road. Could have been really bad.
Lots of carnage when a tire come apart at speed. Usually they just blow in the middle.
Have you ever had a belt let go like that? I have seen a couple SUVs get WASTED from a belt letting go doing the speed limit much less spinning like that thing was.
No, of course not.
I wish I had a pic of the one that blew at 80mph on the interstate. All that was left of that one were the beads and some shredded sidewalls. The sidewalls looked like the fringes on Grand Ma's couch.
You know, I'll be the first to call someone a dumbass if they're being a dumbass, but that could have happened to any one of us if you've ever done a burnout. A tire can explode if you have a perfectly working posi and brand new tires on the car... and all the comments about the junk tires and speed rating... heh, speed rating has NOTHING to do with how fast you can spin your tires in a burnout and I know that I'm not going to enter a burnout contest with new tires, I'm going to save junk tires for that. If I enter a burnout contest I'm going to know that something like that can happen, but I'm still not going to be thrilled about it if it does.
Wrong, unless theres a 2:1 ratio difference built into the spider/side gear assembly.
Wheel RPM is engine RPM X trans ratio X final drive ratio. Regardless of how many tires are spinning.
WRONG- Jerrywho is correct.
The differential functions like this: The average speed of both axles equals the average speed of the ring gear. If the ring gear is turning 100 RPM (just for example's sake), and the vehicle is going straight with no tire slippage or spin, each axle is turning at 100 RPM; the average speed of the axles is 100 (left) + 100 (right) = 200; 200/2 = (average axle speed = ring-gear speed) 100. In a turn, with the ring-gear turning 100 RPM, the axle speeds may be some thing like 80 RPM (right) and 120 RPM (left), but the average speed of both axles will still equal ring-gear speed ( 80 + 120 =200, 200/2 = 100). With the ring turning 100 RPM, and one axle's speed is 0 (zero), the average wheel speed still must equal ring-gear speed, so, using the same example ring-gear speed of 100 RPM; ring gear = left + right divided by 2; 100 = 0 (left, stationary wheel) + ? (right, spinning wheel) /2; 100 = (0 + ?)/2; 100 = (0 + 200)/2. Right wheel speed, with left wheel stationary, is twice ring gear speed, which would equate to twice the indicated speed on the speedometer; or, in a car with a 3.00:1 axle ratio, in high (1:1 ratio) gear, at 5000 engine RPM, that right side tire would be spinning at (5000/3) x 2 = 1667 x 2 = 3334 RPM, as opposed to 1667 RPM if the vehicle was going straight with both axles turning at the same speed (RPM).
Bill
P.S.: All of that and $1.50 will get you a cold soda from most any vending machine.
No, a diff splits torque not RPM. If you want to observe this get an OBD-II car with ABS and an open diff.
Go to the ABS menue and select live data, have the cars drive wheels lifted and someone holding one wheel stationary, if what you say is true then the MPH read out of the spinning wheel will will be exactly twice the MPH read out of the speedo sensor.
But you will observe that that is not the case.
Think about it, if what you say is true I could remove the Pass side drive shaft from my Mazda and lock that sides output stationary and instantly take my theoretical top speed from 135 mph to 270 mph. I'm sure the guys at maxton and bonneville would love to know about this new speed secret
No. You could (and would) acheive the equivalent wheel speed on a no-load tire, but you would still have to have the exponentially greater power available to get your Mazda to 270mph. Your example is just like saying my Z28 with a 2:1 axle ratio would hit xxx mph; it wouldn't, without the required power to pull the sky-high gearing (No need for a on this answer).
No, a diff splits torque not RPM. If you want to observe this get an OBD-II car with ABS and an open diff.
Go to the ABS menue and select live data, have the cars drive wheels lifted and someone holding one wheel stationary, if what you say is true then the MPH read out of the spinning wheel will will be exactly twice the MPH read out of the speedo sensor.
But you will observe that that is not the case.
