hey guys...

sorry for the silly question...but fd racer and I were out tuning my cars afrs on the datalogit and are ready to start upping the boost...can someone please explain how the duty percentages work on the boost controls on the pfc? there are two settings...one is for the boost bar level..the second is for the duty cycle percentage...one setting for each turbo...

how exactly do these percentages work??...

any input is appreciated...I have my own ideas but i want to be sure i am right before i attempt to up the boost to 16lbs.

thanks guys

j

 

come on guys...surely one of you knows the answer to the question.



share the wealth!

j

 

The first number tells the PFC what level your aiming for, the duty cycle % is telling it how often to cycle the wastegate open and closed to achieve the desired level. A very low duty cycle number will stifle boost, in that if you have it set for .85 and .80, but duty cycle numbers are low, say 46 and 48, then it would take longer to .85 psi and also might not make it to .85 due to the wastegate spending a good deal of time opened. If your close to making the boost level you want but ned to make a little more boost, just leave the .85 and .8 numbers alone and raise the duty cycle numbers a few points and it should make a little more boost than the .85.

Tim.

 

well said mr benton..cheers to the fantastic answer.

understood.


j

 

It also isn't a fixed thing. Interally it tries to learn and adapt. That is why they call it "base" duty. No one has said for sure how the learning works. From watching it a lot I think the learning isn't long-term. I think it just tries to adjust duty to match the target boost levels, but can only do relativeley small adjustments.