Jaguar's XK Coupe will get the company's new 3.0-litre diesel engine but the Convertible will not.
Sources haven't confirmed when the new engine will be fitted to the Coupe, or which of the 3.0-litre units will be used.
There are 204bhp and 272bhp versions, but the more powerful 'S' engine is tipped for the XK.
Meanwhile, Jaguar has denied that it is working with Lotus on a new front-engined roadster and coupe.
Our sources say that Jaguar is developing a Porsche Cayman/Boxster rival based on the XK platform in-house.
It will have an all-aluminium body and may be powered by a V6 version of the XK's V8 engine. Our sources also deny taht Lotus is involved in the project.