datsun-roadsters
[Top] [All Lists]

Re: front end geometry

To: a roadster list <datsun-roadsters@autox.team.net>
Subject: Re: front end geometry
From: Toby B <toby@wolfenet.com>
Date: Sat, 06 Nov 1999 01:30:33 -0800
Calvin Grandy wrote:

>         Inspection has shown  that the wishbones of the front suspension are 
>"swept back" about 10 degrees from perpendicular to the direction of travel.   
>what does this geometry contribute to handling or cornering stability / power? 
> Is it just an assembly of parts, or is there a method?

If you re-eyeball it, you'll find that the trailing a-arm pivot lines up
with the ball joints.  As to method, ?  It does make the front
suspension into a slight trailing arm, doesn't it?

> Is the small change in A-arm location associated with suspension deflection 
>part of some design, or are the threaded "end bearings" just a useful way of 
>distributing axial loads on the A-arm spindles?

It's a brilliant copy of a wacked British design on the TR4.  The slight
movement fore and aft is way too small to make any handling difference. 
One benefit, tho, besides having your a-arm pivots wear out in 500 miles
if you don't grease them, is that it's a really low-defelction design-
those metal bushings have zero compressability!

> Has anyone modified the front steering system to provide anti-Ackerman 
>geometry as is consistent with present day tire performance?  

The stock design does have Ackerman-angle compensation built in. 
Hmmm... if the slip angle goes up on both tires (theory being that
modern tires have greater operating slip angles) would that change the
Ackerman angle much?  Wouldn't seem to...
(Ackerman angle is the technical term for "inside tire has to turn into
a corner more as it's radius around the turning point is smaller than
that of the outside tire')


Hmmm, again, on a similar topic- how much bump-steer is built into the
stock suspension?

Toby

<Prev in Thread] Current Thread [Next in Thread>