Re: stiffening spiders

[Alan Lambert <gerard@domain.elided>]

I'm afraid Chris is speaking on a subject of which he is ignorant. First, 
the stiffener does not bolt to the floor pan, Second a friend of mine who 
is a competent Alfa racer drove my Spider through only a couple of 
corners at some speed (on the street) before he asked me "do you have a 
stiffener installed?" He asked because the car was so much more rigid 
than Spiders usually are.

I'm not trying to flame, but I have a problem with inaccurate advice 
being send the the list, some of whose members will believe it.


On Tue, 29 Jun 1999, Chris Prael wrote:

> > From: Jack Nasielski <jackn@domain.elided>
> > 
> > There must be a few people who have tried the spider chassis stiffener.
> > Please share your experiences.  Did you install it yourself?  Who
> > supplies these things? (I saw one in the centerline book for $425).
> > 
> > thanks-
> > jack
> 
> I have never tried one of these, nor would I!  They are a shuck.
> 
> If you much about structures, it should be obvious that any "bolt-on"
> device will add a lot of weight and do very little stiffening.  
> 
> It is simply a matter of leverage.  Alfa already built extra weight
> into the floor of the 105/115 chassis to stiffen the Spider.  Any
> structure that you bolt to the floor pan will have an even worse
> strength-to-weight ratio.  
> 
> You can produce a useful improvement in torsional stiffness by careful
> design of a roll cage that is welded to the car. But the car will be a 
> single seat race car, not a street machine.
> 
> These chassis stiffeners probably make great ballast, but that will not
> improve the car's performance.
> 
> Chris Prael
> 
> 

================================================================================
Regards,
Alan G. Lambert___________________________________<gerard@domain.elided>
           *******Los Altos, California (office)*******

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