[Z06] Wheel Hop
#1
Pro
Thread Starter
Wheel Hop
Ok, sorry newbie here again, I tried to do a burnout and car is hooking like crazy, with traction control off. I have the Hankook Ventus and they seem to be pretty sticky. Second time I tried I got wheelhop this was trying to launch the car at 2000rpm.
On my 2006 m6 gto in at 2000 rpms it will burnout through second gear and give a nice side kickout in 3rd gear.
I realize this car has the trans in the back, is this what is causing the super gecko like grip.
Oh yeah, I got forgelines, 18 275 35 front, 19 305 30s out back.
Thanks,
Jabba
On my 2006 m6 gto in at 2000 rpms it will burnout through second gear and give a nice side kickout in 3rd gear.
I realize this car has the trans in the back, is this what is causing the super gecko like grip.
Oh yeah, I got forgelines, 18 275 35 front, 19 305 30s out back.
Thanks,
Jabba
Last edited by BLKWDWZ06; 04-11-2011 at 07:04 PM.
#2
Burning Brakes
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First off, why would you try to do a burn out with the traction control on?
your GTO had 245's in the rear?
These cars will hop. Mine was real bad when I first got it. The tires were pretty crappy though. I replaced (after doing some custom work so they would fit) the old tires with 335/30's and I rarely have wheel hop anymore. Not sure what is the best fix for wheel hop. All I know is that it breaks stuff.
your GTO had 245's in the rear?
These cars will hop. Mine was real bad when I first got it. The tires were pretty crappy though. I replaced (after doing some custom work so they would fit) the old tires with 335/30's and I rarely have wheel hop anymore. Not sure what is the best fix for wheel hop. All I know is that it breaks stuff.
#3
Pro
Thread Starter
First off, why would you try to do a burn out with the traction control on?
your GTO had 245's in the rear?
These cars will hop. Mine was real bad when I first got it. The tires were pretty crappy though. I replaced (after doing some custom work so they would fit) the old tires with 335/30's and I rarely have wheel hop anymore. Not sure what is the best fix for wheel hop. All I know is that it breaks stuff.
your GTO had 245's in the rear?
These cars will hop. Mine was real bad when I first got it. The tires were pretty crappy though. I replaced (after doing some custom work so they would fit) the old tires with 335/30's and I rarely have wheel hop anymore. Not sure what is the best fix for wheel hop. All I know is that it breaks stuff.
did you tub out to get 335 on, my car is got hairs to spare before i start grind the rims and tires
#5
Burning Brakes
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#6
Melting Slicks
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Welcome to C5 - C6 Corvettes.
What you think is wheel hop is the entire driveline boucing up and down. Go to the Pfadt Racing web site and take a look at the videos they took of the powertrain movement.
It you continue to allow the powertrain to bounce up and down the problem will eliminate itself by breaking the trans - diff housings where they bolt together. Big $$$$$
Get the Trans - Diff brace and Pfadt's rear diff mount.
What you think is wheel hop is the entire driveline boucing up and down. Go to the Pfadt Racing web site and take a look at the videos they took of the powertrain movement.
It you continue to allow the powertrain to bounce up and down the problem will eliminate itself by breaking the trans - diff housings where they bolt together. Big $$$$$
Get the Trans - Diff brace and Pfadt's rear diff mount.
#10
Melting Slicks
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#13
Melting Slicks
I'm not convinced anyone knows wtf is going on with it. I hear a lot of speculation and people thinking they did this and that which fixed it...but we are all just average Joe's making wild guesses.
#14
Pro
Thread Starter
#15
Team Owner
While I don't quite condone going to these measures, here's another theory on wheel hop that has been circulated around....
Correct fix is a larger left rear half shaft and not the shocks or the tires on their own as the cause of power hop
During ZR1 development, Corvette engineers were dismayed to find that zero-to-60 performance was less than anticipated. Major increases in power, torque and traction over the Z06 were not delivering the expected reduction in acceleration times.
