175 BHP may be the claimed power output by Peugeot BUT this is measured at the flywheel normally on a testbed with a new engine in perfect running conditions.
On a rolling road you are measuring the power output at the driven wheels so you have to take into account power loss from frictional forces such as the gearbox diff and driveline wheel bearings etc. Also power steering pump alternator water pump drive belts will drain off power.
Also as the engine get older with more miles it becomes less efficent,
If you have only lost 20 bhp (PS) sound good to me.
Any good Peugeot dealer should aware of the above - would like to know what they did for £220!!
Maurice
February 2011