Ferdie:

I was told that the Mk.1 Elise used several Aluminium parts that were replaced by siblings in steel on the Mk.2 version, primarily for economical reasons.


 

Already the S1 had a steel rear frame (and a steel roll over hoop). During production of the Elise, Lotus had tried with an all aluminum subframe but they had found out that it would crack under excessive load during durability tests, so they switched to simple steel frame for rigidity and that solved the problem.


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