Thanks Stewart this has also perplexed me and the lack of any readily available
ball park figure tells me this is in the area of take a stab, build in adjust
ability where possible so if you find you have built a monster you can try to
minimize the problem. It's fine if you are building a rock crawler or drag car
you could build in heaps to suit.
Cheers
Ian
On 25 February 2020 at 17:18 "Stu718 ." <stewart.collinson@xxxxxxxxx> wrote:
This topic caused me anxiety. Not so much antidive as my car's trailing
front arms don't give me too much control over this.
The question for me, with a surplus of power, rear weight bias and a
double wishbone rear, was antisquat under acceleration .
The conundrum was that weight transfer under squat is good for straight
line performance and the stoplight grandprix but maybe not so good for
exiting Manfeild hairpin.
Factors I considered were c. o. g height and front to rear weight dist.
My car is 60/40. But I didnt know what a good starting point for anti
dive/squat was and nor could anyone or any book really tell me. At the very
least I had to be sure that the rear wishbone geometry didn't toe under
squat.
I opted for a trivial amount of antisquat... about 0.5degrees. And sure
enough my car squats like a motorboat under acceleration.
In the end i rationalised my choice (a) I wasnt a good enough driver
anyway and (b) I could make later adjustments via ajustable dampers and
overall srpimg setting.
Cheers Stewart
On Tue, 25 Feb 2020, 12:04 Ian Johansen, < ijohansen@xxxxxxxxxx
mailto:ijohansen@xxxxxxxxxx ;> wrote:
> >
Thanks Brian,
will do some more study tonight your comment on low centre of
gravity for sports/racing cars seems relevant.
Thanks for your help
Ian
> > > On 25 February 2020 at 10:55 Brian Worboys <
brianworboys@xxxxxxxxx mailto:brianworboys@xxxxxxxxx ;> wrote:
>
Here's a couple of interesting reads. I also note that for
low centre of gravity sports/racing cars, there is also an argument for
zero or very little anti dive because anti dive also affects the
suspension rate and related handling properties. You pays your money
and you takes your chance :-)
https://suspensionsecrets.co.uk/anti-squat-dive-and-lift-geometry/ ;
http://wedgelist.triumphwedgeowners.org/suspension/04_anti_dive/Wedge_Antidive.htm
Cheers, Brian
On Tue, 25 Feb 2020 at 09:17, Ian Johansen <
ijohansen@xxxxxxxxxx mailto:ijohansen@xxxxxxxxxx ;> wrote:
> > > >
Thanks Mike it is double wishbone.> >
Ian
> > > > > On 25 February 2020 at 09:09 Mike
Macready < m.w.macready@xxxxxxxxx mailto:m.w.macready@xxxxxxxxx ;> wrote:
> > >
Hi Ian,if it is double wishbone suspension I seam
to recall 1.5 deg. comes to mind. However you didn't tell what type
of suspension you have? Attached is the section from race car
dynamics. Mike.
On Mon, Feb 24, 2020 at 9:19 PM Ian Johansen <
ijohansen@xxxxxxxxxx mailto:ijohansen@xxxxxxxxxx ;> wrote:
> > > > > >
Hi all,> > > >
I'm in the process of designing/building
the front suspension on my GTO project and while I can find how to
measure/set the anti dive component nowhere can I find what is a
ball park amount to dial into the design as it's not easy to make
this adjustable. Can anyone offer a resonable figure?
Ian Johansen
Nelson
> > > > >
