head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is execution, and it is a single point.

Execution · Twitch Chaos
Kart racing where driving skill fights a steady drizzle of random gag items.

Execution · Pure Mechanics
Open-world racer where banking risky speedpoints against human cops drives the tension.
Looney Tunes: Space Race leans Execution (Twitch Chaos); Need for Speed: Rivals leans Execution (Pure Mechanics).
Need for Speed: Rivals leans a little harder on execution, though the gap is small.
Looney Tunes: Space Race
Racing lines and drift control still decide most finishes
Need for Speed: Rivals
Open-road control with pursuit tech timing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Looney Tunes: Space Race
Light gag-timing duels against human racers
Need for Speed: Rivals
AllDrive mixes human cops and racers in
Looney Tunes: Space Race leans a little harder on variance, though the gap is small.
Looney Tunes: Space Race
Random gag pickups scramble race outcomes
Need for Speed: Rivals
Dynamic open-world encounters and weather
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Looney Tunes: Space Race
Shortcut and track knowledge compound every lap
Need for Speed: Rivals
Risk-versus-bank speedpoint economy
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.