Originally Posted by simon021
The entire point of an External wastegate is rock solid boost. I wouldnt expect anything less than that, no matter how you are controlling it.
You should be able to slam that thing up to target boost and hold it rock steady. When I switched over to the Hybrid method, I only picked up maybe 150-200 rpms of spool if even that. Most logs you couldnt even tell a difference depending on where I started the log at.
I sold the MBC because I didnt see the benefit to the hybrid system with an external wastegate. It's already solid enough. Theres not enough gain for the complexity of the system in my opinion.
An electronic boost controller uses a pulse modulation to control the wastegate. It cannot simply "hold it open" at a specific spot. It has to open and close very rapidly. If it's quick enough you don't hear it much, but usually with an external dump it's pretty obvious. You can still hear it in your video, but only slightly. It is actually impossible
for an EBCS to not
flutter. Certain things may make it less obvious, but it is pulsing, that is how it works.
A MBC will not flutter. It is a spring loaded ball that lifts depending on how much pressure it sees.