Kilcoo - thanks for the explanation.kilcoo316 wrote:CMSMJ1 wrote:This is what I do not understand. The inlet valves in an engine are downstream of an individual throttle body
How do the inlet valves neighbours have any bearing on this isolated little valve?
The butterfly in the body must correspond to the valve timing.
And the airbox stagnation pressure profiles over the throttle bodies will be affected by its exposure to the various throttle intake manifolds - as they are all at different pressures due to the firing sequence.
Therefore the flow into each intake manifold will be determined by the airbox pressure profile - and this flow forms pressure fluctations within the manifold - especially considering the rev range we are talking about.
This variable flow will affect the valve operation.
You could assume the valve is drawing from a constant pressure reservoir, but how accurate would that be? 98%, 99%?
Accurate enough for an F1 engine?
I still do not agree/understand..
Why does the butterfly in the throttle body have to correspond to the valve timing? The butterfly is open a set amount or it is not. It opens this much regardless of what the valves or valve timing is doing.
The throttle is opened. The debate about whether an intake charge is sucked or pushed into the inelt tract is in another thread but regardless the charge into the one tract is independant of another inlet valve.
The inital post was about R&D tools. It is agreed that a single cylinder bench for flow testing etc is a heavily utilised tool.
Your point about whether it is good enough for 99% accuracy etc is not the point we are making..
You could say that a badly designed V8 would give you less accurate results than a well designed single cylinder test rig.. SO what do you do then?
(I still want to know, without using Ronspeak
, about the airbox pressure waves as I think this is a non event that has very little bearing on the system.You can argue the nths of a percentile...and would be rightly pedantic to do so!
This could run and run eh?
