Not too many years ago the Friday pit walk was an opportunity to get very close to the cars, mechanics and other team members. Slowly this intimacy is vanishing and the hoards of fans who descend on the pit lane mean there are now barrier ropes a meter or two in front of each pit, a (poorly policed) separate path for disabled access and a huge scrum 10 or more deep around any pit with anything slightly interesting. Unsurprisingly some teams have also taken to selling merchandise at sometimes inflated prices! Nevertheless with perseverance and good humour there are chances to see things that are not visible from the grandstands.
Paintwork. The sponsors logos are mostly stickers now, look close to see how thick stickers are or how they are faired in. Sharp, thick edges create drag and slow it down.
Smart thinking. At the Audi pit a few years ago they had a stack of flat aluminium plates with a 45degree angle each end. When they had a pit stop practice they used these to put spare tyres on during pit stops so they don't roll away. That year Peugeot lost time by tyres rolling away at pitstops. Less time in the pits is good.
Deception. In 2009 Audi had wraps on their rear spoilers. Rumour was that Peugeot were requesting disqualification until they thrashed the R15s anyway.
Pit organisation. May not be set up for the race (on Friday) but things like the spare parts, how easily available are they? If your car blows a front tyre you want front body work, suspension and floor to hand and not in the truck.
Team Karma. If there is mad panic in the pits on Friday then it doesn't look good. More haste less speed. A panicking mechanic could easily break something when a cool head is best.
Speak to the “guards” at the rope of each garage. CA member experience: “We asked each of them what their role was in the team - we spoke to Chamberlain's Tyre man, someone who did transport, and at the last, we got the Bentley Project Director, with whom we had quite an interesting chat, given that neither of us were particularly clued up on anything”. Would be interesting to know where the Red Bull, Mazda and Toyota folk are spending their time!
Bodywork. Panel fit on cars. Aero is very important, the panel fit on cars is something to look for. Big gaps and panels not flush looks bad as air will leak out and slow car down. Also means car build and set up has not been done to high standard. For example there was one car which had panel fixings which pushed the floor down and meant the front bodywork did not sit flush with sidepods meaning you have disturbed airflow, the floor was not flat either having a bulge from the fixing pushing down. Minor points but they all add up to lost top speed and downforce.
Dodgy repairs. When the bodywork is laid out at the front look for repairs done. If it has a really bad wet layup repair on it then it carries extra weight. If there are riveted repairs then it is not as strong so could flex under load. Also see if on any repairs there are multiple layers of paint, this adds weight and could affect fit of panels.
Spares. Teams usually have all their bodywork in the pits on Friday and should be fitting them to check they are interchangeable. Bad news to find in the race you replace some bodywork only to find the fitting is wrong. Should all fit the same otherwise we are back to the drag and slower car again.
Engineering design. Harder to spot: Does the car have fuel pumps and filters easily accessible so they can be replaced in seconds not minutes? Ditto batteries. Hand throttles: Know a good story of one team who didn't have a hand throttle because they thought the engine management would keep the engine ticking over to get back to the pits. It didn't and they lost a lot of time.
Practice. Always good to see them practice. They are only allowed one air gun so they need practice to make sure the car is in the pits for the shortest length of time. Also drivers help each other into the car. They have to change seats and adjust and tighten belts so they need to practice as well.
Freebies. Less likely each year.