Westport Announces Fourth Quarter and Year End Conference Call for May 27, 2004

VANCOUVER, British Columbia--May 20, 2004--Westport Innovations Inc. (TSX:WPT) announced today that it will disclose its fiscal fourth quarter and year end financial results on May 27, 2004. To coincide with the disclosure, Westport has scheduled a conference call for Thursday, May 27, 2004 at 8 am (Pacific Time).

After the formal presentations, Westport will accept questions from analysts and institutional investors. The public is invited to listen to the conference call in real time or by replay. To access the conference call by telephone, please call 1-877-563-8311 no later than 7:55 am on May 27, 2004. Alternatively, the webcast of the conference call can be accessed through the Westport web site at www.westport.com by following the link on the Investor Information menu. Replays will be available in streaming audio shortly after the conclusion of the conference call.

Westport Innovations Inc. is the leading developer of gaseous fuel engine technologies. It develops, manufactures and sells a wide range of engines for commercial transportation applications such as trucks and buses through Cummins Westport Inc., its joint venture with Cummins Inc. Technology development alliances are in place with a number of other leading engine manufacturers, including Ford, MAN, Isuzu, and BMW to develop engines that operate using cleaner-burning fuels such as natural gas, propane, hydrogen, and blended fuels such as HCNG.

Note: This document contains forward-looking statements about Westport's business, operations, technology development or to the environment in which it operates, which are based on Westport's estimates, forecasts and projections. These statements are not guarantees of future performance and involve risks and uncertainties that are difficult to predict, or are beyond Westport's control. Consequently, readers should not place any undue reliance on such forward-looking statements. In addition, these forward-looking statements relate to the date on which they are made. Westport disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.