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Location:
S.E suberbs, Vic
Registered:
December 2003
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Location:
c'town, NSW
Registered:
May 2002
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Re: Savage Understeer
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Wed, 17 November 2004 01:30
 
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u have to ask mechanic kittah not me man
i totally agree with u
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Location:
S.E suberbs, Vic
Registered:
December 2003
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Re: Savage Understeer
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Wed, 17 November 2004 01:32
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hehehehe I got to get me one of those!
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I supported Toymods
Location:
Sutho/Hills NSW
Registered:
September 2002
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Re: Savage Understeer
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Wed, 17 November 2004 02:32
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mechanic kitteh can be hired if your in need
its only a small fee but the diagnosis he does is unbelievable.
upon purchase mechanic kitteh may not arrive, no refund, if DOA buyer must pay all legal fees.
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I Supported Toymods
Location:
Perth
Registered:
May 2004
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Re: Savage Understeer
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Wed, 17 November 2004 03:21
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could someone plz explain to me how making the rear shocks stiffer makes the car more neutral if its already oversteering?
i would of figured more squat on the rear during cornering = more weight = more traction = less oversteer?
thats why people put shocks out of other cars into the rear of sprinters when they set up for drift
anyways chopping springs is more then acceptable if u match the shocks to trap them and cut your bump stops shorter
just dont get caught by the poolice
anyways Bobski passes around a peace pipe "why cant we all just get along" 
Adam
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Location:
S.E suberbs, Vic
Registered:
December 2003
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Location:
South Australia
Registered:
July 2002
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Re: Savage Understeer
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Wed, 17 November 2004 06:43
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Oh my god how I hate 'my car handles like a 60 year old in bed' threads.
For starters driving style has *alot* to do with perception of handling characteristics. I *hate* trying to set the car up for others especially when they give feedback like "ohh it understeers" or "ohh it oversteers". Then I hate it even more when people say "this car has 'natural' oversteer" because it's a ridiculously over-simplified statement. Most people assume that because they can get the car to oversteer that they are hardcore, thus if they mention oversteer in a handling debate then everyone will gasp in awe at their skillz.
Unless you want to give more details about *exactly* how it handles then I will assume that you are too shit a driver to really know what good handling is, and you should just lower it stick some really expensive swaybars, springs, shocks, 17inch mags and a strut brace on for 'torsional rigidity' (people will assume you are smart when you say that) and you will probably believe that it handles awesome and most others will agree with you (for no reason at all).
If you actually do want more information go read a book on vehicular dynamics or go out to the racetrack with some adjustable suspension and sort it out in your head by trial and error and learn that way.
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Location:
Terrigal
Registered:
May 2002
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Re: Savage Understeer
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Wed, 17 November 2004 06:50
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Can I recommend Fred Phun (spelling?) How to make a car handle.
Old book, but good.
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Location:
South Australia
Registered:
July 2002
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Re: Savage Understeer
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Wed, 17 November 2004 06:52
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| Quote: |
could someone plz explain to me how making the rear shocks stiffer makes the car more neutral if its already oversteering?
i would of figured more squat on the rear during cornering = more weight = more traction = less oversteer?
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Not quite right there. Shock absorbers are designed to damp the motion of the spring, thus they are part of the system that controls the RATE of weight transfer, not the actually amount of weight transfer itself. If you have two way adjustable shocks, for example, and you increase the damping on bump then you may find that the weight transfer to the outside wheel during the beginning of the corner will be more tolerable and thus less likely to cause oversteer (in the hands of the not-so-subtle corner entry type of driver). Of course this is dependent also on how the fronts behave, and how the sway bar plays it's roll and what kind of rebound damping you have on rear (as unloading the inside tyre too quickly could also cause loss of traction). I'm just saying that 'stiffening' the shocks does not necessarily increase the amount of weight transferred, but it does affect the transition.
