Regarding PowerFC boost control kit...

[Nexus_SiX]

Hi,

Can anyone help?

I am after an "idiots guide" to these following numbers. I know its for changing the boost but it will allow you to change both?!

I appear to have put my manual "somewhere safe" and can't find it.

Thanks in advance...

G.

[Steve]

The second numbers you have highlighted is the Duty Cycle. This is basically the amount of time the solenoid stays open (bleeds) in realation to the amount of time it is shut and allows boost pressure to the wastegate. It is expressed as a percentage.

The minimum you can set (from memory) is 10%, which would be sending boost pressure to the solenoid 90% of the time, bleeding 10% of the time - it would be used for low boost pressure.

The maximum you can set is 90%, which has boost pressure going to the wastegate 10% of the time and bleeding 90% of the time.

If the boost is spiking (I would put money on it in your case, those duty cycles seem very, very high for those boost pressures), you need to adjust the duty cycle down.

If the boost is lazy, or it isnt reaching full boost, you will need to adjust the duty cycle up.

If you change your boost pressure up, adjust the duty cycle up at the same time, if down, adjust the duty cycle down. The power fc has a self learning mode, which will optimise the solenoid actuation for optimum boost control BUT, if you are miles out of the ball park, it wont have a chance. For example, if I adjust my boost pressure up by .2KG, I usually adjust my duty cycle up 4%. then just monitor on the peak hold, if it is spiking (more than .1kg) I will adjust the duty cycle down by 2%. If it isnt getting to boost, I adjust duty cycle up by 2% at a time, until it is just spinking a little (less than .1kg) - from there I let the power fc learn for itself.

If you ever need a copy of the english manual (although its for an RX-7) one is available on line at he apexi usa website, look under electronics, then documentation or someting like that.

[Nexus_SiX]

Thanks for that!

I do get a bit of overboosting and thats prolly why!

[Sydneykid]

HiSteve, what's the 255 mean?

[S15200sxbroda]

255 - prob the gear judge hasnt been set...

[Nexus_SiX]

the gear judge?

The 255 number cannot be changed in this window.

Is there another part somewhere?

[Steve]

255, I have always wondered that myself.... might have to ask the signal guys when they come over to do a bit of tuning in May:)

[Steve]

After having a read, I am guessing that it may be the boost cut setting, ie, 0.25kg above the set boost level? Probably another thing that can only be changed by excel software.

[GunMetalR33]

I think steve is right because I was told by greenline in japan that the pfc cuts ignition when boosting .25kg over the set limit.

[rs73]

Is it also true that running boost above 1 or 1.2 bar using 3rd party boost controller and PowerFC will cause your engine check light on the dash to light on, because PowerFC could not monitor the boost anymore? The only remedy is using the dedicated Apexi boost control option that connects straight to the PowerFC, is this true or not?

[Micko]

The 255 value is the 'learning value' isnt it?

Not quite sure what it corresponds to so I think it is more of an arbitrary value than anything else. I can tell when mine is learning cos you can see this value changing & then it stays put once it has learnt.