twr owner tom walkinshaw commissioned a one-off model in 1996 for his ownership based on the aston martin db7. the car was fitted with a 6.4-litre jaguar-twr v12 engine based on a 6.0-litre v12 engine. the engine had a revised steel crankshaft and specially designed four-valves per cylinder heads. the twin cam-shafts worked by a unique chain drive mechanism. the engine has a claimed power output of at 6,000 rpm and of torque at 4,500 rpm.