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Location:
Canberra, ACT
Registered:
September 2002
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Re: Savage Understeer
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Wed, 17 November 2004 08:56
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| FWDboy wrote on Wed, 17 November 2004 17:43 |
For starters driving style has *alot* to do with perception of handling characteristics.
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dood, plz! All Toymods users are clones of Fangio and G. Villeneuve here! Insult our driving at your peril!
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Location:
Campbelltown
Registered:
November 2003
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Re: Savage Understeer
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Wed, 17 November 2004 09:06
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Another comment that should be told is that majority of cars are built to understeer look at new commodores they just fattened up the anti roll bars to make them understeer more. Understeer is genrally safer in the arms of an amature anyway, it is a lot easier to control than oversteer. Understeer is easily quelled by easing off the throttle and gently applying the brakes yet oversteer has to be controlled and any sudden adjustments will see the car snap and throw you back the other way. my car oversteers for no apparent reason nothing to do with driving style just slightly wet roundabout when I go straight through them, when weight shifts as you straighten up to exit the roudabout the steering lightens up and the rear can be seen to wonder, even at ridiculously low speeds it still happens, to me it would be nicer to have understeer.
on the road however you shouldn't really experience understeer or oversteer to much for that matter, generally it just means your driving like a tool outside the limits of the car and the laws of physics.
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Location:
cambo
Registered:
May 2002
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Re: Savage Understeer
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Wed, 17 November 2004 09:12
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HOW TO MAKE YOUR CAR HANDLE BY FRED PUHN hp books great book i still got it
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I Supported Toymods
Location:
Perth
Registered:
May 2004
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Re: Savage Understeer
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Wed, 17 November 2004 13:18
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hmm
ok maybe what i should of said would go something like this
the initial force of one powering out of a corner shifts weight to the rear....with soft rear shocks the rear squats = more weight = more traction = less oversteer
you are right in what you say that its the rate of transfer but not correct on how this affects springs
this happens because the initial force is what decides how a car moves through a corner, the car keeps its rear down because the car is accelerating and the springs are already compressed...they dont have the ability to push back because the weight is already there and constant from acceleration and from the sudden weight transfer
with stiffer shocks...in that time frame where the weight shifts the shocks take the force and slow it...therefore the force on the springs acts over more time....with less force...therefore the car doesent squat = all the opposites of the above
thats why stiffer shocks increase oversteer...
so you are right in what you say but stiffer shocks do increase oversteer
and im not Villeneuve im fekin keitchi 
on a serious note the more cash u spend on stuff the better it is, a set of coilovers will most probably fix all or any dramas 
besides your wifes / girlfriends / mums complaining about you spending so much money on your car (cant live with em cant kill em  jk)
Adam
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Location:
South Australia
Registered:
July 2002
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Re: Savage Understeer
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Thu, 18 November 2004 01:19
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| Bobski wrote on Wed, 17 November 2004 23:48 |
hmm
ok maybe what i should of said would go something like this
the initial force of one powering out of a corner shifts weight to the rear....with soft rear shocks the rear squats = more weight = more traction = less oversteer
you are right in what you say that its the rate of transfer but not correct on how this affects springs
this happens because the initial force is what decides how a car moves through a corner, the car keeps its rear down because the car is accelerating and the springs are already compressed...they dont have the ability to push back because the weight is already there and constant from acceleration and from the sudden weight transfer
with stiffer shocks...in that time frame where the weight shifts the shocks take the force and slow it...therefore the force on the springs acts over more time....with less force...therefore the car doesent squat = all the opposites of the above
thats why stiffer shocks increase oversteer...
so you are right in what you say but stiffer shocks do increase oversteer
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You tool! For one thing you are talking about a completely different form of oversteer. Secondly, the equillibrium point where the spring will 'rest' during cornering in 90% of cases is totally unaffected by the shock rate (unless you course the time spent in the corner is short enough that the spring/damper system doesn't reach an equillibrium). If you don't understand why, look at the mathematical model of the situation - it will explain it reasonably well.