Think about it, if what you say is true I could remove the Pass side drive shaft from my Mazda and lock that sides output stationary and instantly take my theoretical top speed from 135 mph to 270 mph. I'm sure the guys at maxton and bonneville would love to know about this new speed secret
This is what i thought. Around a turn the differential unlocks to allow the outer wheel to spin freely because it has to since it has further to travel. If it didnt it would drag. Power is not being transfered at that point. The moment you punch it around a turn the diff would lock up and transfer torque between both and then both tires would spin equally and cause you to break loose and spin out. The inside tire would be forced to match outer tire speed and when a tire is forced to spin faster than is required, that means you break traction and spin
But locking one tire and spinning the other wouldnt mean its going 2 times as fast. The torque is just transfered to that 1 wheel.
Plus this is just an open differential anyway so it never will lock the other tire transfer power to both tires. It just direct drives 1 axle. I just dont see no load or load changing the overall speed.
EDIT: Looks like they were on a metal plate when doing the burnout. Probably overheated the tire and melted through and just blew up or poor constructed tire. Big rigs blow tires all the time after a enough miles
Do you think the axle side gears and the diff case pinion gears ever disengage from each other? How could they....
And, BOTH axles, via axle side gear, diff case pinion gear, and diff case pinion gear cross-shaft, are equally 'tied' (mechanically, through the afore mentioned gear-train) to the differential case, AND thus to the ring gear....that is why the average speed of the two axles must always equal the speed of the ring gear
Peace, out.
Bill
Last edited by Burnout91; 02-22-2010 at 03:47 PM.
Reason: had to get in the last word in
the bead belt failed..= tire side wall at rim seat. broke
this should never take place ever! tire failed.. bottom line.
nothing to do with tire speed. as this steel (belt)cable. should never brake.
tire let go way before it's time. plane and simple.
and did you see how it split the seam of the car..
Do you think the axle side gears and the diff case pinion gears ever disengage from each other? How could they....
And, BOTH axles, via axle side gear, diff case pinion gear, and diff case pinion gear cross-shaft, are equally 'tied' (mechanically, through the afore mentioned gear-train) to the differential case, AND thus to the ring gear....that is why the average speed of the two axles must always equal the speed of the ring gear
Peace, out.
Bill
The axles dont physically disengage but maybe I have the wrong understanding of the differential. I'm looking at my zexel torsen diffs and the worm gears will lock and spin with the axle, forcing both axles to rotate together when its in posi mode. If you stop one wheel, the other wheel will still rotate the same speed as before but the worm gears disengage to rotate independently around the axle thats not moving. I dont see anything inside the posi that would do increase gear ratio across the axle and cause the one tire to spin faster than it would when both tires were spinning. Transfer of torque there not rpm.
But in this case, i think that guy just had an open diff rear end. So it doesnt matter if one wheel was locked or not. Open diffs mean just one wheel is tied to the drive train. The other axle just free floats there to spin at whatever speed the car is moving at. Doing a burnout loads the tires/motor/drivetrain. Maybe not as much as a full traction WOT pull, but does load it. So being an open diff, the speedo will show same speed as the tire because the speedo is calibrated based on tire diameter and gear ratio. Whatever the tire spins at the speedo shows. Why would there be an amplification factor across the spider gears on either differential design?
I would think tire failure based on above mentioned. I've seen TONS of 1 wheel peelers and many do burnouts but never seen a tire explode unless it wore past the rubber and air pressure blow it open.
The reason he's an idiot and anyone who does this is because it's a waste of money and does not prove you have anything. I have never understood the burnout contests because they are useless. You do a burnout at the dragstrip because you need the tire heated up to stick that is needed. But this is just dumb plain and simple.
I agree, This guy is a total idiot and by the looks of it he was proud of it to by the way he was raising his fist into the air. It gets me to see how people get enjoyment out of burnout contests. Hell any car can do a burnout what is so special about that. So me some hard work high horsepower and low ETs and to me thats is enjoyment................
I saw that vid just the other day but from a different camera angle. I have a question on the one wheel peel, I have the 'limited slip differential'- so that means it isn't a true posi, but it still won't one wheel peel, right? And I heard when he shifted gears, when I've done a burn-out, in my car (auto trans) it almost always shifts into second and once third (its a TH-350)
I don't know how to quote, but someone above has a video of their camaro having some fun on 7 cylinders...
