I've grown a little frustrated trying to grind for customization parts yesterday, but then I switched from a fully upgraded Mitsubishi Motors Eclipse to an almost stock Dodge SRT4 which made me win the Optional Races more often.

I also read somewhere that the Cars the opponents drive depend on what your Car is at the moment. Not just the Class, but also the Upgrades being based off of what Upgrades your Car has. So far, I've only really upgraded Nitrous, Brakes & Tires with no other Performance Upgrades.

I'd like to know more about this. Does this affect the Story Races, too? If true, does this mean I can just bring in a slower, less upgraded Car in the later Races and still be able to win without having to Upgrade a ton?

I've felt a little confused by the way the game decides Opponents based off of all the Car Details, and where it affects the Races. Can anyone tell me more about this? I'd mainly like to know how to make Grinding easier.

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