Hi Brock,
GraemeSmith wrote:So to restate my original question: Have others observed poor response to rapid throttle opening on the aeroVee and RevMasters.
I have no recent experience with a slide carb so I can't answer your question.
BRS wrote:Since the fuel is added to the intake some 4' (apx intake tube length) from the heads it takes a bit of time to get from the carb to the cylinder, yet air flow increase is instantaneous when opening the throttle. I'm convinced (for now) that the engine leaned-out as I too quickly pushed in the throttle thus increasing the available air before the fuel had yet arrived to the cylinder. At least that is the assumption I'm going with.
Just some comments. Until recently I hadn't given much thought to exactly how the air and fuel get mixed during induction. I had envisioned a fine mist coming from the carb that instantly evaporated into the air and then headed for the cylinders.
Based on what I've been reading, with carburetors and throttle body fuel injection, much/most of the fuel ends up on the wall of the induction plenum (intake tubes). When the experts try to model a throttle body injection system they even have a name for the fuel deposit. They call it the Tau puddle. The fuel gets mixed with the air by evaporating the fuel off of the intake plenum wall. Under rapid acceleration the Tau puddle gets depleted resulting in a momentary lean condition. If the guys modeled the Tau puddle correctly, they will implement acceleration enrichment (accelerator pump) correctly, and the momentary lean condition will not be noticeable. Of course we don't have an accelerator pump so what you experienced could well be a momentary lean condition but I really don't know.
A question for you. Did your cylinder wraps reduce your CHTs? Inquiring minds want to know :-)
Wes