R33 Pfc Boost Controller Issues

[Cubes]

'Apparently' the 3bar map sensor is required if running over 17psi?

This was over at the rx7 forums so not sure how accurate it is.

Paul?

[paulr33]

yeah joel could be onto something

the manual mentions a bit about "issues" control over 1.3kgcm2

but its not clear. does the map sensor let you see to 1.6bar ?

[dangerman4]

yeah joel could be onto something

the manual mentions a bit about "issues" control over 1.3kgcm2

but its not clear. does the map sensor let you see to 1.6bar ?

not sure we didnt go past 1.35kgcm2 as it the boost wave got real ugly

[cameron]

I've recoreded and controlled over 2bar with the avc-r which uses the same solonoid and map sensor? On a external gate with 17psi spring

Altho with the avc-r the duty cycle is adjustable via rpm. looks like it getting boost spike and its cutting it, try the lower duty cycle

[saliya]

im running a 18 pound actuator and a brand new PFC boost control kit.

attached is a dyno print out showing the wave.

i have installed a 2mm restrictor in the feed line to the solenoid and the results are on the printout.

before i installed the restrictor it was even worse.

the boost settings are on 1.6 kgm cm

and the duty cycle is on 83 %

its a built rb25det with the new gt3540-iw

if i go any higher with the boost the wave gets bigger, and longer.

does any one have any other solution?

cheers Darren

Hey Darren,

Is your solenoid inline between the pressure source and the gate, or is it operating as a bleed?

Have you tried it the 'other way'?

Does the PFC "learn" over time? If not, what does that last number displayed on the HC mean?

Regards,

Saliya

[dangerman4]

Hey Darren,

Is your solenoid inline between the pressure source and the gate, or is it operating as a bleed?

Have you tried it the 'other way'?

Does the PFC "learn" over time? If not, what does that last number displayed on the HC mean?

Regards,

Saliya

yes its in line.

no idea!

[Sydneykid]

Sorry Gary you have lost me.

i have a bad headache.

what ebc are you talking about?

where do you recomend running the lines from for the ebc?

should i get a fitting put into the outlet of the comp cover?

or what?

also should i plug the map sensor into the bov instead?

cheers

You posted this;

the map sensor i joined with a T fitting into the line to the EBC from the plenum

I assumed;

"map sensor" = the PFC BCK map sensor

"EBC" = some other (no longer used) EBC

If you have lots of vacuum tubing (and T pieces) between the plenum and the PFC BCK map sensor, you will get slow response to boost changes. Lots of air in there buffers the pressure changes, especially when you have a turbo that ramps up onto boost rediculously fast.

So make the vacuum hose from the plenum to the BCK map sensor short and get rid of (or move) anything else on the same vacuum feed.

Looking at the two boost curves (gizmo and BCK) I see the same waves. The gizmo looks better only because the scaling is smaller. Same problem then as you have now. It's an auto, so how are you locking up the torque converter? If you aren't locking up the torque converter, than that is the problem. Simplistically, when the turbo hits boost the torque converter unlocks, this releases the load from the engine and it produces less exhaust. Less exhaust means less boost, less boost means the torque converter locks up again, etc etc.

When dynoing an auto, we always log the engine rpm, that way we can see the torque converter effects.

cheers

[GunMetalR33]

what do you mean learning value?

The learning value is the 255 initial value that you cannot change. If you get the duty cycle close enough the PFC uses (fuzzy logic) to fine tune it. The learning value will change as the computer fine tunes it self. Therefore if this value does not change, you either have the duty perfect OR you are no where near. In your case I reakon you probably have too much duty.

What is your duty set at?

PS, the above is just my opion. Might not be fact but seems to work for me...