Quote:

my motor have 2.25 / 1.55 valves maybe it has something to do with it..



On your PS motor, what is the LSA and installed at.
The fact that you run a small valve on the exhaust
is why it has so much duration. Like was said already
it force over time to measure power.... every pulse
(firing)in a minute is what is measured.... put more
pulses in that minute it will be more(if you can get the
air/fuel in and out). Now when you get high rpm you
have to REALLY control the valves... bounce off the
seat will kill the power(letting that pressure out
with only a very short period of time to play in)