“The problem,” reveals Corvette engineering development manager Dave Wickman, “was power hop.” During launch, the ZR1’s rear tires were sticking and releasing in an unfavorable manner, which excited the entire drive-line into a torsional resonance.
All mechanical systems resonate at some natural frequency.
Think of a plucked harp string, a ringing church bell or the rim of a martini glass stroked by a damp finger.
From the crankshaft to the rear tire patches, the ZR1’s driveline constitutes a mechanical system with a particular natural frequency.
When excited by the staccato torque/no-torque conditions that follow an abrupt first-gear clutch engagement, developmental ZR1 mules were resonating — hopping — at the driveline’s natural frequency.
The traction characteristics of the new Michelin Pilot Sport 2 radials, combined with the torque characteristics of the new LS9 supercharged V8, the suspension dynamics provided by ZR1’s softer spring rates and the damping properties of the electronically controlled magneto-rheological (MR) shock absorbers, had driven the new Corvette prodigy into an uncharted corner of the performance map. Something had to be done.
Wickman’s development team went to work.
“Substantially increasing the driveline’s stiffness would shift its natural frequency away from the resonance point,” notes Wickman.
“Unfortunately, greater stiffness usually means added mass, something we strive to avoid.
“The smarter solution was decoupling the left and right sides of the driveline by using half-shafts with significantly different natural frequencies.
In production, the ZR1’s left half-shaft is a 40mm (1.57-inch) solid steel rod while the right one is 33mm (1.30-inch) in diameter, yielding a 1.5 times difference in stiffness and, therefore, natural frequency.”
Programming the MR dampers was the second half of the solution.
Corvette ride and handling engineer
Jim Mero explains:
“With the car at rest, the dampers provide essentially no damping. So we created a lift-dive algorithm (software) that would automatically configure the suspension for optimum launch traction.”
Following experimentation, the optimum arrangement turned out to be the full 100 percent of available rebound damping in front and 30 percent of maximum jounce damping at the rear.
So, when the ZR1 settles back on its haunches following an abrupt clutch engagement, the rearward pitch motion and resulting damping forces supplement the rear tires’ static load. That maximizes tire-to-road adhesion.
The icing on the cake is ZR1’s traction control system.
Mike Petrucci, responsible for chassis controls development, explains: “The section of the traction control logic applicable to launching the ZR1 aggressively from rest is programmed to allow a fruitful amount of rear-wheel slip as long as the steering is pointed dead-straight ahead.
This allows owners to experience entertaining street performance. By keeping the traction control actively engaged, they should be able to come very close to the 3.4-second zero-to-60 acceleration figures we’ve measured in ZR1s under ideal circumstances.”
Correct fix is a larger left rear half shaft and not the shocks or the tires on their own as the cause of power hop
During ZR1 development, Corvette engineers were dismayed to find that zero-to-60 performance was less than anticipated. Major increases in power, torque and traction over the Z06 were not delivering the expected reduction in acceleration times.
“The problem,” reveals Corvette engineering development manager Dave Wickman, “was power hop.” During launch, the ZR1’s rear tires were sticking and releasing in an unfavorable manner, which excited the entire drive-line into a torsional resonance.
All mechanical systems resonate at some natural frequency.
Think of a plucked harp string, a ringing church bell or the rim of a martini glass stroked by a damp finger.
From the crankshaft to the rear tire patches, the ZR1’s driveline constitutes a mechanical system with a particular natural frequency.
When excited by the staccato torque/no-torque conditions that follow an abrupt first-gear clutch engagement, developmental ZR1 mules were resonating — hopping — at the driveline’s natural frequency.
The traction characteristics of the new Michelin Pilot Sport 2 radials, combined with the torque characteristics of the new LS9 supercharged V8, the suspension dynamics provided by ZR1’s softer spring rates and the damping properties of the electronically controlled magneto-rheological (MR) shock absorbers, had driven the new Corvette prodigy into an uncharted corner of the performance map. Something had to be done.
Wickman’s development team went to work.
“Substantially increasing the driveline’s stiffness would shift its natural frequency away from the resonance point,” notes Wickman.
