Single turbo e38 SD Camaro horrible boost oscillation w/ GFB 3

Hi all, Trying to finish my speed density tune and smooth everything out with my new turbo install. I have a 7675 single with a 44MM wastegate recirculating into the downpipe. Using a GFB 3 boost controller, with minimum duty cycle the boost is very stable, in the log posted below I have the duty cycle ramped up to 60%. The boost becomes extremely unstable and oscillates very bad. I'm aware of the 2x spring rate rule but starting with a base pressure of 5 pounds and having it oscillate from 6.5 all the way down to 4psi and back up to 6.5? seems like this could be something with the wastegate or solenoid or even the controller? The tune is a little rich, I've since leaned it out and smoothed the VE table. I should note the tune is on complete speed density with the upgraded OS from hptuners and the maf disabled. Not really sure what else to try at this point, I routed the wastegate lines a little different as per a forum I read with GFB's response and that had the turbo spool up very quickly hitting my boost cutoff with no control over it whatsoever. Thanks to anyone who can help.

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Originally Posted by nty1234

Hi all, Trying to finish my speed density tune and smooth everything out with my new turbo install. I have a 7675 single with a 44MM wastegate recirculating into the downpipe. Using a GFB 3 boost controller, with minimum duty cycle the boost is very stable, in the log posted below I have the duty cycle ramped up to 60%. The boost becomes extremely unstable and oscillates very bad. I'm aware of the 2x spring rate rule but starting with a base pressure of 5 pounds and having it oscillate from 6.5 all the way down to 4psi and back up to 6.5? seems like this could be something with the wastegate or solenoid or even the controller? The tune is a little rich, I've since leaned it out and smoothed the VE table. I should note the tune is on complete speed density with the upgraded OS from hptuners and the maf disabled. Not really sure what else to try at this point, I routed the wastegate lines a little different as per a forum I read with GFB's response and that had the turbo spool up very quickly hitting my boost cutoff with no control over it whatsoever. Thanks to anyone who can help.

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I looked for the manual for the GFB3 with no luck.
There is a PID type control running on it. So something isnt set right.
Can you try to ramp the boost in slower?

Not that I know of. Can't find anything within my tune with hptuners that will allow me to change the frequency of the mac valve that's connected to the gfb3. I may be wrong as I'm new to the turbo world but I believe that is only for standalone ecu's. If anything I can only make the boost ramp in faster, I have the gain setting set to 0 which would be the natural rise rate of the turbo. I've done my best to set a peak boost target with all that mess of it oscillating and even tried to use the closed loop correction (sensitivity setting) on it, but still no hope.

UPDATE: FIXED

Probably deserve some roast on this one but I completely forgot about the overboost feature on the controller and it was set at 5.4psi shutting off the solenoid when exceeding that limit.