Wow, right? Two failed Chevrolet sports coupes in less than a week? OK, so the Cosworth Vega was the more special of the two, but you can see how they tried to learn from their mistakes when—again—trying to address the problem of losing more and more young buyers to the imports.
First, instead of partnering with an outside firm, the X-11 package was done completely in-house. And for the first year, it consisted of a few suspension modifications (sway bars, optional V6 engine, better tires, and shorter gearing)…in addition to cosmetic dress-up items. For its next model year, 1981, the car had significant performance improvements…
…but all of it was on top of a pretty dim car.
There's no other way to slice it. In a New York Times profile of Alan Spiegel, (likely) the world's only X-11 enthusiast, Spiegel admits to the car's various faults:
“[The odometer] could have been 30,000 or 130,000…It’s hard to tell with these cars, because they aged badly and quickly.”
"The plastic was junk…It would break down from sunlight and turn chalky white and then disintegrate."
“But I think it’s the only reason the headliner didn’t fall in. It’s held up by the sunroof frame.”
"It’s a computer-controlled nightmare…The man who rebuilt the engine actually worked on these engines in the factory, and even he said he couldn’t do much more for it."
Spiegel's car was even of the best year for the X-11. Even better suspension, an upgraded 2.8-litre V6 engine, performance exhaust, rear spoiler, different gear ratios, fibreglass hood with functional(!) air intake.
With 135 horsepower and 165 lb-ft of torque on tap, they'd do 0-100 km/h (0-62 mph) in about 8.5 seconds. Chevrolet learned from the Cosworth Vega in another area as well. Instead of taking a racing motor and adapting it for street use, why not take a street car fully support a racing programme?
Bob McConnell drove a 1981 X-11 to SCCA Showroom Stock B championships in 1982 and 1984, the X-11 lasting only a year longer. From 1981-1985, roughly 20,500 full-strength X-11s rolled off the assembly line.
Within General Motors, the X-11's development helped launch the career of John Heinricy, the company's performance vehicle guru.
An effective performance car, sure. It's just a shame it was based on the Citation. It's a good thing GM has been giving Heinricy better platforms to play with these days…