Well I have one of me in my trans am doing a burnout on 6 cylinders! (its a 350, no kidding). Two lobes on the cam were completely worn down, there was a collapsed lifter, and it had a couple bent pushrods! I didn't know that at the time, I mean I knew there were some problems but I didn't know it was that bad! You can beat these engines into the ground and they still run like champs. And they're relatively cheap to fix too. There isn't much smoke in the vid because the tires were so shot, and I bet the poor car was making half the power it is now. And sorry for the angle, you get more of my hair than of the car lol, but it was filmed on my phone. I gotta bring my brother along next time to film.
after i did the burnout and donuts i did a tune up and when i pulled 2 plugs out oil poured out......oops.......lol the car ran for a while until i pulled the 305 and in the middle of doing a well built 355. im also building the transmission and rear end to handle the power.
The differential functions like this: The average speed of both axles equals the average speed of the ring gear. If the ring gear is turning 100 RPM (just for example's sake), and the vehicle is going straight with no tire slippage or spin, each axle is turning at 100 RPM; the average speed of the axles is 100 (left) + 100 (right) = 200; 200/2 = (average axle speed = ring-gear speed) 100. In a turn, with the ring-gear turning 100 RPM, the axle speeds may be some thing like 80 RPM (right) and 120 RPM (left), but the average speed of both axles will still equal ring-gear speed ( 80 + 120 =200, 200/2 = 100). With the ring turning 100 RPM, and one axle's speed is 0 (zero), the average wheel speed still must equal ring-gear speed, so, using the same example ring-gear speed of 100 RPM; ring gear = left + right divided by 2; 100 = 0 (left, stationary wheel) + ? (right, spinning wheel) /2; 100 = (0 + ?)/2; 100 = (0 + 200)/2. Right wheel speed, with left wheel stationary, is twice ring gear speed, which would equate to twice the indicated speed on the speedometer; or, in a car with a 3.00:1 axle ratio, in high (1:1 ratio) gear, at 5000 engine RPM, that right side tire would be spinning at (5000/3) x 2 = 1667 x 2 = 3334 RPM, as opposed to 1667 RPM if the vehicle was going straight with both axles turning at the same speed (RPM).
Bill
P.S.: All of that and $1.50 will get you a cold soda from most any vending machine.
Srry but none of that makes sence. The only way axle speed will be diffrent form the ring gear speed is if the both tires are off the ground. One will spin backwards and one will spin forwards making them both travel half the speed of the ring gear not doubling it.
Even if all you say was true we really dont know if he has an open diff or not. Could be just a worn out clutch posi. No other gears at all in that diff besids the ring and pinion.
Ok whats your point. The only diffrence between going straight with both axles and having one stoped is the idler gears will turn to compinsate for the one axle standing still and the other one turning.
For example i did this the other day on my s10. Wanted to check the gear ratio in my rearend. So i jacked one tire off the ground and left the other one down. The code in my glove box said it came with 3.73s. Turned the wheel one full turn and guess what the pinion yoke turned abour 3 3/4 turns. So ur telling me i acturaly have 1.865 gears in my rearend cause the axle off the ground was turning twice as fast as the carrier. Didn't know chevy ever used that gear in anything.
Yeah, thats what I was thinking. The idler / spider gears in the differential will turn to allow the other axle to move when one is stopped. They just rotate around each other. As long as they are all the same size, no gear reductions, they should turn the same. Picture on howstuffworks clearly shows that.
Heres a better one, look at the 1 minute mark. One side is stopped, one moves. Same as the ring gear speed, atleast it looks that way to me. Maybe it is moving slightly faster but it looks like the free floating spiders are not the same size? http://www.youtube.com/watch?v=FKaF20iFU9s
Notice the change in speed of the tire when the other is stopped. I'm done trying to explain it though. That is just how it is.[/quote]
Ofcourse the still spinning wheel spins faster when the other stops, the remaining wheel cant provide as much resistance a both, but while the wheel spins faster the engine RPM goes up as well because of the drop in load.
I gave you a test to try but since not everyone here has a good scanner and a vehicle capable of live data streaming heres a simpler test anyone here can do even with a posi.
