I don't know if any one else stumbled onto this, but I found out (rather by chance) that it is possible to skip through the screen after a race where the damage of the car is shown. 

When the results screen comes up with all times and scores you click on continue to go to the repair screen and click once more to go to the upgrade screen. But instead of clicking once to go to the repair screen, you should double click very fast. This sends me right through to the upgrade screen. It might not be much but it does save a couple of seconds. 

Only thing is that next time you want to repair that car, you have to wait for the status bar to go down, before you can click repair. 

I'm on iPhone 6, iOS8.1 and v3.0. Any one else found this?