Let me know if you have one out of the car. I need to compare it with mine...

If you look into the top hole, can you see the spring?

 

See reply in your other post...


-Ted

 

Yep. Mine has a grey visible spring from the top port and is stamped 0.8-1.2 bar. It crackes open at 5 psig and is full open by 10 psig.

What I could not believe is how bad the pressure leaks down once the gate starts moving ... using a small bicycle handpump, you have to pummel the damn thing to keep the gate open while you hear all the air leaking out through the wastegate! On my car this WG cannot keep boost below 16 psig (above 5500 rpm) even with a line run directly from the turbo outlet to the side port of the WG, anybody got any ideas on how get the boost under control?

 

You sure it's "gray?"&nbsp Are you sure it's an HKS "RACING" 50mm wastegate?&nbsp I see the gray spring listed at 1.3kg/cm^2 or 18psi!&nbsp That's completely normal for the boost to be set at 16psi with this spring...



-Ted

 

You're right, mine spring is "yellow" based on the stamped pressure as well as bench testing. It simply looks grey looking thru the top port. Testing of the wastegate with a hand pump clearly shows the wastegate full open by 10 psig, not sure about the high amount of leakage though.

Testing the WG clearly shows the potential benefit of using a boost controller to aid spoolup. This 10 psig WG is 25% open at 5 psig! I assume the electronic boost controllers apply pressure above the diaphram to hold the WG closed until set boost is achieved, then vary the pressure above the diaphram to regulate boost thereafter.

Kyle

 

Yep, you are exactly right.&nbsp This is the reason EBC's are inherently superior to MBC's (there's a raging debate on this in the 2nd gen section right now).&nbsp The "boost ramp" is much more aggressive with an EBC...


-Ted

 

Sounds like you've got a hole in the diaphram, I've also seen the nut that bolts the shaft to the diaphram come loose as well...