Column one: switch setting, column two is starting vane pos, column 3 is boost.

0   LOW      LOW 
1   LOW      MED
2   LOW      HIGH
3   LOW      V HIGH

4   MED      LOW
5   MED      MED
6   MED      HIGH
7   MED      V HIGH

8   HIGH      LOW
9   HIGH      MED
A   HIGH      HIGH
B   HIGH      V HIGH




For 2017, we've revised the firmware slightly.


The 4 bands determine the initial vane position and the vanes are moved to this position as soon as the throttle is opened or the boost rises above the idle value. So with band 4, there will be a faster boost build up and from a lower rpm than with band 1.

The vanes then remain in this position until the max boost for that setting is approached. For a 2.5bar sensor, this will be at around 1bar, 1.2 bar, 1.4bar and 1.6bar respectively with the settings within each band chosing which.

The tps input reduces the max boost, overriding the setting on part throttle and on zero throttle, releases the vacuum almost completely.

With a 3bar sensor, the 4 boost settings will be approximately 1.2, 1.5, 1.8, 2.1 bar. The actual pressure will vary from the above figures so you may need to choose a lower setting than indicated.

On part throttle the boost will vary with load in the same it does with a wastegate turbo but the DGBS will not attempt to achieve max boost.



We designed the DGBS in response to requests from owners who have fitted a vnt turbo to their engine and have not been able to control the pressure effectively using a pressure actuator or the original

wastegate actuator.


It is not commercially viable to design a unit from scratch for such a small market so we use our Synergy 2 with hardware mods and extensions to drive the boost control solenoid and new firmware.


A turbo is an organic device relying entirely on waste exhaust energy so you cannot make it produce a specific pressure if there is not the energy to spin it fast enough, and nor can you use a rpm input to specify a particular boost pressure.  In any case, what does it matter if the pressure is not exactly what you want either on part throttle or full throttle so long as it is controlled and adjustable close to what you want?



MAP SENSOR. As we are aiming to control the pressure, the map sensor is the primary control input and is used primarily to control the maximum pressure.


TPS. The throttle position sensor (tps) input does enable intermediate boost pressure to be used on part throttle and also reduces the boost requirement to a low level with no or little throttle to prevent exhaust back pressures rising at low rpm & on the overrun. We recommend you use this feature if aiming for a large increase.


FUEL PRESSURE. On a common rail engine we also use the fuel rail pressure signal. The rail pressure is varied by the engine ecu depending on engine load, throttle position and rpm, so you can think of this sensor signal already including both the rpm and tps signals, making a very useful control input. Hence at idle or on the overr un, the vane angle can be backed off to reduce exhaust back pressure and/ or the boost pressure allowed to increase only when max fuel pressure is reached. We can also offer tuning option using 4 of our Synergy 1 tuning box maps to increase the fuelling.  This option also enhances remaps, which are often less impressive at low rpm (below 2000rpm) and so can reduce any turbo lag due to under fuelling.


MAF SENSOR. This is also useful primarily at low (off boost) rpm to back off the vanes and reduce the boost pressure on light load - at idle and on the overrun.


DASH OR INJECTION PUMP SWITCH. The tps input can be connected to a 2 or 3 position dash switch for manual control of low/med/hi boost, or a microswitch could be fitted to the throttle lever or  quadrant on a mechanical pump to give, for example, more boost on full throttle.


We are not claiming our unit will prove to be the ultimate solution for every situation - this is impossible without actually adjusting the unit or even modifying the firmware on the road or dyno. However feedback has been 100% positive and no unit has needed a firmware revision. Several customers have bought a second one for friends or customers.



  • Will it control a Holset turbo? We will shortly be releasing a version for the Holset electronic actuator eg HE351ve.
  • Will it work with a Hella actuator? Yes a version for popular Hella electronic actuators will be available this spring.
  • Does it have an rpm input? No, load or driver demand sensing is more useful which can be achieved by the tps.
  • Does it control the vanes progressively? Yes, the vane angle does not simply switch from one extreme to the other and is varied in relation to the boost pressure and the signals from the fuel pressure/maf sensor &/or tps/dash switch.
  • Can I choose a specific boost pressure? Yes, but the exact pressure will depend on the turbo spec & fuelling as well as the setting - normally this covers the range 18-25psi. Let us know if you have a specific requirement.
  • Can I choose the low rpm boost? Yes, there are 16 settings in 4 bands, each band varies the starting pressure (low rpm vane position) and each setting with a band alters the high rpm vane angle giving a very wide range of control.
  • Does it have a throttle signal input? Yes it now does, but this does not directly control the pressure, it overrides the maximum to reduce it to an intermediate level, or very low leve with no throttle.
  • Are the results guaranteed. Since a major mod such as changing the turbo is a one-off mod, there is no way to guarantee a particular result without access to the vehicle. Instead we provide plenty of adjustments and the options of the tps or fuel pressure signal gives additional control mechanisms. We are happy to modify the firmware at minimal cost if necessary.

A typical boost control solenoid (aka electric valve, or pressure converter)


The VW N75 version looks similar but has a different connector and the air filter is not fitted, instead there is a 3rd tube which ideally needs a supply of filtered air as it is the vacuum release for when the valve is switched off.



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 UPDATED 01-01-2020

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