Japan's Honda Motor Co Ltd has again produced the most fuel efficient and least polluting vehicles on American roads, the U.S. government projections for 2009 showed on Friday.

South Korea's Hyundai-Kia and Toyota Motor Corp, also based in Japan, followed closely behind, respectively, for the second straight year, according to preliminary performance data released by the Environmental Protection Agency (EPA).

Overseas automakers mainly sell compacts and sedans in the United States, while their U.S. rivals produce more pickups, SUVs and vans, which generally get poorer gas mileage and emit more tailpipe emissions.

Honda and Toyota also lead the U.S. market in gasoline/electric hybrid vehicles, the most fuel efficient and cleanest cars sold.

Total fleetwide average fuel efficiency is estimated to be virtually unchanged at 21 miles per gallon for the 2009 model year. Carbon emissions output inched down overall.

Honda's fleetwide fuel efficiency is projected to be 23.6 mpg. That would be slightly lower than the performance last year, EPA said. Honda's emissions output also ticked up slightly.

Hyundai-Kia vehicles are expected to post a 23.4 mpg rating this year, down incrementally from 2008, while Toyota rolls in at 23.2, up a bit from last year. Hyundai-Kia's emissions output moved up slightly while Toyota's fell.

The top performer from Europe was Volkswagen AG, which placed fourth out of the nine global manufacturers analyzed. Its fleet efficiency is projected at 22.8 mpg, up half-a-point from last year. Volkwagen's emissions were unchanged.

U.S. automakers will show some improvement this year, but still lag behind their Asian and European counterparts in mileage and cleaner engines.

Chrysler, which heavily features a lineup of pickups, vans and SUVs, ranks last for emissions. Chrysler also projected to fall further behind in fuel economy at 18.7 mpg, again placing last in the annual rating in both categories.

Ford Motor Co and General Motors Co [GM.UL] both boosted fuel efficiency and lowered emissions this year, with Ford expected to register the bigger gains. Ford cars and trucks are set to average 20.5 mpg, while GM posted a 19.9 rating, the figures show.

Both Chrysler and GM restructured in bankruptcy this year.

(Reporting by John Crawley; editing by Andre Grenon)