Finally a full page and tech on our new wastegate actuators for the Evo's!
Why 26 psi base pressure? We want all the boost possible from an internal gate system.
You're not going to run this gate on your Grandma's old Buick, this is for getting the most out of a stock frame turbo, no "low boost" here
These come with every AGT Single Scroll Turbine housing equipped turbo we offer, When running this turbine housing, there's no reason not to have the most gate possible
First is wastegate pressure, a simple vacuum line from the boost reference source to the top port of the Internal Dual. (the Top port is the normal operation port of this wastegate actuator, same as a standard evo wastegate actuator)
This Allows the wastegate to open and regulate boost, once boost pressure reaches what the wastegate springs are rated for. In our case roughly 26 psi base pressure (may vary some)
This is a Simple way to regulate boost if you want an easy install, although you leave alot to be desired in terms of spool and potential power!
But, in a bind and needing to get the setup running and driving, this is easy and effective.
Most Common form of boost control, Pictured here is a Hallman Manual boost contoller, very common way of upping the boost over base pressure, and install is the exact same as with a standard internal wastegate, with a vacuum line to the top port and to the controller, and ofcourse the boost reference source off the turbo, to the other end of the boost contoller.
If you have a different brand boost controller, please refer that brand's install guide
Pictured here is a Grimmspeed 3 port ECBS. More commonly these are simple 3 Port MAC valves. And all 3 port MAC valves can be installed the same as this one.
If you have this type of boost controller already, then you'll be familiar with this setup.
This is the standard vacuum line setup for ECU controller boost through your 3 port ECBS,
Center Port #3 of the ECBS ran to the boost reference source
Left Port #2 to the top port of the wastegate actuator
Right Port #1 is left open to air
Now for the more uncommon vacuum line setups.
This are more commonly found in external wastegate installs, and this is where the Dual port wastegates really start to shine.
Just like an external wastegate, utilizing the opposite port on the gate can result in making more boost and better boost holding capability in the top end.
When using the top port alone like a standard internal wastegate, you can only take away so much boost reference pressure from that top port to make and hold boost before back pressure overcomes the system
But when combined with the bottom port, using a 3 port to direct boost pressure away from the top, and into the bottom port. Pressure at the bottom port, will actually help keep the wastegate stay shut.
-Vacuum line routing to 3 port ECBS-
Left Port #2 to bottom port
Center #3 Port open to air
Right Port # 1 is ran to a "T" Fitting that connects the top port and boost reference port together
This configuration offers very fine ECU boost control management while utilizing both ports
And now for the setup that will net the most of everything, Some refer to this as "3 port like 4 port"
utilizing all 3 ports on the ECBS in conjunction with the turbo and Dual port wastegate actuator. Boost reference doesn't get wasted in this configuration, all boost pressure that gets taken away from the top port, is completely directed to the bottom port to get THE MOST holding and boost making capability from an internal wastegate boost control system
For turbos like our 57mm, 62mm, and especially the 64mm, in our Single Scroll, Stainless steel turbine housing, this is what we recommend.
Not for everyone, but the built setups, ready to shoot for the moon
(or the Stock Block Hero's out there ***not recommended on stock block**)
This is what you want
you will have less resolution in the ECU boost controll tables, small Wastegate Duty Cycle changes will have a large Impact on boost increasing, but that is the trade off for the extra holding capability of this setup
When purchasing a Turbo with us and you have selected a wastegate to come with the turbo, We preload and install the wastegate for you, that being said there are some cases where you may need to add or take away some preload, depending on other supporting mods surrounding the turbo, but generally you wont have to touch this unless you are swapping wastegates or adding more for more boost holding capability
So what is Preload anyways?
Preload is the amount of force thats naturally on the Internal wastegate flapper system when the boost controller is not regulating boost. (idle,cruise,spool up)
By adjusting the threaded Rod end of the actuator rod, you effectively make the rod too short to slide onto the flapper arm. Having to pull on the rod end and compressing the springs in the gate, in order to get the rod end onto the flapper arm. This tension is what we call Preload.
If there's not enough preload and the rod end slides onto the flapper arm easily, this could cause the wastegate flapper to hang open, resulting in slow spool, not making enough boost, and poor boost holding capability.
Normally, for the MHi Twin scroll housing turbos, or the smaller 52 and 55mm turbos using the Single Scroll turbine housing, adjusting the rod end to be about 2-3mm to short is enough preload and works for the majority of setups running those turbos. and Not too much to cause boost spikes.
For the others, such at the 57,62, and 64mm in Single scroll, we add 1-2mm more, since these are going to be the turbos going for the most in this configuration
If you have a different preference, unsure if you have an issue with preload, or have any questions, feel free to reach out and ask! We are here for all your turbo questions!