“Unfortunately, greater stiffness usually means added mass, something we strive to avoid.
“The smarter solution was decoupling the left and right sides of the driveline by using half-shafts with significantly different natural frequencies.
In production, the ZR1’s left half-shaft is a 40mm (1.57-inch) solid steel rod while the right one is 33mm (1.30-inch) in diameter, yielding a 1.5 times difference in stiffness and, therefore, natural frequency.”
Programming the MR dampers was the second half of the solution.
Corvette ride and handling engineer
Jim Mero explains:
“With the car at rest, the dampers provide essentially no damping. So we created a lift-dive algorithm (software) that would automatically configure the suspension for optimum launch traction.”
Following experimentation, the optimum arrangement turned out to be the full 100 percent of available rebound damping in front and 30 percent of maximum jounce damping at the rear.
So, when the ZR1 settles back on its haunches following an abrupt clutch engagement, the rearward pitch motion and resulting damping forces supplement the rear tires’ static load. That maximizes tire-to-road adhesion.
The icing on the cake is ZR1’s traction control system.
Mike Petrucci, responsible for chassis controls development, explains: “The section of the traction control logic applicable to launching the ZR1 aggressively from rest is programmed to allow a fruitful amount of rear-wheel slip as long as the steering is pointed dead-straight ahead.
This allows owners to experience entertaining street performance. By keeping the traction control actively engaged, they should be able to come very close to the 3.4-second zero-to-60 acceleration figures we’ve measured in ZR1s under ideal circumstances.”
#18
I notice my c5 z06 tends to get a little wheel hop or driveline hop (who knows which one) when traction is reduced, like on wet roads or when the tires are cold, or today while reversing up a grassy slope, very low traction situation and it started hopping a little before I let off.
I have some wheel spin when the tires were warm on dry pavement and oddly enough there was no bounce then.
About twice, Under hard acceleration I do think I experienced some 'power hop' where i felt a bounce when the tires were right at their limits of grip during 1st - 2nd gear pulls. But it never got to be a real violent hop, more of a shimmy.
I have some wheel spin when the tires were warm on dry pavement and oddly enough there was no bounce then.
About twice, Under hard acceleration I do think I experienced some 'power hop' where i felt a bounce when the tires were right at their limits of grip during 1st - 2nd gear pulls. But it never got to be a real violent hop, more of a shimmy.
Last edited by SuzukiDan7; 10-10-2011 at 03:29 PM.
#19
Le Mans Master
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I o9nly experienced wheel hop, many years ago when I first bought my Z.
I was practicing (hole shots) with new & original tires.
It's been so long ago, but looking back, I think I may have been coming out at too high of rpm's on the launch.
These Z's are real hard to launch.
I now save my hard launches with a good set of drag radials & after a good burnout in second gear. (at the drag strip)
No problems in many years now.
Oh & at the first opportunity I installed an ECS
(East Coast Supercharging) Trans/diff brace
I was practicing (hole shots) with new & original tires.
It's been so long ago, but looking back, I think I may have been coming out at too high of rpm's on the launch.
These Z's are real hard to launch.
I now save my hard launches with a good set of drag radials & after a good burnout in second gear. (at the drag strip)
No problems in many years now.
Oh & at the first opportunity I installed an ECS
(East Coast Supercharging) Trans/diff brace
#20
I've seen wheelhop caused mostly by-
1. Cold and or Wet roads.
2. Hard tires. Keep in mind that this is not only about which type of tires you are running but also the age of the tire. Old Tires = Hard Tires. Check your DOT codes if you're not sure.
I was 381whp NA with very similar mods to yours / now 550whp Blown and Loving It...
-My $.02.
1. Cold and or Wet roads.
2. Hard tires. Keep in mind that this is not only about which type of tires you are running but also the age of the tire. Old Tires = Hard Tires. Check your DOT codes if you're not sure.
I was 381whp NA with very similar mods to yours / now 550whp Blown and Loving It...
-My $.02.