Any links to GAS Car & Track lists? I only saw the DLC/Car & Track wishlist thread.
I've actually got the game running right now, so here are the circuits:
Brands Hatch, Istanbul, Spa, Hockenheim, Yas Marina, Sepang, Mount Panorama, Algarve, COTA, Mont-Tremblant, Red Bull Ring, Indianapolis and Jarama. There are also fictional circuits - the Autosport Speedway and Okutama - and city-based circuits in Barcelona, Chicago, Paris, Washington DC, Dubai and San Francisco. There are also several drift circuits. All circuits have multiple configurations.
As for the cars:
TOURING - (BTCC) Chevrolet Cruze, BMW 320i, Ford Focus, Honda Civic; (EuroV8) Mercedes C63 AMG, Audi RS5; (Stock Car Brasil) Peugeot 408, ADC Presteza-14 (fictional); (V8s) Falcon and Commodore utes and sedans.
ENDURANCE - (GT3) Mercedes SLS AMG, McLaren MP4-12C, Audi R8 LMS, Aston Martin Zagato; (SuperGT) Honda HSV, Nissan GT-R; (LMP-2) Lola B12/80.
OPEN-WHEEL - (Formula 3) Dallara F312; (A1GP) Lola B05/52; (IndyCar) Dallara DW12.
STREET - (Hot Hatch) Ford Focus, VW Golf R, Mini John Cooper Works; (Coupe) BMW 1 Series M, Subaru BRZ, Honda Integra; (Performance) BMW M3, Mercedes C63 AMG, Audi RS5; (GT) Mercedes SL65 AMG Black, Jaguar XKR-S, Alfa Romeo 8C, Aston Martin Vanquish; (Supercar) SRT Viper GTS, Aston Martin One-77, McLaren 12C, Pagani Huayra, Mazda Furai, Mercedes SLS AMG Coupe Black; (Hypercar) Bugatti Veyron, Koenigsegg Agera R, Pagani Zonda Revolucion, McLaren P1.
TUNER - (Muscle) Chevrolet Camaro SS, Ford Mustang Boss 302, Dodge Challenger SRT8; (JDM) Mazda RX-7 Type RZ, Honda S2000, Nissan Silvia Spec-R Aero; (Super Modified) Honda 5zigen Civic, Mazda Panspeed RX-7, Subaru Tomei Cusco Impreza WRX. This category also contains several cars tuned fir drifting.
Each discipline also has multiple one-make championships, which I have not included because you only race them occasionally in career mode.