There are two cars with an aluminum chassis and SMC bodywork.

This is the Corvette chassis:

http://www.sae.org/servlets/dlymags/....jpg&alttxt=C7 Corvette structure.jpg

http://www.sae.org/servlets/dlymags/....jpg&alttxt=C7 A-pillar detail.JPG

Then this view shows the one-piece frame channel from front-suspension-to-rocker-panel-to-rear-suspension actually tieing into something bigger at the rear:

http://www.youtube.com/watch?v=wkgYxM7vT3k

And then this link explains the concept of bulkheads (castings) holding frame rails (and this is how Ferrari's, Lamborghini's, recent production Ford GT's, and Audi R8's are built and also how carbon fiber tubs work):

http://www.sae.org/mags/aei/11744/

This link explains the SMC bodywork:

http://media.gm.com/media/us/en/gm/n..._corvette.html

This link explains why SMC bodywork is only 30% lighter than steel bodywork:

http://www.compositesworld.com/artic...automotive-smc

Here is the Lotus Evora chassis:

http://gglotus.org/blog/wp-content/u...a-chassis1.jpg

Here is a link that suggests the Evora as a race car platform:

http://evorainfo.net/FileStore/PDFs/...nglePages).pdf

Here is a link that suggests the Corvette as a race car platform:

http://www.corvetteracing.com/cars/g...ckground.shtml

Here is a link to the SRT Viper which has a steel chassis and then bodywork of carbon fiber, aluminum, and SMC:

http://www.allpar.com/cars/viper/2012-dodge-viper.html

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