Coach builders Dennis also made a model called a Javelin for a while, available in two chassis lengths for an 11m or 12m body, both powered by the famous Cummins 8.3 litre turbo-diesel straight-six engine, tuned for either 211 or 240 bhp, with masses of torque.  This picture is from an old sales brochure.

If anyone out there has driven one and can let me know the 0-60 and quarter-mile times and confirm or correct my 10 miles-per-gallon figure, I'd be grateful!  Not the sort of info. that's easy to come by really.