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[ANSWERED] fishtail to the RIGHT

 
Old 04-19-2019, 02:44 PM
  #41  
sstonebreaker
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And yet, despite all of that pontificating, the vette still fishtails on a flat surface. Not a crowned road. A parking lot. I guess his torque tube is busted.

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Old 04-19-2019, 05:53 PM
  #42  
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ZMMMMM asked a great question...one for the ages and Tadge’s response was both enlightening and educational. One of the best “Ask Tadge” to date
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Old 04-19-2019, 06:35 PM
  #43  
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top fuel dragsters have the back wheels close together so they don't fishtail on burnouts or at top speed. . try doing a burn out on the other side of the road where the low side of the road would be on the left of the car and see what happens
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Old 04-19-2019, 11:13 PM
  #44  
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Originally Posted by sstonebreaker View Post
And yet, despite all of that pontificating, the vette still fishtails on a flat surface. Not a crowned road. A parking lot. I guess his torque tube is busted.

https://www.youtube.com/watch?v=krM6n1-ZwgA
Now wait a second. On the first burn out, rear of car went right...."like all Corevettes do" (apparently). Right? Then when that tool turned around and came back...rear of the car went LEFT. Wait...WUT?

In both instances, car's rear went very slightly to the camera person's right. I'd say the parking lot sloped slightly to the right. Broken tq tube or not.
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Old 04-19-2019, 11:31 PM
  #45  
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I said road slope matters.

I said vehicle barrel roll torque does not.

You finally agree with me Tom and Stone.. im just going to see how long it takes you to realize it. Few more hours perhaps. Slowly but surely.

The fact that the car fish tailed one way going one direction, and the other way the other direction, shows that Stone's theory that the cars torque weights and favors 1 wheel, is not true.... not when a torque tube is solid and doing its job properly.

Torque tube is not busted Stone, it did its job very well.

...Few more hours perhaps? Maybe days? Sooner or later though, Slowly but surely.

Last edited by Mikec7z; 04-19-2019 at 11:35 PM.
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Old 04-20-2019, 12:00 AM
  #46  
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Originally Posted by Maxie2U View Post
One of the best “Ask Tadge” to date
That's pretty sad, that this is the "tech" people want to glean from Tadge. Then they argue about what the guy told us.
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Old 04-20-2019, 12:02 AM
  #47  
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Originally Posted by Mikec7z View Post
You finally agree with me Tom and Stone.. im just going to see how long it takes you to realize it. Few more hours perhaps. Slowly but surely.
Say what? I never disagreed with you. And I've realized that all along.
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Old 04-20-2019, 12:07 AM
  #48  
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the "broken torque tube or not... and eye roll"... made me think we are on different pages.

I will state that IF the torque tube was broken, then there would be frame twist in the barrel roll direction, and that WOULD affect one tire breaking loose first each time, and that WOULD cause the car to fishtail to one side most of the time (unless the slope it was on was pretty severe to one side or the other.)

Last edited by Mikec7z; 04-20-2019 at 12:08 AM.
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Old 04-20-2019, 12:14 AM
  #49  
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Originally Posted by Mikec7z View Post
the "broken torque tube or not... and eye roll"... made me think we are on different pages.
I got you. No, I was poking fun at stone for the "broken tq tube" comment b/c of course we all know it wasn't broken.



Originally Posted by Mikec7z View Post
I will state that IF the torque tube was broken, then there would be frame twist in the barrel roll direction, and that WOULD affect one tire breaking loose first each time, and that WOULD cause the car to fishtail to one side most of the time (unless the slope it was on was pretty severe to one side or the other.)
Nope. The frame is way, WAY more than capable of resolving the tq between the engine assy and the diff. The frame would not flex in a meaningful way. Not sure if the diff ears/frame mounts on the C5^ could handle that load since it wasn't designed to though.
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Old 04-20-2019, 12:18 AM
  #50  
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it actually would flex, and that slight bit of momentum/inertia will always put weight on one side of the rear axle and on one rear tire beyond the other... if there is no torque tube to keep it all very rigid.
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Old 04-20-2019, 12:49 AM
  #51  
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I guess. I mean, even granite flexes, so yeah, it'll flex. A meaningful amount? No. Just like even though an aluminum (of steel) tq tube can flex ('cause everything flexes some)...it ain't a meaningful amount as it relates to this conversation.

The C4's frame is designed such that it's stiffness is ~2770 ft-lb/degree in torsion. Well...the baddest assed engine ever put in a C4 made 375 lb-ft*2.66 first gear ratio...so that car is sending 997.5 lb-ft down the drive shaft, into the diff and into the motor and diff mounts in reaction tq. So maybe it's twist the frame 1/3 of one degree? Not sure how much "momentum" you're going to build in the twisting direction with that degree of amplitude. Not much. I'd bet money that you get more twist, slop and variances in all your rubber bushings -drivetrain mount and suspension mounts.

