The R35 has one wastegate actuator on each turbo. Turbosmart's 7 psi IWG75 is a direct replacement for the factory actuator. Its stiffer springs need tuning, and HKS says its actuator upgrade needs fuel re-setting. We supply parts; your tuner sets the boost.
What an uprated actuator changes
Turbosmart says its IWG75 has a higher working ratio than the factory actuator, from a larger effective diaphragm area and revised springs. With the same base pressure as the factory actuator, Turbosmart says to expect a broader boost and torque curve, with peak boost reached earlier in the rev range and held for longer. Higher base pressures add to this, and Turbosmart says tuning and recalibration is then likely required.
Turbosmart IWG75 for the R35
| Spring | Part number | Tune needed? |
|---|---|---|
| 7 psi (0.50 bar) | TS-0615-2072 | No, a direct replacement for the factory actuator |
| 19 psi (1.31 bar) | TS-0615-2192 | Yes, ECU tuning or calibration |
| 24 psi (1.65 bar) | TS-0615-2242 | Yes, ECU tuning or calibration |
Turbosmart lists a silicone Nomex diaphragm, a billet aluminium body, stainless steel rods and clevis, and a locking collar.
IWG75 7 psi | IWG75 19 psi | IWG75 24 psi
Turbosmart IWG75 Twin Port
The Twin Port adds a second pressure port to a separate chamber. Turbosmart says the pressure in that chamber works against the spring, which gives a greater range between maximum and minimum boost than a single port actuator. The R35 kit is a direct fit replacement and includes two actuators, one for each turbo, with a bracket and rod. Ask your tuner how the second port will be controlled.
HKS actuator upgrade
HKS fitted these strengthened actuators to its GT570 and GT600 R35 turbo kits, and now sells them on their own for a light boost increase or a repair. There is one for each side. HKS gives a set pressure of 88.3 to 93.2 kPa (0.9 to 0.95 kgf/cm²) and says fuel re-setting is required, so plan a remap.
HKS actuator upgrade 14030-AN001
Rattle or boost drop: check first
A rattle can come from more than one place, and new actuators replace only the actuators, not the wastegate flap inside the turbo. Have the noise diagnosed by a specialist before you buy. If boost falls away, ask your tuner to log it first.
Fitting and setting up
Turbosmart's IWG75 instructions say to consult a specialist before setting boost, to set boost on a dyno and not on public roads, to fit a boost gauge permanently, and to check the air/fuel ratio while setting boost, because more boost can make the engine run lean. Have your specialist fit the actuators and set them up with your tune.
Ordering
The Turbosmart actuators show their price on each part page. The HKS actuator is price on application, made to order and shipped from Japan. Imported parts usually take 1 to 2 weeks at the minimum, and UK delivery is quoted before you pay. Email us or use the contact form with your car's details.
Delivery and returns | R35 turbo parts | Turbosmart | HKS
Related guides
RB26 boost control | R35 GT-R stage 1, 2 and 3 | R35 GT-R common problems
FAQ
Do I need upgraded wastegate actuators on my R35?
Not always, so ask your tuner whether the factory actuators are limiting your build. Turbosmart says its IWG75, at the factory base pressure, gives a broader boost and torque curve from its larger effective diaphragm area and revised springs. The 7 psi version is a direct replacement; stiffer springs and the HKS upgrade need a tune.
Will new actuators fix R35 wastegate rattle?
Not on their own. A rattle can come from more than one place, and new actuators replace only the actuators, not the wastegate flap inside the turbo. Have the noise diagnosed by a specialist before you buy, so you know which part is at fault and whether actuators are part of the fix.
Does the Turbosmart IWG75 need a remap on an R35?
The 7 psi version doesn't. Turbosmart says it is a direct replacement for the factory actuator, and that all its other versions need tuning or calibration of the ECU. So have the 19 psi and 24 psi versions fitted with a tune, and set boost on a dyno, as Turbosmart recommends.
What does a twin port wastegate actuator do?
It adds a second pressure port to a separate chamber. Turbosmart says the pressure there works against the spring, giving a greater range between maximum and minimum boost than a single port actuator. The R35 Twin Port kit includes two actuators with a bracket and rod. Ask your tuner how the second port will be controlled.
What is the HKS actuator upgrade for the R35?
It is the strengthened actuator HKS fitted to its GT570 and GT600 R35 turbo kits, now sold on its own for a light boost increase or a repair, one for each side. HKS gives a set pressure of 88.3 to 93.2 kPa and says fuel re-setting is required, so plan a remap.