whats the pressure of piston in suction stroke....and if we increase it could we get more benifit
If you mean the vacuum value, then this should be around 20 inches and it's harmful actually and is referred to as pumping losses
nevertheless, there are some auxiliary components that utilize some of this vacuum, but this vacuum could be generated with an external device (e.g pump) therefor eliminating the harmful effects.
the vacuum inside the engine results from the restricted air flow by the butterfly that is partially closed
In a turbocharged/ supercharged engine there will be a constant pressure through the manifold which eliminates the vacuum from it altogether, also note that diesel engines don't experience vacuum at all
However, what "technology" excatly do you refer to and why should it be changed ?
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