Boosted - Rubber tire shells are desigend to have more over all down force and more steering than foam tire carpet shells.
Foam tires have more inherit grip and steering. To make the cars fast on carpet special body shells are used to help free the cars up. If you ran a rubber body shell on foam tires the car would be very stuck and slow.
Foam tire bodies:
Protoform DNA (Original version)
Protoform Pontiac G6
Carpet bodies are easy to spot as they lack the splitter lip located on the front lower edge of rubber tire bodies. This splitter increases front steering and traction.
Foam bodies usually also have lower rounder tops to their trunk areas. This spills air from the back and reduces traction.
Running a foam tire body on rubber tires will make any car push, slide and feel skaty. Switch to either of the Protoform Mazdas and the car will feel better right away.
What I run: Schumacher Mi5/Associated RC10R5.1/Associated RC12R5.2/Futaba/HobbyWing/Team EA Motorsports/BSR Racing
Where I run: Florida Indoor R/C Complex/Thunder Racing/Florida On Road State Series