Our December issue will feature a story by Associate Editor Scott Ross, which deals in part with how federal and state regulations have shaped the development of the Corvette over the years. The following excerpt was drawn from that article.
Think back to 1975, when Federal emissions standards kicked in that led to the use of catalytic converters. Those highly expensive devices—which helped boost the ’75 Corvette’s base sticker price by $800 over the ‘74’s MSRP—were said to help performance by taking the burden of nearly a mile of vacuum lines and other emissions-control hardware off the engine. They “helped performance” by doing that while clogging the exhaust system with a single-unit, two-way catalyst that turned unburned hydrocarbons and carbon monoxide into CO2 and water vapor. The single-unit cats led to major inefficiencies in exhaust-system design, which limited horsepower and torque while getting emissions down to the new Federal limits.
That’s something that more than a few ’75-’82 C3 Vette owners have discovered—especially the ones who’ve removed their cats for an exhaust that’s up to track-day duty, or replaced the OEM two-way cats with current-technology three-way cats (which add the transformation of nitrogen oxides to nitrogen and oxygen to the two-way cats’ functions).
All the while during the late ‘70s, the engineers that worked on Corvette’s powertrains were doing the best they could (under the circumstances) to find at least as much power in the venerable Chevy small-block V-8 as it has produced during the ‘60s. The real breakthrough came with the development of microprocessors to control engine functions that were up to the job of operating in the hostile environment of an engine bay. Add in improvements like roller rocker arms, improved cylinder-head and exhaust-system designs, and electronic fuel injection, and the “old” engine eventually cranked out the power like it had before—but this time, with fewer emissions per mile.
In the early ‘90s, The General’s powertrain engineers (who’d been merged, realigned, and otherwise moved from their previous divisional engine shops) were challenged to design and engineer a new V-8 that would exceed the previous GM V-8s’ performance numbers while meeting ever-stricter Federal emission and CAFE standards. The result was the LS-series of engines, whose performance you know well by now—and whose fuel economy, especially at highway speeds, you’re also well aware of.
But now, stricter CAFE and emission standards loom on the horizon. Per Federal regs enacted in 2009, manufacturers must meet a fleet average of 35.5 miles per gallon for all the cars and light trucks they sell by the year 2016, up from the current 27.5 mpg. Those vehicles not meeting the standard will be subject to a “gas guzzler tax” added to the sticker price. What we’ve heard is that the next-generation Corvette engine, while still a V-8, might only displace 5.5 liters (around 330 cubic inches).
If there’s one thing the Corvette team has done in recent years, it’s been to use cutting-edge technology to meet the Feds’ fuel-economy and emissions standards while delivering the level of performance expected of a Corvette powerplant. Whether they can continue to do that in the face of ever-tightening economy and emissions standards, however, remains to be seen.