Humbug
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| posted on 21/10/05 at 06:47 AM |
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Advice on suspension setup please
I've just passed my SVA  for which I had:
- about 3 turns of TRE toe out
- front springs up fairly high
- the adjustable shocks set to the 8th softest click (out of about 23) all round
- tyres at 20psi
- camber is more or less vertical (as measured with a block of wood and a spirit level - nothing fancy)
Like that it seemed like I had to make quite a conscious effort to get the steering to turn - nothing dangerous, it just didn't have very quick
reactions
Since SVA, I have wound down the springs so the TREs are more or less level, and wound the TREs in to have 2 turns of toe in. In this setup, the
steering seems a bit twitchy, i.e. wanders when I don't want to turn.
I could just set it up so I have less toe in, but I was looking for opinions and what other people have done in terms of camber, toe in, springs,
shocks, tyre pressures, etc. (front and rear if different).
FYI, at SVA the axle weights with nobody in the car were 270kg front and 288kg rear, if that makes any difference?
Thanks in advance
[Edited on 21.10.2005 by Humbug]
[Edited on 21.10.2005 by Humbug]
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Surrey Dave
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| posted on 21/10/05 at 08:26 AM |
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I have my tracking set parrallel (only with the string round car method at home!), Camber set at 1 - 1.5 degrees neg , dampers 7of 23 front , back 4
or 5 of 23 , tyres about 18 psi , the car can still be a bit nervous over uneven surfaces but overall not bad............
[Edited on 21/10/05 by Surrey Dave]
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NS Dev
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| posted on 21/10/05 at 08:48 AM |
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off the top of my head for a non-specific car surrey dave's setup would be my start point, sounds about right on everything.
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Humbug
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| posted on 21/10/05 at 09:36 AM |
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Thanks Dave. I'll try these settings out.
btw, I am sure that it's mentioned somewhere else on the forum, but humour me and tell me which way does negative camber lean? In at the top of
the wheel or out?
Cheers
quote:
Originally posted by Surrey Dave
I have my tracking set parrallel (only with the string round car method at home!), Camber set at 1 - 1.5 degrees neg , dampers 7of 23 front , back 4
or 5 of 23 , tyres about 18 psi , the car can still be a bit nervous over uneven surfaces but overall not bad............
[Edited on 21/10/05 by Surrey Dave]
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iank
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| posted on 21/10/05 at 10:09 AM |
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http://www.answers.com/topic/camber-angle has a clear diagram and some discussion on camber.
Top in is negative.
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David Jenkins
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| posted on 21/10/05 at 10:16 AM |
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I have zero camber, and zero toe-in, and it works well for me. However, a suspension book I have (written by Des Hammill, I think) recommends 1
degree negative camber and 1 degree toe-out for seven-style cars.
Although the toe-out sounds wrong, it's supposed to assist turn-in on corners. The down-side is that the more toe-out you have, the more
'exciting' the car will be under severe breaking. That's what the author says, anyway - I can add no comment except that I
haven't tried these settings!
rgds,
David
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Humbug
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| posted on 21/10/05 at 04:35 PM |
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quote:
Originally posted by David Jenkins
...Although the toe-out sounds wrong, it's supposed to assist turn-in on corners...
I have read that toe out assists self centring and that is what I had on my car for SVA. If that is true, then it would seem that toe-in, not
toe-out should assist turn-in on corners???
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David Jenkins
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| posted on 21/10/05 at 04:41 PM |
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It's something to do with assisting the ackerman angle that most cars don't have properly set up!
At this point I bow my head and admit ignorance of car geometry...
David
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westf27
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| posted on 21/10/05 at 05:52 PM |
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interested in this this string around car method of setting track,can anyone explain?
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BKLOCO
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| posted on 21/10/05 at 08:55 PM |
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I was always taught that basic tracking set up was as follows:
Rear wheel drive cars:
0 - 1 Deg Toe Out.
Front wheel drive cars:
0 - 1 Deg Toe In.
Experience is what you get when you don't get what you want!!! 
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BKLOCO
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| posted on 21/10/05 at 09:03 PM |
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String method Tracking
String method
Wrap a piece of string round all four wheels on the C/L of the wheel. Measure the gaps between the string and the front tyres (Either at the front of
the wheel or the back but the same place each side) add the measurements of each side together and divide by 2. You can then use Trig to work out the
tracking angle.
Experience is what you get when you don't get what you want!!!
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britishtrident
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| posted on 22/10/05 at 10:58 AM |
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Try lowering the tyre presure on the front to 16 psi put 18psi in the rears.
Always adjust the toe setting after setting ride height and camber.
RWD car parrallel or slight toe in on front
Fwd cars should normally toe out on front.
At rear IRS always set up with a slight toe-in unless using semi-trailling arms then set up with lots of toe-in.
Front camber for road use -0.5 to -1.5 degrees for track use -1.0 to -2.0 degrees.
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Rorty
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| posted on 22/10/05 at 01:00 PM |
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quote:
Originally posted by BKLOCO
I was always taught that basic tracking set up was as follows:
Rear wheel drive cars:
0 - 1 Deg Toe Out.
Front wheel drive cars:
0 - 1 Deg Toe In.
I think you've got things a bit mixed up there.
Toe out on the rear of a RWD car will accentuate oversteer and FWD cars are almost without exception set to toe out because of the tendency of the
driven wheels to fight the bushes and pull in.
Cheers, Rorty.
"Faster than a speeding Pullet".
PLEASE DON'T U2U ME IF YOU WANT A QUICK RESPONSE. TRY EMAILING ME INSTEAD!
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BKLOCO
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| posted on 22/10/05 at 10:05 PM |
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Bugger......
I just read my post and realised I got it completeely the wrong way round.
My excuse is I had just finished a week of early shift and was "dog tired" (no pun intended).
Thanks for pointing out my error Rorty LOL
Experience is what you get when you don't get what you want!!!
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