[Donnchadh MacGarry]

I did a lot of practice Sunday evening at Imola as I had free time and wanted to get an idea of the tyres now that the wear is set to 100%, which will hopefully roughly apply to the other tracks. I did 17-18 laps (roughly 30 minutes) on soft, medium and hard tyres using a 50L load for each stint. Here is what I found:

• Soft:          Average time = 1:40.672,     Tyre wear was at yellow after 5 laps, and red after 15 laps.
  
• Medium:   Average time  = 1:41.178,    Tyre wear was at yellow after 8 laps and red after 15 laps.
  
• Hard:        Average time = 1:41.104,     Tyre wear never got to yellow, the app says they'll go 40 laps before turning yellow which seemed right from how my stint was going.
  

I also noted a pitstop with a tyre change altogether loses roughly 33 seconds, where the tyre change alone takes 10 seconds (and you can add up to 17L fuel in this time).
[Edit: I used to have 60 seconds written here instead of 33 seconds, as I got mixed up when reading the pitstop times from my practice laps. If you add 50L of fuel then the pitstop loses 60s. Apologies for that major blunder and to anyone who got misinformed by this before the edit.]

Since the 2019 season, with its 170% tyre wear that required hards for both stints, had races that went 35 laps where in one race the leader finished at 1:00:21, I do think 36 laps is certainly possible for the races this season (maybe 37 laps too, I'm bad at estimating the potential time improvement as I don't know what the fastest people can do compared to me). 

Looking at the data, assuming I had the correct settings on and that my driving was consistent enough to give reliable data, it seems to me that the medium tyres are a really bad choice for any strategy. They don't really last longer than the softs and very early in the stint were lapping slower than the hards. 

My understanding is that one pitstop is mandatory that involves either at least 1L of fuel to be added but tyres don't have to be changed, or any amount of fuel can be added with a tyre change. Please correct me if I'm wrong on that. Since the refueling rate is so slow as I mentioned in a previous post, I'm trying to minimise the fuel added in a pitstop (which is easier on 100% fuel usage compared to 200%) so I'm thinking these might be plausible strategies.
[Major Edit: I've renamed/renumbered the strategies and grouped them slightly differently before and have given them a better explanation.]
[Edit (again ffs): Pretty much all of what I wrote next was when I incorrectly thought the pitstop with a tyre change and adding up to 17L fuel took 60 seconds and not 33 seconds, so I wasn't considering a two stopper. Perhaps with that correct information then maybe a two stop strategy with softs used in all three stints might be a possibility, but I'm still leaning on saying no for Imola at least. I might have an update on that later this week.]


I have two main strategies that determine what you start the race on. Both of these strategies have two sub-options that you can choose between in the middle of the race depending on how it is going, which is really nice as it allows for some flexibility. 

1. Start on hard tyres with fuel to last the race, 93L for Imola is about 38 laps which allows some comfort room for fuel miscalculation. Pit at about 40:00-45:00, so lap 23-25 for Imola, and choose option either 1a or 1b below.
   
   a.  Don't change tyres and add 1L of fuel.
   This is the fastest possible pitstop you can make as you will be stationary for just under 1 second, which is good for gaining track position for a circuit that's hard to overtake on. You might be vulnerable in the second stint initially to someone who followed option 1b and switched to softs, but you will have a head start and if you can hold off their initial push then they should loose that extra grip before the last few laps of the race. Technically for this sub-option you can pit anytime in the 00:10 to 00:50 window as it shouldn't matter, but then you don't have the option to change your mind and switch to 1b if you pit very early. This option is also good if you got major damage that immediately needs repair from 00:10 to 00:35 as making the softs last in the second stint would lose too much time, although I would also put on fresh hards in this case as repairs will surely take over 10 seconds.
   
   b.  Switch to soft tyres and don't add fuel.
   The stationary period is 9 seconds longer than 1a, but you might be able to make up the lost time as you drive flat out on softs in the second stint. Nailing the lap to pit on is essential for this one. Too early and you'll be on very worn softs for the last few laps, which will lose a lot of time and you might make mistakes with the lower grip that lead to spins/crashes. Too late and you won't have maximised your time on the softs meaning you won't make up for the extra 9 seconds and the track position that you lost. Theoretically I calculated 1b to be quicker than 1a by roughly 3 seconds at Imola, but that is for a scenario where there is no other cars in the way. If there is a lot of traffic, you could lose a lot of time trying to make overtakes which could then make 1a quicker than 1b so you need to take that into account. Technically for this option you could start the race with 76L of fuel and add 17L in the pitstop, but if you do this then you are locked to this option and won't be able to change your mind and switch to option 1a mid-race, so I wouldn't recommend it.
   
