Is there any point upgrading cars on the 360?

Hi all, apologies if there is a similar thread, I have checked but couldn’t find any.

I was just wondering if there was any point upgrading your cars on the 360 version of the game? If the opponents cars will automatically scale up/down so they have a similar PI to you, why would you spend credits on performance upgrades if they do not make you more competitive?

Sorry if I have missed the point, this is the first Forza game I have owned.

Thanks

For online racing. You’re not going to be competitive if you don’t upgrade. But for single player, there’s really not a need to unless you want your car to handle a little better.

So for the purpose of single player you would suggest only really concentrating on handling upgrades then?

Thanks