WI quantity calculations

[hotrod]

The engine bogging down shows up mostly as a subjective evaluation by the driver. In its usual usage the engine might stumble or hesitate a moment or just have a brief period where power seems to be down a bit. In severe cases bogging is very obvious, its like the cars ignition was turned off for a fraction of a second, or the car acts like it suddenly got much heavier and the engine had to work much harder than normal for a second or so.

An ideal engine, properly tuned, has good throttle response and seems eager to pull. When you blip the throttle for a down shift for example, the engine has a very sharp crisp response. It revs immedialtly and willingly. Under hard acceleration you get the feeling the engine "wants to rev -- it wants to pull".

On an engine that has a bad tune ( could be too much water injection or other things like improper timing etc.) the engine is not as crisp, there is a small but detectable lag between when you change the throttle setting and when the engine responds. It simply feels a bit flat. On an engine that you can hear the intake sounds it sometimes sounds like its strangling or choking on the excess water. A lot of tuners will say the engine sounds "soggy" it feels and sounds water logged.

In severe cases there may be an obvious loss in power when the WI first engages as the excess water actually reduces power output, then as the engine revs it gets the power back plus a small improvement at the top end. This might indicate a turn on poiint that is too early or the jet is too big until the engine gets higher up the power curve.

All very subjective, but one of those things you'll usually recognize when you see it.

Its like the driver who comes in for service and tells the service manager the car runs fine but just doesn't feel right, its a bit sluggish etc.
On examination the shop might find something like bad plugs. The symptoms were noticable to someone familiar with the car but a total stranger might think the car was running normally.

Larry