Power Fc / R33 Help

[Duy]

Hi people, just need some input. Have been tuning my pfc for the last coulpe of days, have a RB25DET with GT2530 running at 1bar with std AFM and Injectors, seems that the max load scale has dropped from 15 down to 17 one the same boost? as I have been advancing the time in stages, watching for knock. I was under the impression that the load is relative to boost? 0 is load cell 9 on my setup and 15 was 14.7psi. I feel the engine is making more power with the time that I have tuned in which has a higher air flow which has brought it to load cell 17 but how can there be more load with the same boost?

Second Q's, I have been playing with the total advance timming to full load at say 4000rpm on 1bar, My timming is 14deg at that point, I have tired 15deg which it will knock at 88, having looked at some base maps of a RB25DET at the same points the std ecu runs like 21deg? Fuel ratio is spot on for all points (11.7 on 1bar all the way to red) I have a FMIC (PWR), any help is greatly apprreciated.

[paulr33]

the load axis is based on what the airflow says, its nothing to do with pressure but amount of air coming into the system. if you force in more air, it will drop lower on the load axis

[Duy]

How have I forced in more air? the amount of air flow through the AFM to the turbo intake is relative to boost is it not? how can you have more air entering the system then what it is pushing out?

[paulr33]

if you increase boost pressure, as long as you are in effiency zone of the compressor wheel (the compressor map will tell the effiency zone) then it will bring more air into the system. so by adding more boost, it forces in more air. this in turn is shown via the airflow meter signal.

there is always more air coming into the sytem, despite pressure being fixed.

this is usually why map sensor setups are sucky with load points, as one boost hits target they dont show any more into coming into the system, even though more is coming in, but pressure is the same