(Reposted now the missing-all-images problem is fixed )
Rich Baron’s post about Honda’s CVCC engines focused on that technology as framed by enthusiastic actual, real engineer and president Soichiro Honda. Another auto executive had rather a different perspective.
General Motors’ CEO and chairman Richard Gerstenberg had risen through the ranks as a financials wonk, not an engineer, but he certainly didn’t let that stop him dishing out another helping of mark-of-excellence scorn on the cob: Well, I have looked at this design, and while it might work on some little toy motorcycle engine, I see no potential for it on one of our GM car engines, he said. Yep, another serving of the same old sh…stuff: haw haw haw, get a real car, haw haw haw.
Mr. Honda, who was nearing retirement, thought he’d check into Gerstenberg’s qualifications to be handing down engineering verdicts. A 1973 Chevrolet Impala was bought and flown to Japan, where Honda engineers rebuilt its 350 V8 engine as a CVCC item with new heads, intake manifold, carburetors, and so on. Then the car was flown back to the States for scrutiny at the EPA’s emissions and fuel economy test facility in Ann Arbor, Michigan.
The testing didn’t go perfectly; the small 1-barrel carburetor for the prechambers flooded due to float and inlet valve problems (oh, the good ol’ days; remember carburetors?). Even so, the results were the spanking Gerstenberg deserved at least as richly as those pre-chambers ran; the CVCC technique proved able to meet the U.S. 1975/76 hydrocarbon and carbon monoxide standards…yes, on one of Gerstenberg’s GM car engines! Oh, and there was no power penalty, and fuel economy was the same or a shade better. Tables III and V tell more or less the whole story; get the whole 13-page report as a PDF in a new browser tab by clicking this cover pic:
How do you say “In your face!” in Japanese? Not that it really matters; pretty good odds Gerstenberg wouldn’t’ve heard either the “boo” or the “yah” in English, either.
Ford and Chrysler didn’t share GM’s smugness, at least not on this particular question; they’re both said to have signed up to licence CVCC technology from Honda. As far as I know, Chrysler never did much of anything with it. Ford faffed around a little with it; Richard A. Johnson, in his book “Six Men Who Built the Modern Auto Industry”, quotes Soichiro Irimajiri:
“I was on an assignment to provide Ford with technical assistance about the CVCC engine. I worked side by side with their engineers, their R&D center, and then I went to […] personally observe the tests, which, incidentally, had many errors. I kept thinking what a difference there is in Ford’s management philosophy compared to Honda’s.”
To be sure, CVCC didn’t last very long in the market. It worked, but eventually couldn’t keep up with progressively tigtening emissions standards. Nevertheless, I don’t dismiss CVCC simply because the catalytic converter became the all-but-universal centre chunk of emission control systems. What Honda made a ’73 Chev 350 do without a catalyst—and, it bears repeating, without the miserable driveability; power loss, and greedier fuel consumption of Detroit’s methods—implies CVCC would have made for much cleaner exhaust, much sooner than we got it—with and/or without catalysts—on new cars through the ’70s and ’80s.
Old cars, too; think about what CVCC would’ve meant for the effective lifespan of catalytic converters on pre-1981 vehicles without feedback mixture control. As it happened, even when those cars were running properly, their exhaust was very dirty, which made the catalysts run very hot all the time, right on the ragged edge of meltdown, with scanty margin for anything to be out of adjustment. The much cleaner exhaust from a CVCC engine would’ve made life a lot less burdensome for catalytic converters.
Oh, well…I guess what was good for GM was good for the country, like it says in the Bible!