Solved

Which area is the most important in design?

Which area is the most important in design? Fuel economy or tyre economy? Which has the greatest impact on the race?

Neither!!! 

In fact they are near the bottom as far as priority goes. 

Acceleration, Braking, Handling, Downforce. And then Tyre economy and Fuel

FE & TE do play a part towards the end of the season as they become the the 2nd last pair of car attributes  to be maxed before Reliability and Durability. 

There are various way to deal with FE & TE without assigning any DP to it. 

• One could take an extra stint to use speed as leverage/advantage thereby carrying less fuel. 


• Utilize suppliers as a supplement.


• or a combination of the above.

Good question Gunther!!

It may sound rather obvious to some of us, but most of us come into this game thinking real racing logic applies. It doesn't always, simply bc it's a game. 

Thank you very much for your answers but it was not what I expected, sure I was not very clear.

I know that Acceleration, Braking, Handling and Downforce are priorities, my intention is to know after that, which area is more important, if it is more important Fuel economy or tire economy.

Imo, it always depends on the next track and ur strat. If u use soft tyres all the way and they never get below 50%, u don't need to improve TE. 

On the other hand, if ur stints are well planned and u know, u r going to have 0.0 to 0.3 liters left, no need to improve FE. Improving FE here might even be a bad thing: u r going to have more left, like 0.2 to 0.5 liters.

Improving FE is useful, if it leads to putting a liter less at start and pit. Of course u only know for sure, if u do very detailed calculation. 

If improving TE is helpful might be easier to answer. U should know pretty well, to which point u r going to drain ur tyres. But improvement effects are small!

35-40% is my threshold.  Monaco being the exception.
So, I'm down to the last 6 races of the season, maxed 6 Design areas, and here's why I tend not  to worry about TE and FE; bc I haven't pinned down the exact intervals/improvements on those 2.  I bank on making it to the races and making adjustments if needed on the fly.  

I’ll keep it short & simple: fuel economy.

In my opinion, fuel economy is more important than tyre economy. It is always good to have less fuel than others because it means you can go longer and still have the same pace. But you would have to upgrade tyre economy to have the full benefit. Make sure to upgrade both as fast as possible after maxing out the big 4

lol... so fuel is or is not ahead of TE in priority?

Ahead but still have to upgrade both?

in my opinion, Fuel is more important than tires.