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  #41  
Old 14-06-2006, 10:31 AM
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That's more a 4WD trait.
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  #42  
Old 14-06-2006, 05:57 PM
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i run 36 front and 35 rear on 215/45/R17 (goodyear eagle f1 gsd3).

with front and rear pressures set equal ive encountered a gear backlash type noise in the drivetrain when changing from 3rd to 2nd. dropping rear pressure by 1-2psi helped reduce (pretty much eliminate) this noise.

anyone else noticed similar?
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Old 16-06-2006, 10:28 AM
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Quote:
Originally Posted by SilentKilla
Im also worried that too high a rear pressure may induce snap oversteer when you come off throttle, or the snap back of doom i see some subi's do in vids when they stack it.
This is kinda what I was trying to refer to in previous post. A lot of people (both 4WD and FWD owners) that I've seen tend to love to jack up the rear stiffness so much, it induces huge and erratic lift off oversteer. They swear by it, claiming the car 'handles better', when in fact they're probably losing just as much pace/ time through a corner as they were innitially with understeer! This has as much to do with HOW they are driving into corners as their suspension setup as well.

The lift off oversteer IS a 4WD/ FWD trait. It occurs once again due to the slip angles dramatically changing at that moment that you lift off the throttle. This occurs due to the driven wheels (or larger bias driven wheels in the case of 4WD- Subie's have slightly more power through front wheels) suddenly losing the engine force that was acting on these tyres and creating a larger slip angle of distortion... resulting in a momentary samller angle on the front tyres. The rear tyre slip angle remains the same at that point of cornering and therefore becomes larger than the angle of the front tyres for that short period. This induces momentary oversteer, that depending on how much speed you are also carrying at the time can lead to major or minor havoc! (... and a bounty of tank slapping?).

The trick is learning to drive smoothly. If you choose to lift off, lift off gradually.. if you choose to accelerate, accelerate gradually etc. The best way to nail this (and be told if you aren't!) is joining one of these training days that Alex has recently been promoting.

Last edited by subarooboy; 16-06-2006 at 10:31 AM.
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