The frame doesn't flex in torsion, a meaningful amount.
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Old 04-20-2019, 12:57 AM
  #52  
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its not the flexing 2 inches that matters, its when the frame catches and rebounds a bit.

So lets say the drives side goes down and passenger front frame goes upward (im too tired to think which way it should or shouldnt go right now, so just roll with me here for a sec)

Lets say car could pop a wheelie... and does...

passenger side starts going up and drivers side down... it only goes so far before frame stops it... so as the frame stops it, the front has momentum in the counter clockwise direction. For the rear of the car to stop this, it has to have force in the clockwise direction...

and this puts a lot of extra weight for a moment on the drivers rear wheel, and lightens the load on the passenger rear wheel, and thats that... passenger side unhooks, and its over.

Happens like clockwork every time (but i cant remember what side right now because im tired and getting old)

Last edited by Mikec7z; 04-20-2019 at 12:57 AM.
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Old 04-20-2019, 01:15 AM
  #53  
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Originally Posted by Mikec7z View Post
its not the flexing 2 inches that matters, its when the frame catches and rebounds a bit.
2 inches?? Who said anything about 2 inches? Not me. I said, 1/3 of 1 degree. That is such a small amount, you couldn't see it happen. I highly doubt that there is much "rebound" from that....just as the "rebound" in flex of the tq tube is meaninglessly small.



Originally Posted by Mikec7z View Post
Happens like clockwork every time
Yeah? Here is a guy on the C4 forums that has an '84, IRS intact. I don't see the frame bouncing/rebounding/momentum....It just launches straight and level. Like ANY IRS car should.

C4 Launch/fast pass on IRS

Also note that his rear didn't (ahem) slide to the right.


.

Last edited by Tom400CFI; 04-20-2019 at 01:16 AM.
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Old 04-20-2019, 01:35 AM
  #54  
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i believe torque tube prevents it, and ill leave it at that. 2 c4 photos above launching wheelies easily demonstrate AT LEAST 2 inches of rotation to the front of the car. And yes, that is well over 1 degree.
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Old 04-20-2019, 01:40 AM
  #55  
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Right. Those two pics were of C4's with a solid rear axle conversion and are not relevant to this conversation. Any IRS prevents it b/c the tq is resolved through the frame, which is way stiffer than stiff enough....and I'll leave it at that.
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Old 04-20-2019, 07:37 AM
  #56  
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Originally Posted by Bowtie52 View Post
Road Crown is a coverall excuse......the car can and does break loose causing the rear end to swing to the right.....yes it can and does this on wet pavement, dry pavement and it even happens if acceleration occurs as the tires make contact with road pavement striping. Outside ambient temps above 60 with full sun on the streets/road and the car will break free......something that might be worth looking into is the rubber compound used by Michelin as my tires are the original ones that came on the car with just over 17500 and it is a 2017 Z06 3LZ M7.

I'm not a rocket scientist, brain surgeon, or race car driver I'm just an average guy who does not track the car but the breaking loose of the rear does happen pure and simple maybe not on all Z06's but it does happen.
It happened to me when I kicked down at 70mph ZR1 ( a little scary )
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Old 04-20-2019, 04:12 PM
  #57  
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And yet the car fishtails. You guys are grasping at straws.


Last edited by sstonebreaker; 04-20-2019 at 04:33 PM.
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Old 04-20-2019, 05:14 PM
  #58  
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Found a Meme you like? You going to use it in ALL your threads now?

Originally Posted by sstonebreaker View Post
And yet the car fishtails. You guys are grasping at straws.
Are we? Here is what Tadge (the chief engineer for the car) said.

Originally Posted by Tadge
I think you guessed the major factor in your question: Road crown. Although barely noticeable on many roads, virtually all have some degree of crown.


Likewise although barely noticeable in many parking lots, virtually all have some degree of slope...for drainage. The car in the vid went to the opposite directions in both burnouts. What's more likely: the parking lot was sloped to the camera man's right? Or the engine was running in reverse rotation for the second burn out?

Talk about grasping at straws.



.

Last edited by Tom400CFI; 04-20-2019 at 05:16 PM.
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Old 04-20-2019, 05:59 PM
  #59  
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Originally Posted by sstonebreaker View Post
And yet the car fishtails. You guys are grasping at straws.

Of course it is going to fishtail, but how much relative to another format or moment in time? One tire is always going to break loose before the other. Top fuel dragsters may slightly fish tail during their burn outs, and they are designed not to at all.

We dont know what the driver was doing or how flat the surface the driver was on.... does not mean torque tubes still dont make your original posts null and void about frame twist. Torque tubes do, your first post was irrelevant to our cars c5-c7
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Old 04-30-2019, 08:05 AM
  #60  
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Forward to 1:30.

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