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Hard to get in 3rd gear when lose traction on 2nd gear. r34 gtr

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Hard to get in 3rd gear when lose traction on 2nd gear. r34 gtr

Hi. I got this change gear problem from my last happy lap.

My car is 660hp r34 gtr, I lose traction badly everytime when I floor it on 2nd gear from 5000rpm. At the same time the gear stick shaking very bad.  It's AWD OMG:(

The gear shift and car drive all good normally but if I floor it 2nd to 3rd is hard to get in gear and sometime I miss shift to 5. I know it's about my skill. But it's really hard get the right position when the gear stick shake like crazy. 

I already got nismo engine and gearbox mount.  So my question is what I can do to make the gear stick stable on 2nd gear? And it wasn't that bad before maybe I got bad traction this time?

i think change better tyre will help (I have nitto invo)any other idea?

 

 

GTSBoy Grand Master

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Axle tramp occurs when the combination of spring + damper + tyre sidewall stiffness + tyre grip + bush deflection + chassis twist all add up to cause the rear suspension to compress as the tyre grips under power and then as the tyre reaches the point of breaking traction the sudden reduction in compressive force in the suspension causes it to pogo upwards.  As it comes back down it loads the tyre over and above the load it gets just from weight + torque reaction, increasing grip.  So it hooks up, loading the suspension more until it pogos again.  Rinse and repeat.

The R32 rear end is particularly prone to it due to the geometry.  The 33s and 34s less so, but they're not immune.  2 cars that seem to be set up identical will have one do it while the other one doesn't.

It ultimately comes down to springs and dampers, getting them right.  If really stiff then it never grips properly and just breaks traction.  If really soft, it compresses heaps and doesn't rebound (drag style).  Somewhere in the middle is better performance overall, but also somewhere in the middle is axle tramp territory.  And then all those other factors I listed at the top stick their beaks in too.

Fixing it is hard.  My car axle tramps like a bitch and I've never been able to fix it, through 3 different sets of dampers and springs.  Different tyres have affected it more than anything else.

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thank

4 minutes ago, GTSBoy said:

Axle tramp occurs when the combination of spring + damper + tyre sidewall stiffness + tyre grip + bush deflection + chassis twist all add up to cause the rear suspension to compress as the tyre grips under power and then as the tyre reaches the point of breaking traction the sudden reduction in compressive force in the suspension causes it to pogo upwards.  As it comes back down it loads the tyre over and above the load it gets just from weight + torque reaction, increasing grip.  So it hooks up, loading the suspension more until it pogos again.  Rinse and repeat.

The R32 rear end is particularly prone to it due to the geometry.  The 33s and 34s less so, but they're not immune.  2 cars that seem to be set up identical will have one do it while the other one doesn't.

It ultimately comes down to springs and dampers, getting them right.  If really stiff then it never grips properly and just breaks traction.  If really soft, it compresses heaps and doesn't rebound (drag style).  Somewhere in the middle is better performance overall, but also somewhere in the middle is axle tramp territory.  And then all those other factors I listed at the top stick their beaks in too.

Fixing it is hard.  My car axle tramps like a bitch and I've never been able to fix it, through 3 different sets of dampers and springs.  Different tyres have affected it more than anything else.

great info!! thanks a lot! i will get the suspension checked one day, but i don't think anything wrong with it. if they are all good, I will get better tire, but i worried some better tire will make it even worse.  because the day without too much axle tramp the tire feel normal, but the day with a lot axle tramp the tire feel a little sticky. both day i run same setup. 

maybe some really sticky tire will fix this problem. 

 

I don't really feel the car shake  , but the gear knob shake badly. i just worried i will damage the gearbox one day cause the axle tramp:(

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