Ford Ecoboost 3.5 liter V-6 engine

Ford Ecoboost 3.5 liter V-6 engine: V-8s may go the way of the Dodo - at least in Ford and Lincoln vehicles. The automaker has developed a new line of direct-injected and turbocharged V-6 engines designed to produce V-8 horsepower and torque output while maintaining the fuel economy of a smaller V-6 engine.

Ford is concerned about the prospect of gas prices going back to $3 or $4 per gallon - in which case, vehicles equipped with gas-guzzling V-8s will become as hard to sell as Betamax VHS players. In addition, the federal government recently passed a law which will require all new cars to average 35.5 miles per gallon by 2016 - which is just a few short model years down the road from now. V-8s are thus becoming a liability - but many customers still want V-8 power and performance. Ford hopes its Ecoboost concept will solve this dilemma.

Direct injection optimizes combustion efficiency and also permits the use of very high compression ratios for high power output without engine knock, because the high-pressure fuel charge reduces internal cylinder temperatures. The result is a 20 percent increase in efficiency compared to an otherwise similar engine without direct fuel injection. Turbocharging, meanwhile, boosts low-end torque and also provides on-demand power for merging and passing at higher speeds. In the new Lincoln MKS sedan, the 3.5 liter Ecoboost engine returns 17 mpg in city driving and 25 on the highway - while producing 355 horsepower. In contrast, Ford's workhorse 4.6 liter V-8 (used in everything from Mustangs to Explorer SUVs) produces 40 less peak horsepower (315 in the Mustang GT) while managing only 16 miles per gallon in city driving and 24 miles per gallon on the highway.

Ford plans to offer its line of Ecoboost engines in fully 90 percent of its vehicles by model year 2013.