What is particularly wrong in your statement is when you say "the force on the spring acts over more time...with less force..." - so where the hell did the force from the acceleration of the vehicle go? The only other thing it can do is act on other springs etc - but it definitely CAN'T disappear. So the force applied to spring is definitely not altered by the damping rate. Okay some force is dissipated as heat due to friction in the shock absorber's fluid (viscosity) - but this is a VERY small amount, which is generally considered to be negligible except if the heat in the shock absorber is likely to be a reliability factor (for example the safari rally)
Stiffer shocks on bump may cause a more rapid transition to oversteer out of a corner, but causing *more* oversteer (ie greater slip angle at the rear) might only occur if the surface is particularly rough.
If you REALLY want to change the characteristics of the chassis, start with sway bars, springs, DIFFERENTIALS, torsional strength, and most of all WHEEL ALIGNMENT as the shape of the contact patch throughout the corner is quite important in changing the handling character of a car. Or alternatively we could all realise that we aren't on a race track and we could shut up.
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Location:
South Australia
Registered:
July 2002
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Re: Savage Understeer
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Thu, 18 November 2004 01:31
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Oh yeah back to my example, let's say the driver is reasonably rough at the wheel and ditches it into the corner pretty hard, alot of weight is tranferred to the outside wheel, if it's transferred at a really high rate, it could cause the spring/damper system to go straight past equillibrium and into the realm of semi-oscillatory behaviour - this is how it can cause oversteer, the weight transferred to the outside is not really 'tolerable' (in my words) and causes oversteer as the spring bounces back (towards equillibrium) - in this case a stiffer shock on bump would have been desirable as it would have maintained a more stable system.
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Location:
Tasmania
Registered:
May 2002
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Re: Savage Understeer
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Thu, 18 November 2004 02:37
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This is very interesting to me, but I disagree which half of what has been said, mostly towards the top of the list...
I have a standard AE86 Sprinter. I am going to make a webpage listing all exact measurments of the suspension on the famous AE86. And will attempt to explain exactly why the AE86 handles like it does. I think alot of it is to do with bump steer, or toe deviation with suspension travel at the front. Also the angle of the rear 4 links effectively can give a little rear-steer action. RCA blocks are something you may want on a lowered car, but most people don't realy understand how or why they work. Its very complex. I believe RCA blocks would be a refinement, not a cure to a big problem.
I think my standard Sprinter feels very neutral. You can drive it hard around a corner with very little steering movement and it just goes where you steer it, mostly. I wouldn't say in natrualy understeers, not compared to other cars. I have had my stock AE86 around a race track, and even with 4AC-open diff, I was sweeping the corners with controlled oversteer.
My car: AE86 Sprinter
new shocks, cheap
polyurathane bushes, most joints
stock springs, 13" wheels
about 3 degrees caster, stock camber
zero toe-in
no strut brace or anything like that
The car now needs a locked or 2-way diff
I don't think there is much wrong with chopped springs. People that scare you against it don't give much explanation. And those are the people that shouldn't chop springs because they don't understand how far to go. I would sooner chop my springs than waste money on new lowered ones, but then again I don't want to lower my car realy that much. A chopped stock spring will have a stiffer rate, in theory, but the difference is very small. The chopped spring is still soft, as are most lowering springs. The height does not matter much to me. If I was buying different springs, it would be for a stiffer rate. I will be buying 6kg/4kg/mm springs sometime soon. But soft springs does not equal bad handling, depends on the tyres you have.
Whitchy: Maybe you should try RCA blocks and a wheel alignment. You want toe in at about zero, and its probably toed in too much now if it understeers. The RCA blocks will change the bump steer and reduce understeer.
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Location:
Tasmania
Registered:
May 2002
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Re: Savage Understeer
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Thu, 18 November 2004 02:46
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Also, lots of caster will not make the car twitchy, it will make it more stable. Caster is a good thing, as long as the steering is not too heavy for you.
