Autos: Blow-By Blow

Four months ago, as part of his crusade against smog, Abe Ribicoff, the Secretary of Health, Education and Welfare, served the auto industry with a blunt ultimatum: unless the auto manufacturers agreed to install blow-by* anti-pollution devices on all 1964 models voluntarily, the Administration would ask Congress to compel them to do so. Last week the automakers went Ribicoff one better, decided to make blow-by devices standard equipment on all their 1963 cars and light trucks.

Blow-by devices fight smog by piping the smog-making gases that collect in the crankcase back through the intake manifold to be burned in the cylinders. To ease the eye sting in Los Angeles, the nation’s smog capital, Detroit last year equipped all new cars to be sold in California with a blow-by device made by General Motors’ A.C. Spark Plug Division. G.M.’s blow-by, which is the only one approved so far by California’s Air Pollution Control Board, added from $4.50 to $6.50 to the price of the ’61s that carried it. Since longer production runs will cut manufacturing costs, the blow-bys used on the ’63s may come even cheaper. To keep them cheap, all the auto companies are apt to go on using the G.M. device rather than incur the tooling-up expenses involved in making their own.

But as automen were quick to point out, blow-by devices are no cureall. Much of the air pollution in the U.S. is produced by industry rather than cars. And even in cars, less than 40% of the smog-producing hydrocarbons comes from the crankcase. The major menace is exhaust fumes, which so far can be controlled only by expensive (upwards of $75) “afterburner” attachments.

*Blow-by is Detroit’s name for the unburned fuel vapors that escape from the cylinders of an internal combustion engine during the compression stroke. From the cylinders, the fuel enters the crankcase, where its hydrocarbon-rich fumes mingle with the vapors from hot engine oil, then slip out through a vent into the surrounding atmosphere.