1320 guy did this but to confirm your "theory" you'll need to do it twice. Once with both wheels off the ground with another person turning the opposite wheel in the same direction and speed as you turn yours.
Say you had a 3.5:1 rear, turning the wheels once would equal 3.5 turns of the drive shaft, now if you folks are right (and you are not ) then with that friend holding his side still is will take you 7 turns of the wheel to equal 1 turn of the drive shaft.
Regardless of your actual ratio it would be simple enough to observe that it takes exactly double the input RPM to equal the same output RPM.
Do this test, then check in and admit that you actualy learned something
Ofcourse the still spinning wheel spins faster when the other stops, the remaining wheel cant provide as much resistance a both, but while the wheel spins faster the engine RPM goes up as well because of the drop in load.
The differential functions like this: The average speed of both axles equals the average speed of the ring gear. If the ring gear is turning 100 RPM (just for example's sake), and the vehicle is going straight with no tire slippage or spin, each axle is turning at 100 RPM; the average speed of the axles is 100 (left) + 100 (right) = 200; 200/2 = (average axle speed = ring-gear speed) 100. In a turn, with the ring-gear turning 100 RPM, the axle speeds may be some thing like 80 RPM (right) and 120 RPM (left), but the average speed of both axles will still equal ring-gear speed ( 80 + 120 =200, 200/2 = 100). With the ring turning 100 RPM, and one axle's speed is 0 (zero), the average wheel speed still must equal ring-gear speed, so, using the same example ring-gear speed of 100 RPM; ring gear = left + right divided by 2; 100 = 0 (left, stationary wheel) + ? (right, spinning wheel) /2; 100 = (0 + ?)/2; 100 = (0 + 200)/2. Right wheel speed, with left wheel stationary, is twice ring gear speed, which would equate to twice the indicated speed on the speedometer; or, in a car with a 3.00:1 axle ratio, in high (1:1 ratio) gear, at 5000 engine RPM, that right side tire would be spinning at (5000/3) x 2 = 1667 x 2 = 3334 RPM, as opposed to 1667 RPM if the vehicle was going straight with both axles turning at the same speed (RPM).
Bill
P.S.: All of that and $1.50 will get you a cold soda from most any vending machine.
You drunk?
So you're saying if I permanently stopped one of my wheels from being able to spin and then put that wheel on a slippery surface, let's say ice, that I could just drag that wheel and drive down the road twice as fast with the same rpm ? That's basically what you are saying.
You're right, that is what I am saying; your speed would be limited by the amount of power available to pull the gearing. But, don't drag the wheel. Remove the wheel / tire assembly. Tack weld the axle flange to the axle housing, then weld a caster onto the axle flange so that it supports the car and rolls freely. Have a friend, or an enemy, or even ls six, ride along side you to get a true speed reading and then compare it to the reading on your speedometer. Be sure to get some video so that you can rub my nose in it. Report back to us. Or don't...
Last edited by Burnout91; 02-25-2010 at 04:29 PM.
Reason: went to get ****-faced drunk.
I don't get why this is that hard... even the example of it being up in the air works out, you're not turning the pinion gear, turn one side and the opposite side turns at the other speed backwards, the ring gear in housing isn't moving and the average of the 2 tires is 0.
It still works if you have a posi, posis still have spider gears, they just have something (usually clutches or cones) that add friction to the assembly if the 2 sides try to turn at different rates. Even with a good posi, if one tire has significantly more traction than the other you will sometimes do a one wheel burnout. Take an extreme example of this, say one wheel is bolted down, or the posi is worn, the motion that would normally be delivered to the un moving wheel now gets delivered to the opposite side by the spider gears driving that side at 2x that of the ring gear.
Srry but none of that makes sence. The only way axle speed will be diffrent form the ring gear speed is if the both tires are off the ground. One will spin backwards and one will spin forwards making them both travel half the speed of the ring gear not doubling it.
Even if all you say was true we really dont know if he has an open diff or not. Could be just a worn out clutch posi. No other gears at all in that diff besids the ring and pinion.
Really? No axle-shaft side gears? No diff case pinion gears?
Oh, it must be a Detroit Locker then, right? But wait, you said clutches....
14psi, pump gas street tune 
? That's basically what you are saying. 
