The Plymouth Pronto Spyder was designed to help renovate the Plymouth brand by going back to basics: bringing back Plymouth’s “value for price” mantra, with an affordable high-performance car.
We test-drove the Pronto Spyder concept car in 2004; after we drove it, the designer took it out and opened the throttle wide - something we hadn’t dared to do, given the hand-built nature of most concept cars - and it moved radily. Even without pushing it, the power of the SRT-4 engine came through clearly.
The steering was firm and tight, the center of gravity low, and the suspension firm, for a fun and stable feel. The driver was in a traditional low sports-car position; it was easier to get into and out of than the Sling Shot, and about even with the Toyota MR2. It feels as though it would be more enjoyable (and comfortable) than the MR2, and feels as though it can deal with zigzags more easily. It was too narrow for everyday use; we’re had to move out of the way of the stick, as did our slender passenger.
The Pronto Spyder did indeed wear a Plymouth badge, along with a rare sight in modern cars (and common in the 1970s): a friendly, warm, deep red which works quite well, though the fact that it was spray painted was fairly obvious up close. The metallic surface on the instrument panel was also used extensively in the beautiful Chrysler Chronos; the wheel ended up looking better than the production 300C wheel. The odometer was painted on.
Engineers tried to keep the Spyder affordable without hurting quality, by spending less on materials and more on engineering. Thus, the extensive use of polyethylene terephthalate (PET), also used in soda bottles; the idea was to make the Plymouth from recycled materials. PET technology could cut manufacturing costs by 80%. The chassis is still high-strength steel.
When it was first shown, the engine must have been seen as pie-in-the-sky: the 2.4 liter dual-cam 225-horse powerplant, mounted behind the seats. The Spyder was designed to drive like an exotic sports car, helped by a low center of gravity and 18 inch aluminum wheels with 225/40 tires and a five-speed stick.
Debuting on the Pronto Spyder was a plastic tortoise-sheel steering wheel rim, used on the 2004 300C, and chrome accents. The idea was to show what it would look like with paint pigments directly injected into the plastic, using silver and red spray paint.
Weighting in at 2,700 lb, the mid-engined, rear-wheel-drive Pronto Spyder was probably capable of 0-60 times around 5.5 seconds.
To go on sale in the US, the Spyder would have to meet crush rules, gain body stiffness (the undercut A-pillar hurt it there), increase suspension travel clearance in the wheelhouse, and, of course, have an inside mirror. Its high-mounted door handles, which we saw in the 1980s with the Chevrolet Berretta and in the 2000s with the Jeep Patriot, worked well.
See our main concept cars page.
Concept cars are often made so a car’s feel can be evaluated, problems can be foreseen, and reactions of the public can be judged. Some concepts test specific ideas, colors, controls, or materials — either subtle or out of proportion, to hide what’s being tested. Some are created to help designers think “out of the box.” The Challenger, Prowler, PT Cruiser, and Viper were all tested as production-based concepts dressed up to hide the production intent.
Concept cars • popular: Firepower • Tomahawk • ME412 • Mighty FC • Gladiator
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