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I Supported Toymods
Location:
south Melbourne/KL
Registered:
June 2004
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stupid Q on 4wheel alignment
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Sun, 12 December 2004 05:57
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why is it that newer cars allow alignment on the rear wheels? with older cars we only needed align. on front wheels. what is the reason for allowing rear wheel alignment?
off the top of my head, so we can adjust the toe for racing setup on the rear??
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Location:
Newcastle, Hunter Valley
Registered:
January 2004
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Re: stupid Q on 4wheel alignment
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Sun, 12 December 2004 06:16
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i belive its because of IRS...........I think
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Location:
On your mum!
Registered:
May 2002
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Re: stupid Q on 4wheel alignment
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Sun, 12 December 2004 06:17
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Most modern cars are equipped with independent rear, and the toe and camber will change with the normal wear of components.
This seems like a likely reason - I am not 100% sure though.
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I Supported Toymods
Location:
south Melbourne/KL
Registered:
June 2004
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Re: stupid Q on 4wheel alignment
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Sun, 12 December 2004 06:58
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| alex_ta22 wrote on Sun, 12 December 2004 17:16 |
i belive its because of IRS...........I think
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IRS?
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Location:
Newcastle, Hunter Valley
Registered:
January 2004
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Re: stupid Q on 4wheel alignment
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Sun, 12 December 2004 07:12
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IRS - independent rear suspesnsion', basically what yellorolla said. Because the suspension is now independent like the fronts, the same rules apply i guess
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I Supported Toymods
Location:
south Melbourne/KL
Registered:
June 2004
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Re: stupid Q on 4wheel alignment
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Sun, 12 December 2004 08:49
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i thought the front needs alignment because its the steering wheel. rear wheels dont steer. (apart frm 4ws).
anybody got definate answer?
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Location:
The Eastwood MASSIVE !
Registered:
May 2003
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Re: stupid Q on 4wheel alignment
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Sun, 12 December 2004 09:01
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Obviously introduction of IRS has lead to it alot , but then again it comes down to manufacturers and commonsense.
It makes sense that both rear and front wheels be adjustable , when accelerating and braking the alignment changes , and also as bushes and componants wear down , but have yet to need replacing , wheel alignment is slightly off. Having fully adjustable front and rear allows to keep the car with a optimium alignment for handling and safety at all times.
Some of the older cars I have worked on , even ones that had IRS did not have any adjustments at the back wheels , and only toe at the front. My cars has rear camber adjustment and front toe adjustment , all the rest are preset from factory with the bushes and control arms ect ect , but as the bushes wear my alighment will move out slightly unless I replace bushes.
However the new cars I work on , have lots of goodies , like 5 link rear suspension setups and castor , camber and toe adjustments on front and rear. It's mainly due to progress of technology.
20 years ago it was easier to make suspension systems with factory set alignment on everything but toe at the front. Now days totally alignable systems are easily and cheaply manufactured onto lots of models of cars.
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Location:
Tasmania
Registered:
May 2002
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Re: stupid Q on 4wheel alignment
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Sun, 12 December 2004 14:56
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I do a fair few wheel alignments. If I give a simple answer, it won't make propper sence.
When ever I do a wheel alignment, its always a "4 wheel alignment" in one sence, in that I clamp the measuring devises to all 4 wheels. Some laze people only clamp the things to the front wheels.
With a live rear axle (all RWD corollas, HiLux, Hiace, Cruiser etc) there is no way you can adjust toe. Its welded set in one position (and not always zero toe by the way). But idealy you want a bit of toe-in on the back, for stability. And with IRS, its a less robust setup, and more corrections need to be done after a crash.
For tyre wear, toe in is the most critical adjustment. Mostly on the front. But if you can adjust the back also, you have more chance of getting the car to run straight with even tyre wear.
But don't talk about caster on the rear, you will confuse yourself. I don't believe there is a caster angle on the rear.
I could go on...
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