[tholyoak]

Callaway increased fuel in a few ways

1) Larger injectors which required increasing the spring tension on the AFM so that the car wasn't running really rich when not on boost

2) Fifth injector in custom manifold just ahead of the TB. Its opperation controlled by a separate 'computer' which measured boost and engine speed and cycled the injector accordingly

3) 1lb boost switch, at 1psi of boost the TPS was grounded to trick the DME into providing full throttle enricment under boost.

Today I'm sure there are more elegant ways to do it by replacing the fuel injection system with a Motec or similar, but this allowed you to retain the Bosch system.

Todd