Reply to: As ye plough, so shall ye reap
[ Lotus West trivia question.... who was responsible for the original L/W =
tech tip,
[ which was published many years ago, under the above subject / title???
Howdy, Steve, Marty, All.
Marty, I've forwarded this message to Chapman-era as well, because I =
suspect
that they will find this question thoroughly interesting!
Marty Wilson wrote:
>>I am after some feedback on setting up the front suspension of my =
Amaroo
>>Clubman.
Steve White replied:
>The original Lotus used the front antisway bar for locating the top of
>the front upright. At some stage it was changed (around the series 3 or
>4 ... or maybe it was a Caterham change) to an upper and lower wishbone
>setup with a separate antisway bar. How does the Amaroo have its front
>suspension arranged?
Marty Wilson wrote:
>>I have only run it in hillclimbs so far and the "turn in" on the =
corners
>>doesnt seem too famous, it tends to understeer. I have been advised to =
dial
>>in more negative camber and this will cure it.
>>I will be running in a supersprint ar Amaroo in Sydney shortly so I =
would
>>be interested in feedback on front suspension setups that work for =
other
>>Lotus 7 replica style machines
Steve White replied:
>What sort of adjustments do you have available to you? Camber, caster
>and toe? How much adjustment is possible? What sort of tyres are you
>running, what size and how old are they? What pressures do you normally
>run in them? What sort of compromises are you prepared to live with?
>.... for instance you might improve the turn-in and make the car really
>responsive to steering input, but that might make the car really 'darty'
>and tiring to keep in a straight line.
Good questions, one and all. Particularly the bit about tire pressures! =
First
step, before you assume that suspension adjustments are necessary, oughta =
be to simply increase the front tire pressure or decrease the rear =
pressure a
bit, assuming you have not already done this..... If they are more than =
5 psi
different already, you may be justified to adopt more serious measures.
Marty, does it only push when you're trying to get it to turn in, or does =
it push in
steady state cornering as well?
If it pushes all the time, then more negative camber at the front *might* =
be a
wise approach, but assuming it is already set somewhat negative, you =
would
probably sacrifice braking.... still, that could prove worthwhile =
overall, for tight
courses. Everything is a compromise as Steve pointed out.
You oughta first try diddling the anti-roll bar settings. Does it have a =
rear bar?
If so, start by adjusting it slightly stiffer.
Best bet though, might be to begin by getting some tire temperature test =
data,
to tell you whether the camber is in the ballpark to begin with at the =
front, and
how the roll stiffnesses are presently set up, before you actually start =
adjusting
the camber or the anti-roll bar settings.
If it only pushes when you're trying to get it to turn in, then before =
more radical
measures, first consider just using less toe-in at the front. Depending =
on the
course, and your driving style, you oughta be able to get away with much =
less
toe-in than you would use on the street. Change it a little bit at a =
time, tho =3D:-O
Other comments?
This oughta be an interesting thread!
erik.berg@trw.com
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