The Plymouth Pronto Spyder was a 2-door roadster concept car revealed in 1998. It never went into production, partly because of the discontinuation of the Plymouth brand, but largely because it was meant as a rolling test of styling and mechanical concepts.

The car was fitted with a mid-mounted, turbocharged, 2.4 L, 225 hp (168 kW), 4 cylinder engine, later used in the Chrysler PT Cruiser, and a five speed manual transmission. It was designed to mimic the feel of more exotic European roadsters, but partly by using lightweight recycled materials (largely polyethylene terephthalate, or PET, covering a steel chassis) in its construction, cost much less; the vehicle weighed 2,700 lb (1,225 kg). The interior was also a styling test-bed for color (it was spray-painted red) and instrumentation arrangements.

Aside from the engine, the plastic tortoise-shell steering wheel rim was later used (on the Chrysler 300C. To be produced, the concept would have needed to meet safety regulations, have better body stiffness (the A-pillar would need revision), suspension travel clearance for the wheelhouse, and rear-view mirrors, among other changes.
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