Does depends on alot of variables - not least how it's driven but also the condition of the engine; given that these engines are over 15 years old now.
This was a 600 mile round journey 60-70 mph on the way there and 60mph on the return journey, using ~55L of petrol on a 20vt, I could of managed better if I hadn't encountered rush hour traffic.

The engine is in very good condition though and has been completely rebuilt - head and bottom end. It has more or less completely bedded in now and the car itself weighs in at 1100 kg (+/-20kg)