More Boost at half throttle? G70 2.0T

[G70n 2.0T Sport w/Brembo]

I hope someone can explain this issue I have been having, it seems I'm feeling more boost when I let off the throttle then I do at full throttle. It has a K&N filter and a cheap plugin chip. side note, has anyone installed a JB4 controller on a 2.0T and what are the boost gains. BTW this is a manual transmission G70 Thanks in advance.

 

[Volfy]

Sounds about right. You can get an inexpensive OBD2 dongle and use a smartphone app like Torque to display Boost pressure and see LIVE readings for yourself.

Quite common to reduce boost pressure at higher RPMs, where the combustion chamber is more likely to see higher Peak Cylinder Pressure.

These are JB4 maps for Stinger/G70:

Map guide as of v5 firmware (selected via JB4 Mobile/laptop interface. Map1 is the default map)

Map 0: JB4 disabled
Map 1: 4psi over stock peak tapering to 2.5psi at high RPM. Default performance map suitable for all 91+ octane fuels.
Map 2: 5psi over stock tapering to 4psi at high RPM. Suggested for 93+ octane fuel.
Map 3: 6psi stock tapering to 5psi at high RPM. Suggested for high quality fuel including unleaded race gas, ethanol mixtures up to 30%, or high quality octane booster like Torco or Boostane.
Map 4: Valet map, runs around half as much boost as stock.
Map 5: Up to 7psi over stock. For use with unleaded race fuel and/or E85 mixtures up to 30%.
Map 6: User adjustable map. Enter value of boost over stock by RPM on user adjustment page.
Map 7: Up to 7psi over stock but without top end taper. For unleaded race fuel use and bolt on modifications. May not be suitable for E85 mixtures due to high fuel pressure dropping. If using this map on E85 you should be experienced at reading your own logs and evaluating ignition advance and fuel pressure.
Map 8: Progressive WMI (water/meth) map. Increases boost as a function of methanol flow & methanol boost additive. Holds boost low until WMI is flowing to avoid tip-in knock, and reduces boost as a function of WMI flow in the event of interruption like running out of fluid, leak, or component failure.

Source: JB4 Map Guide as of v5 Firmware