VANCOUVER, B.C. — Westport Innovations says it has improved the performance of its flagship HD15L LNG engine.

The natural gas engine is offered in Class 8 Kenworth and Peterbilt trucks.

Improvements include an increase in horsepower and torque, to 550 hp and 1,850 lb.-ft. torque. The new ratings have been offered in Australia for several years, Westerport says, and have accrued more than 10 million kilometres of service. The new rating will be available in early 2013, according to the company.

Westport also announced availability of the Eaton UltraShift Plus automated manual transmission in Kenworth and Peterbilt configurations.

The engine is also compatible with 16,000-lb front axles on the Peterbilt 367, expanding the vocational applications it’s suited for, Westport announced.

And the engine will also feature an optimized emissions equipment system, tailored for the lower emissions profile of natural gas, which will reduce cost and weight while lessening user intervention, Westport claimed.

“These product enhancements are in direct response to requests from customers that operate their trucks in the most demanding of applications, and further validate that Westport’s HD15L natural gas engine offers diesel-like performance in any environment,” said Clark Quintin, president of Westport HD. “We are building on our established leadership in technology development to deliver improved horsepower, torque, and fuel efficiency using low-cost natural gas, and are ideally situated to respond to the demands of the marketplace.”

Westport says its HD15L gas engine is currently in use in 14 US states and four Canadian provinces as well as Australia.