If you have registered and paid your BARC membership you should be getting sticker decals later this week.
For clarification here is how to calculate your power to weight figure for our class structures.
5 litres of fuel equates to approximately 4.5kg (900g per litre).
Divide 1000 by weight of car inclusive of driver and fuel, then multiply that figure with engine flywheel power. Then the total is your power to weight figure.
Car weighs 500g, driver 85kg and fuel 4.5kg. Total weight = 589.5kg
1000 divided by 589.5 = 1.696
Power of car = 185bhp at flywheel
Multiply 1.696 X 185 = 313.8 power to weight ratio
Hope this helps. But don't worry about getting it exact the class structure is designed to be approximate and we certainly do not want you running off down the dyno road. We wish for the entrant to be honest, you all know your engine specification, thus power. However, we may check weight at some point especially if one car disappears off into the distance from other class competitors. Its all about having some clean honest competitive fun.