I have build 2 prototypes, 1º - new version of Heirloom with 12" wheels and 235-front 245-rear semi-slick tires and weighting around 1100kg, 2º - a small car with 10" wheels and 195-front/rear semi-slick tires and weighting around 650kg.
The 1º got 1.04g in 20m and 0,96g in 200m cornering, while the 2º got only 0,98g in 20m and 0,90g in 200m. Testing this difference on a equal car (same body and engine) got me around 6s in Mazda Raceway Laguna Seca.
I only thought about that because a bigger car can fit a bigger engine and bigger tires. But while we advance in time we probably will see this difference disappear, so we could just wait too.
Anyway, I’ll bring Heirloom to fight for podiums again, but this time with a V12 OHV engine.