CVCC is a system used by honda to reduce emissions by stratifying the combustion charge. In the City Turbo the throttle body appears much like a carb. A separate set of intake runners provides fuel to each of the CVCC valves located with a combustion prechamber. A rich mixture of fuel and air are added to the combustion prechamber which houses the spark plug. This is ignited and creates a flame front out of the prechamber.
Detonation occurs when two flame fronts collide in a standard combustion chamber.
One is caused by the spark plug, the other is caused by the high pressures, friction and shockwaves on the other side of the cylinder igniting an easily combustible mixture. Stratified combustion such as the CVCC system makes the second front less likely to occur as the lean mixtures in the main combustion chambers are hard to ignite. Performance of Honda City Turbos is really up to the individual owners. The braking system is very capable for such a small car. The front brakes are the vented disks and callipers straight off the 1984 Prelude, rear brakes are stock City items.