Spot the give away. Four big exhaust pipes where there is usually two. These four exhaust pipes signify that this is Jaguar’s forthcoming premium XF model which will probably wear the XF-R moniker.

Jaguar"s current XF line-up includes 2.7L V6 diesel, 3.0L V6 petrol, 4.2L V8 petrol and a 4.2L supercharged V8 petrol. The majority of these models have received much praise from the motoring press with Jaguar’s XF bettering many of its German rivals in test comparisons. Not bad for a manufacturer on the ropes.

The jury is still out on what will power the premium XF although it can probably be narrowed down to two options. A rework of the current 4.2L supercharged engine is not out of the equation, in its current guise it is good for 416bhp and a prodigious 560Nm of torque. In isolation, these figures appear to be more than sufficient, however the Germans are regularly pumping 500+hp now out of the super saloons. It must also be noted that the SV8 XF is equipped with this very engine so customers will be expecting something special for the R model. The basic architecture of the 4.2L V8 is traceable all the way back to the 4.0L unit first introduced in 1997 so it is getting on a bit now. It is therefore debatable whether Jaguar engineers can wring any more horsepower out of this ageing powerplant.

This leads to the second and more probable option. Jaguar and Land Rover have jointly been working on a replacement for their V8 engines for some time now. Rumour has it that a number of Land Rover models have been spotted with "upgraded" engines recently. This engine is likely to be a Direct Injection petrol V8 of 5.0 litres in capacity. As Land Rover use reworked versions of the Jaguar V8 in its models, it would be fair to assume that both manufacturers will be receiving this new DI 5.0. This unit should be good for 500hp in supercharged form.

The waters are murky for Jaguar and Land Rover at present as they are about to be sold to Indian Industrial giant Tata. As a result, many future programs may well be on hold. However if all bodes well after the sale completion, we can expect the XF-R model debut at the London motorshow this summer followed by a station wagon/estate and a possible convertible.