LUCRA CARS

[rossybee]

Is that a GTM Libra? Nifty wee things

[BiggestNizzy]

Stiffer chassis than the elise ....really?

"The core of Libra is a tub-like chassis weighing just 98kg and yet has a torsional stiffness of 14,000Nm/degree, which compares with 68kg and 10,133Nm/degree for a bare Elise chassis. The suspension mounted to it was specially designed for the Libra by specialist engineer Bryn Davies."

really

[Shug]

Stiffer chassis than the elise ....really?

"The core of Libra is a tub-like chassis weighing just 98kg and yet has a torsional stiffness of 14,000Nm/degree, which compares with 68kg and 10,133Nm/degree for a bare Elise chassis. The suspension mounted to it was specially designed for the Libra by specialist engineer Bryn Davies."

really

Not actually that tough in that it's a pretty heavy fibreglass monocoque with a roof to aid that rigidity. Was there ever a convertible? Did they give rigidity figs for that?

[rossybee]

http://www.diseno-art.com/encyclopedia/ ... pyder.html

[Shug]

Cool so what that tells me is that there was a convertible, it did lose rigidity, for which they had to re-engineer the tub section to replace some of that, also adding another 30KG. Also, that link doesn't mention whether the re-engineering did manage to recover all the rigidity from the lost roof (most major manufacturers don't manage it, even when adding lots more weight and bracing - a roof is a really convenient brace for a structure)

End of the day, the Elise platform was revolutionary when it comes to strength vs weight. You can make anything stiff by adding material. The base Libra chassis may have been a percentage stiffer than the Elise, but it was also the same percentage heavier (more or less)

Given the base Elise tub only needed different subframes to be used as part of a GT1 car (to fit the engine and front suspension) I don't think anyone has ever said it's not stiff enough for purpose

The Libre is definitely not to be added to the vast list of awful kit cars though, was a really nicely engineered thing and probably deserved more acclaim than it received.

[rossybee]