13. Mar, 2019

Wastegate actuator upgrade

HOLDING BOOST PRESSURE FOR LONGER

An internal wastegate has valve is built into the turbine housing.The wastegate valve is controlled by an actuator.

This valve bleeds exhaust pressure before the turbine wheel to get the turbo to boost the pressure desired.

Internal wastegate actuators are made up of a sealed canister with a diaphragm and spring, with a rod connected to the valve inside the turbine housing

Upgraded internal wastegate actuators are highly adjustable, with a wide variety of springs available . 

Made from high quality materials which can withstand high stresses and temperatures for prolonged periods.

They have silicone diaphragms with nomex reinforcement to withstand high working pressures and high temperature. 

Providing better turbo response and greater sensitivity when managing boost pressures. 

Choosing the right spring is important , you will need 50% of your intended boost setting .

On a 1,5 bar map it will be a 0,75 spring. Or even a little lower as you can preload these springs.

Now this is where the dilema comes in, factory boost targets are set quite low for engine reliability.

On a factory boost setting of say 0.7 bar boost , you might have an actuator that is preset to 0,3 bar, when you try and turn up the boost via software you will have a difficult time controlling the boost over the whole rev range.

The valve might even be blown open due to turbo inlet pressure getting too high. Waistegate duty cycles will have to be maxed out to even try and control it.

Springs can be interchanged by opening the canister and resealing it after intallation of the new spring.

Its really advisable to set  your opening pressure using a wastegate setting tool.

Just a word on preload, the amount of preload in mm's wil take away from the distance the valve will open inside the chamber.