   
   
2. Start with soft tyres and 17L less fuel required to last the race, so 76L for Imola to have the comfort room. Depending on how you feel with grip, lap times and track position, choose either option 2a or 2b below
   
   a. If you feel comfortable and aren't losing too much time, go until 30:00 and pit. Switch to soft tyres and add 17L of fuel.
   For Imola, this will involve driving the last three laps of each stint on tyres in the red zone of grip, so you need to be very careful on those laps. Being gentle on the tyres is essential for this sub-option and it is probably the most difficult one to drive. Theoretically, from my laptimes above, this is the fastest option out of the four by a few seconds, but that's for a hotstint scenario with no one on track. There can be other more important factors that make this strategy worse when facing opponents, like getting slowed down by opposition when the tyres are fresh and the increased chance of making mistakes when low on grip and under pressure from a driver behind. For tracks that have more tyre wear than Imola, I would expect this strategy to perform much worse as there will be more time spend on low grip tyres.
   
   b. If you don't feel comfortable at all as the car has lost too much grip and you have a while to go before the 30:00 mark, then pit at anytime after the 10:00 mark. Switch to hard tyres and add 17L of fuel.
   This is the reverse of strategy 1b. It is faster than 1b for the first 15 to 20 minutes of the race and slower than it for the last 15-20 minutes.
   

When comparing strategies 1 and 2, personally I think starting on strategy 1 is a really good choice, especially if you aren't as confident with the car. It allows you to take the start of the race a bit more safely, as losing places is not as critical since you will be running longer. What's more if you don't get overtaken in the early stages of the race then you will have a huge advantage in the latter part. It avoids the scenario of running of low grip tyres like in strategy 2b, so you will be less likely to make mistakes. It allows for the most flexibility on when you want to decide to make the mandatory pitstop. Finally it allows for the chance to use the quickest possible pitstop (1a) which is great when trying to undercut or overcut. These benefits are why drivers in a real life series like F1 will try and start the race on harder compound if they are able/allowed to (there are other rules that also influence the choice of starting tyre compound).

Strategy 2 will be much quicker than strategy 1 for the opening 15-20 minutes of the race due to starting on soft tyres rather than hards and also due to the smaller benefit of starting with a lighter fuel load. This will make it easier to make early overtakes if qualifying doesn't go well, or create an early lead for those starting from pole. However it is important to maximise this extra grip on the softs in this opening period. Getting held up in traffic on fresh softs early on will really take away any benefit from starting on them. Getting the good start will mean you need to be a bit more aggresive, which is really risky when cars are bunched up. Picking strategy 2 also means you are locked into making a pitstop that involves a tyre change, since one set of softs will definitely not last the race. You can't make an ultra fast pitstop like in strategy 1a to gain track poistion.



While I focused on Imola where I used Patrick's setup, I think there is a good chance that these strategies could apply to a lot of the other tracks and setups too, depending on how abusive they are to the tyres of course. The lap number of when to pit will change, but the time on the clock in the race shouldn't change by too much. Fuel should be recalculated for each track, especially if using a different aero setup. Another thing to note is that Imola has quite a large timeloss for a pitstop, due to the track's very long main straight. I seem to remember Sky's broadcast said it had the longest pitstop time loss out of all the tracks this season in F1. Perhaps a track that has less of a time loss in the pitstop could accommodate a 2 stopper with 3 sets of soft tyres? Let me know what you think of these strategies, if there was anything I overlooked or made a mistake on, and if there are any alternate strategies to mine that might also be good.