Panhard rods are a good thing in general, I should have said that explicitly
I guess. (even though you added a :-) it really may not have been clear.
Mini Mania sell those combo units (or did at one point) that connected to
the body
near the transnission tunnel. I could *never* recommend those units. I'll
just check their
web site.... Thats the same one. They call it Axle stabiliser. I'd go for
the Winner's
Circle unit instead or I think Tom Colby at Speedwell also sold one that was
good too.
I can't really remember Tom's (it was a while ago), but the Winner's Circle
unit has a
very good mounting system - it distributes the (significant) load through
the gas tank
mounting with a long attachment. This is quite important - I ripped holes in
the floor of
my first race midget with a inverted pyramid tubular structure (3 mounting
points in the
boot floor). You need to distribute this load!
Note that the Winner's Circle unit is not as long as a custom one can be,
but it
also works without affecting exhaust, handbrake etc straight out of the box.
(My bugeye
had the WC panhard rod fitted when I bought it).
Mike
----- Original Message -----
From "Elliott, Patrick" <patrick.elliott at attws.com>
To: "'Mike & Kerry Gigante'" <mikeg@vicnet.net.au>; <NewNGsInfo@cs.com>;
<spridgets@autox.team.net>
Sent: Tuesday, February 06, 2001 9:49 AM
Subject: RE: Rant on Panhard Rods (was More Tech Session Pics)
> So, with all that said. How do you really feel about them ? :)
>
>
> In all seriousness. I'm thinking about purchasing the one that Mini Mania
> sells for my '62 sprite. (1/4 elliptical).
> I've often rubbed a rear tire on the inside of the fender lips. While I
> realize that this isn't the ideal length, I don't have the time nor skill
to
> fabricate one myself.
>
> In your view would this item be good, bad or indifferent?
>
> -----Original Message-----
> From: Mike & Kerry Gigante [mailto:mikeg@vicnet.net.au]
> Sent: Monday, February 05, 2001 2:31 PM
> To: NewNGsInfo@cs.com; spridgets@autox.team.net
> Subject: Rant on Panhard Rods (was More Tech Session Pics)
>
>
> The most important principal behind panhad rods
> is to make them as long as possible - short ones can cause
> more problems than they solve.
>
> The "best" technique for horizontal location of solid rear axles
> is the Watts linkage. It works without changing the roll center
> height as a result of body roll.
>
> A panhard rod does cause a change in roll center height with
> body roll but the effect is dependent on the actual geometry.
> The goal is to minimise the change in this point:
>
> roll center = intersection of the longitudinal axis of the panhard
> rod and the centerline of the car (i.e. along the
> driveshaft)
> projected to the vertical plane passing through
> the axle housing.
>
> A short panhard rod does a poor job of mimising the variation! The
> longest rod you can make is the best because it minimises the change.
>
> Not only does the change in roll center adversely affect handling and
> predictibility (a) it is considered a bad thing to move the roll center
> above
> the axle b) the tendency of a car to understeer or oversteer is affected
> by the relative heights of the front and rear roll centers (among other
> things).
> In a stock spridget, the rear roll center stays at a constant height.
> c) jacking forces are introduced by panhard rods.
>
> With panhard rods the change in roll center is a non-linear function
> (sine) of the angle of the panhard rod (as distinct from the body).
> A short rod changes angle at a much faster rate (v body roll)
> than a long one. Therefore the roll center height changes further and
> more rapidly with a short panhard rod then with a long panhard rod.
>
> Finally, the angle of the panhard rod also results in a jacking force -
the
> force along the panhard rod projected onto the vertical plane. This is
also
> a function of the sine of the panhard rod angle. This jacking force can
also
> lead to evil handling traits. Note that the horizontal projection of that
> force
> is what actuall keep the axle located horizontally! The horizontal
> projection
> is constant for a given corner speed, therefore the compressive load along
> the rod and the vertical projection (jacking force) increases as the rod
> shortens.
>
> It should also be clear now why the combo anti-tramp rods/panhard rods
> are not a good design and why you should strive to make the panhard rod
> horizontal. If you are really fixed on handling, you also fit the panhard
> rod
> with an appropriate number of bags of cement sitting in the drivers seat.
> For some of thus, this makes a big difference (and is tiring work lifting
> all
> those bags in and out!!!!)
>
> OK, so how much difference does this all make? Not much if you don't
> push the car (but then why bother with the panhard rod in the first
place).
> If you are driving hard enough to *really* require a rod, then you will be
> seeing the adverse effects of a poor design.
>
> Mike
>
> ----- Original Message -----
> From: <NewNGsInfo@cs.com>
> To: <spridgets@autox.team.net>
> Sent: Tuesday, February 06, 2001 1:28 AM
> Subject: More Tech Session Pics
>
>
> > All,
> >
> > I have also posted some Tech. session pics at:>
> >
> > http://ourworld-top.cs.com/JCareyPage/news.html
> >
> > G'day
> > John Carey
> > http://ourworld.cs.com/JCareyPage/JCareyPage.htm
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