Davidthomas
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| posted on 20/1/14 at 09:51 PM |
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Car wondering/edging handling HELP
I wrote a post yesterday about my car wondering/feeling unstable at 40+mph. Some people wanted to know what caster/camber setting I had so here you
go..
Do this look ok??
[Edited on 20/1/14 by Davidthomas]
[Edited on 20/1/14 by Davidthomas]
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JAG
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| posted on 20/1/14 at 09:56 PM |
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OK - so in my experience a little toe-in at the front will make the car more stable in a straight line 
Justin
Who is this super hero? Sarge? ...No.
Rosemary, the telephone operator? ...No.
Penry, the mild-mannered janitor? ...Could be!
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unijacko67
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| posted on 21/1/14 at 01:07 AM |
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I'm not qualified to help, but where did you go to get that done and how much, wouldn't mind having a session.
http://www.kittenkitcar.co.uk
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Acc8braman
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| posted on 21/1/14 at 05:32 AM |
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Kwik fit now have the equipment to show this info 
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Ivan
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| posted on 21/1/14 at 06:40 AM |
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Assuming that +ve toe at the rear indicates toe out I would guess that the answer to your problem is to set up a little -ve toe at the rear.
Any toe out at the rear will cause instability and is a genuinely bad thing.
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Davidthomas
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| posted on 21/1/14 at 07:03 AM |
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Ok cheers
Is there any thing I can try regarding damping settings. I have avo adjustable shocks. Should the rears be softer than the front? Or the other way
round??
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steve m
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| posted on 21/1/14 at 07:14 AM |
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Have you tried different tyre pressures yet, as that would be the first thing to do, as per your other thread
Steve
Thats was probably spelt wrong, or had some grammer, that the "grammer police have to have a moan at
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40inches
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| posted on 21/1/14 at 08:32 AM |
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quote:
Originally posted by steve m
Have you tried different tyre pressures yet, as that would be the first thing to do, as per your other thread
Steve
Exactly, Geo isn't at all bad, but tyre pressures should be around 16psi all round, not 30psi rear 20psi front. Must be like driving on ice!
This question was answered in this thread http://www.locostbuilders.co.uk/viewthread.php?tid=188234
Have you lowered the pressures to 16psi yet?
[Edited on 21-1-14 by 40inches]
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britishtrident
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| posted on 21/1/14 at 08:46 AM |
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Toe-in is essential to stabilise the car Toe-in at the front stops the steering being hyper sensitive to inputs around the straight ahead position and
prevents the steering diving off line in response to unevenness in the road surface. At the rear toe-in reduces the tendency for the rear to go into
snap oversteer on entry to a corner. Toe-out at the rear is to be avoided at all costs.
At the front about 0.1 to 0.2 degrees across both wheels is about right, at the rear try 0.15 to 0.25 degrees should work.
Toe should should always beset with the car loaded with the drivers weight.
Because of the low weight compared to a tintop the dampers should be set at a soft setting.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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renetom
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| posted on 21/1/14 at 09:09 AM |
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wandering
Have you checked for bump steer ?.
Tyre pressures
Rear toe in
soften the shocks
all that's been already mentioned .
Good luck
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Not Anumber
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| posted on 21/1/14 at 10:52 AM |
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A small amount out here and there combined with the wrong tyre pressures can really affect the way these cars handle and feel on the road.
To be frank I didnt enjoy driving mine very much on the open road until:
The tyre pressures were reduced from around 30psi (tyre fitters!) to 16 psi
The fixed upper front wishbones were replaced with adjustables (steering self centring)
Indy Bird (knowledeable forum member) kindly set the suspension heights, damper rates, tracking, camber and caster.
Once these things were right it also dramatically reduced the amount of bump steer that previously been evident.
This work made a huge difference to the cornering and overall driveability of the car without spending very much at all.
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pewe
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| posted on 21/1/14 at 11:50 AM |
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Regarding shock settings - all things being equal the fronts should be set firmer than the rears.
On my other (hairdressers) car the MeisterR's are set two clicks firmer on the front but it may need more given the weight distribution on a
Se7en type car.
It was very noticeable that the car was washboarding at higher speeds when the adjustment was nearing equal.
Another consideration is whether the oil and valving in the dampers is set for a Se7en type car especially if it's live axle.
Matt at Procomp (on here) can dyno test coil-overs and advise the best set up.
HTH.
Cheers, Pewe10
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rodgling
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| posted on 21/1/14 at 12:30 PM |
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Disagree about toe-in being needed at the front, I have zero-toe at the front and I'm very happy with how that feels. Personal preference I
think, probably depends a bit on the car and how you use it too.
Toe-in at the back... I used to (unintentionally) have some toe out at the back. Going sideways around roundabouts was easy and fun but apart from
that I would not recommend this, as everyone else says, toe-in at the back is essential.
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Davidthomas
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| posted on 2/2/14 at 04:38 PM |
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Iv changed the tyre pressure to 16psi all round. Had a run out in it and it does feel better but still not fully planted.
I noticed that my rear shock were set pretty firm so iv put them to the softest setting but haven't got round to taking it out again.
I'm changing my wheels from 15" to 13" in the next month or so. I'll be fitting some yokohama A048s
Il see how it feels then.
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unijacko67
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| posted on 2/2/14 at 05:01 PM |
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The only time my car has been very unstable and I mean hard to even keep in one lane of the motorway, at speed I may ad, was when checked it had
excessive toe out (arround 6mm). I have found it to be good set at zero and also stable under braking. I had forgot to re-track the car after setting
the caster and camber (reason for it being so far out).
http://www.kittenkitcar.co.uk
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ashg
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| posted on 2/2/14 at 05:46 PM |
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its got to be the rear toe out causing the problem it needs to be -0.2 not +0.2 that means your nearly half a degree out on each wheel at the back,
that's going to have a big effect on the stability of the car.
I would be aiming to start with this
front
camber -1deg
toe anywhere between 0 and -0.5 deg (i run mine -0.2)
caster wants to be somewhere between +6 and +10 (if you want well weighted and good self centring on the steering) may be tricky to sort if you dont
have adjustable upper front wishbones
rear
camber -1deg to -1.2deg
toe somewhere around -0.2deg ( may be tricky to sort if you have no toe adjustment on the rear as it will either need shimming or new adjustable
wishbones)
tyre pressures around 15-16psi
rear ride height 15-20mm higher than the front with you in it.
if you fancy learning how to make a string computer you can play about with the settings yourself, you already know what the base settings are so you
can easily make adjustments to one thing at a time then go out for a drive and see how the car feels, you will very quickly learn what adjustment
does what.
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