As it stands now you can only choose stage 1 turbo, stage 2, stage 3 etc. Sports tires soft medium or hard, etc etc. Not to great for giving cars individual identity . If manufacturers wont let PD give the game parts with different performance then just give us more variety of parts. Instead of just 4 stages of turbos being all identical give us a variety of turbos for each stage. One Stage 4 Turbo could boost you to 900 HP with medium turbo lag. Another Stage 4 turbo could get you to 1,300 HP but with massive lag. Maybe 3 levels for all 4 stages of Turbos Have positive and negative effects for tuning. Trying to get 1,300 HP out of your engine should require heavier engine parts and multiple intercoolers increasing the weight of the car and changing it's balance toward the end of the engine. Rims shouldn't just be for show and bling. Simulate the peformance and ride quality between a 15" rim and a 18" rim. Also give more control over the ECU or any computer upgrades. Let us tinker with fuel mixture ratios, boost levels etc. Dont give us exact HP numbers every time we add a part. Let us tinker with the timing, fuel mixture etc and find the perfect balance ourselves with a dyno etc.