For only the fourth time in F1 history, every starter finished Sunday's European Grand Prix in Valencia. Williams battled hard to bring its cars home just outside the points, with Rubens Barrichello in 12th and Pastor Maldonado 18th.

Technical director Sam Michael looks back at the weekend

AT&T Williams took several upgrades to Valencia. How effective were they?
We had a new rear wing in Valencia which we raced with. We also took a new exhaust system but we decided not to run this before qualifying. Having reviewed the practice and race data, we now plan to run the revised exhaust system again at Silverstone.

How did the new engine mapping freeze affect the team's performance in qualifying?
It restricted some of the changes we would normally make, but it wasn't our first order.

Rubens was second fastest through the speed trap in qualifying. What conclusions can be drawn from that?
Rubens had a considerable tow on one of his laps early in the session which was the main contributor.

Pirelli used their medium compound tyre in Valencia for the first time. How did it perform?
The medium compound was still a good step slower than the softer option compound.

Pastor had two punctures over the weekend, the first during Friday practice and again in the race. Have you established the causes?
Not yet, we are still inspecting the parts.

Can you sum up the performances of Pastor and Rubens over the weekend?
Both our drivers performed well this weekend. We let Pastor down in qualifying with the fuel system problem, we then had a problem getting the car off the line at the start of the race. Pastor had a puncture during his first stint which forced him into an early pitstop and a change in strategy from a two to a three stop. When Pastor exited the pits, he was at the back of the field from where he had to fight for the remaining 56 laps.

The team's home race comes next. How do you expect the FW33 to perform at Silverstone, and how will the impending off-throttle diffuser ban affect the pecking order?
We have a new front wing and revised diffuser for Silverstone. We will test two diffusers on Friday with the new off-throttle ban coming into play, as well as testing various new over-run maps. We are going to Kemble to undertake some additional aero testing in preparation for our home event.