Valve Overlap

[Steve]

>Bob-
>
>I remember watching the Zakspeed Capris blowing 3 feet of flame out the
pipe
>right before they hit the apex.  Same reason?
>
>-Mark
>
>
Most likely they were mechanically injected and there was no fuel cut when
the throttle was closed.  Porsche 935's used to do it all the time before
they were electronically controlled.  Also the fuel going through on the
overrun would cool the combustion chamber and would ignite at the tail pipe
exit where there was enough oxygen to burn.

The reason most current race cars don't do it is to conserve fuel.  That
means less used over a race distance so the car carry's less fuel and is
lighter.  Supposedly the Honda F1 V12 engines went back to adding fuel on
overrun for qualifying because Senna felt it gave better throttle response.

Steve