And, a thicker front anti-roll bar (anti-sway bar to some) will make it understeer more. I believe to get the full benifit of the AE86 suspension design, you want to let the car roll a bit. I'm still thinking about this. Standard anti-roll bars should be ok, unless you have sticky race tyres.
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Registered:
February 2003
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Re: Savage Understeer
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Thu, 18 November 2004 02:48
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Very informative Jonny, will be interesting to read your tech articles on the ae86 frame
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I Supported Toymods
Location:
Perth
Registered:
May 2004
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Re: Savage Understeer
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Thu, 18 November 2004 02:49
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yeah jonny is right..fit some rca's they make a huge difference to hard driving over bumpy roads
and FWDBOY the force is absorbed by the shock absorber as on a stiffer setting it wont go in quiet as far therefore the rear doesent squat down as much....geez how many times do u want me to say this before it gets through ur thick skull, what the hell are u rambling about safari and deserts and shit...geez..
its a simple fact...with stiffer rear shocks the force aplied by the car powering out of a corner cant push the springs down as far because the shocks resist more....with the rear heigher the weight is more even then with the weight more rearward therefore less traction.........thats all im saying .... stop going round and round in circles...its yr 8 physics for gods sake
maybe in FWD cars it works different ill give u that much but i wouldnt know....i prefer not to ever drive a horse and carriage style arangement where im pulled about
Adam
(namecalling geez must be way too early in the mornin.....sips his coffee  )
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Registered:
February 2003
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Re: Savage Understeer
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Thu, 18 November 2004 02:51
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Location:
South Australia
Registered:
July 2002
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I Supported Toymods
Location:
Perth
Registered:
May 2004
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Re: Savage Understeer
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Thu, 18 November 2004 03:35
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here plz use my sword....
on another note...check out this funny
(ive had my coffee and smoke now so im happy, deepest apologies fwd boy)
A woman sitting at a restaurant in McKinney, Texas suddenly began to
cough while eating a giant country-fried steak. After a few seconds it
became apparent that she was in real distress, and two cowboys at the
next table turned to look at her.
"Kin ya swaller," asked one of the cowboys? The woman signaled 'No',
desperately shaking her head. "Kin ya breathe?" asked the other. The
woman, beginning to turn a bit blue, shook her head 'No.'
> >>> > >>
With that, the first cowboy walked over to her, lifted up the
back of her skirt, yanked down her panties, and slowly ran his tongue up
>and down the woman's butt crack. This shocked the woman into such a violent
spasm that the obstruction flew out of her mouth and she began to
breath again.
> >>> > >>
The cowboy slowly walked back over to his table and proudly took another
drink of his Lone Star beer. His partner said in admiration, "Ya know,
I'd heard of that there Hind Lick Maneuver, but I ain't never seen
nobody do it."
if this is inapropriate i also apologise
Adam
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Location:
Baulko Hillo
Registered:
April 2004
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Re: Savage Understeer
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Thu, 18 November 2004 03:40
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| FWDboy wrote on Thu, 18 November 2004 12:19 |
You tool!
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So if Bobski's comment about your thick skull is dodgy, what's the above?
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Location:
South Australia
Registered:
July 2002
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Re: Savage Understeer
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Thu, 18 November 2004 03:46
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It's called 'jest' as I assume bobski's comments are also laden with 
Talk about nit-picky!
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Location:
Baulko Hillo
Registered:
April 2004
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Re: Savage Understeer
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Thu, 18 November 2004 04:30
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| FWDboy wrote on Thu, 18 November 2004 14:46 |
Talk about nit-picky!
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I Supported Toymods
Location:
Perth
Registered:
May 2004
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Re: Savage Understeer
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Thu, 18 November 2004 09:39
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bah
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Location:
South Australia
Registered:
July 2002
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Re: Savage Understeer
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Thu, 18 November 2004 16:10
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meh - if you are anything like me you can't even afford to think about improving handling these days
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