Home  
Site Partners: SpotterGuides Veloce Books  
Related Sites: Clubmans Rallycross Your Link Here  

Go Back   TenTenths Motorsport Forum > Other Motorsports > Rallying & Rallycross

Reply
 
Thread Tools Display Modes
Old 18 Jun 2010, 13:42 (Ref:2714312)   #1
boyracer
Racer
 
Join Date: May 2002
Location:
western australia
Posts: 153
boyracer should be qualifying in the top 10 on the grid
Subaru WRX breaking rear traction

Just wondering if anyone else wants to lend weight to this theory.
The other weekend a driver I was servicing for ended his rally with the WRX in the trees. A fast right 2 corner, nose in and everything seeming fine when all of a sudden the rear seemed to lose traction with the usual result of running wide, touching the trees and game over.
Nothing much thought about it, driver is compotent driver, though perhaps not as familar with a 4WD as some (most of his dirt racing being FWD, mostly tarmac with the 4WD) and was pushing hard, so easy to ignore.
Just watched some coverage on the national championship over here and another driver who ended in the trees, seemed to have the same explanation for his excursion into the trees. This time a tighter right hand, though still fairly quick. Same unexpected break away in the rear end. This in a completely different part of the country on a vary different rally.
Just wondering if perhaps we're missing something that the rest of the rally world is already aware of ? I know one of the local manufacturers teams used to rewind the electronic centre diff for a stronger engagement.
Not sure if both teams were running the same suspension ?
Maybe nothing, but thought I'd ask
boyracer is offline  
__________________
Happiness is seeing the race ....... in your rear view mirror
Quote
Old 18 Jun 2010, 19:11 (Ref:2714450)   #2
mountainstar
Veteran
 
mountainstar's Avatar
 
Join Date: Dec 2003
United States
Posts: 6,885
mountainstar should be qualifying in the top 5 on the gridmountainstar should be qualifying in the top 5 on the gridmountainstar should be qualifying in the top 5 on the grid
I think it's more a vehicle dynamics issue than anything mechanical.

A couple of things:

1. The driver was simply going too fast for the corner and exceeded the grip limit of the tires.

2. The driver lifted off the gas suddenly causing throttle off oversteer, weight shifted to the front, the rear tires get light and the car starts to rotate. In rally this can be facilitated by the camber of the road or changes in grip on the road surface.

3. The driver was too hard on the throttle causing throttle on oversteer. When you accelerate weight shifts over the rear tires and too much power along with the curvature of the road can cause the rear tires to break grip and the rear of the car starts to rotate.

4. The drivers eyes were focused on the outside of the corner rather than on the road. Hands and feet follow the eyes.

2WD and 4WD have some differences but it doesn't change the fact weight transfer happens in a vehicle and whatever tires that were on the car are only going to have a certain limit of grip.
mountainstar is offline  
__________________
Wolverines!
Quote
Old 18 Jun 2010, 20:47 (Ref:2714485)   #3
BertMk2
Race Official
Veteran
 
BertMk2's Avatar
 
Join Date: Mar 2003
United Kingdom
Nr Maidstone, Kent
Posts: 10,276
BertMk2 is going for a new world record!BertMk2 is going for a new world record!BertMk2 is going for a new world record!BertMk2 is going for a new world record!BertMk2 is going for a new world record!BertMk2 is going for a new world record!BertMk2 is going for a new world record!
I'd agree - driver error is the most likely cause, too much speed carried into the corner (followed by a mid corner lift) or too soon on the throttle coming out of the corner seem likely.
BertMk2 is offline  
Quote
Old 18 Jun 2010, 21:51 (Ref:2714513)   #4
tbtstt
Veteran
 
tbtstt's Avatar
 
Join Date: Jan 2008
United Kingdom
Redhill, England
Posts: 3,707
tbtstt should be qualifying in the top 5 on the gridtbtstt should be qualifying in the top 5 on the grid
I have heard of some Subaru drivers complaining (or rather being a little unsure) of the DCCD when left in "Auto" mode. Not sure whether rally cars run with this switched on though - or if your car even has it!

As has been said though, I suspect its more likely a dynamic issue rather then a mechanical one.
tbtstt is offline  
Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
2006 Subaru Impreza WRX STI - Ken Block cg7aa Video Clips 1 4 Dec 2008 23:49
ACO 2004 Rear Diffuser vs. Toyota Eagle MkIII GTP Rear Diffuser Dauntless ACO Regulated Series 10 16 Jul 2003 21:21
On the lookout for a Subaru Impreza WRX Spudgun Road Car Forum 9 21 Mar 2003 08:25
WRX Experience elephino Road Car Forum 7 3 Nov 2002 10:07
2000 WRX GB plans announced Andy H Rallying & Rallycross 2 16 Mar 2000 20:36


All times are GMT. The time now is 15:55.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Original Website Copyright © 1998-2003 Craig Antil. All Rights Reserved.
Ten-Tenths Motorsport Forums Copyright © 2004-2021 Royalridge Computing. All Rights Reserved.
Ten-Tenths Motorsport Forums Copyright © 2021-2022 Grant MacDonald. All Rights Reserved.