The waste gate stroke or lack of it ?

[Steve A]

I removed my waste gate actuator today to give it the "once over".
When I replaced it first making sure it was doing as it should, I was somewhat underwhelmed by the amount of movement it had when I applied air into the actuator.
Yes the gate moved freely
Yes the actuator moved freely (with a full stroke of 14mm).
Once it went back on the turbo it seems that quite a lot of "that stroke" (as you would expect) was used to keep the waste gate firmly closed.
I know the arm is adjustable but mine has never been touched and I would have thought factory set.
Your thoughts

[Simon_P]

It is just a flap and a hole. Most of its effect is when it is nearly closed after that it is diminishing returns. The limiting factor is when the area between the hole and the flap equals the area of the hole at which point the hole becomes the restriction - hence you make the hole bigger when porting the wastegate.

practically this equates to about 5mm opening on a fulcrum of 2:1 would be 2.5mm of actuator movement. So it is more important where it closes and there should be details in the manual.

[lotusflasherman]

I removed my waste gate actuator today to give it the "once over".
When I replaced it first making sure it was doing as it should, I was somewhat underwhelmed by the amount of movement it had when I applied air into the actuator.
Yes the gate moved freely
Yes the actuator moved freely (with a full stroke of 14mm).
Once it went back on the turbo it seems that quite a lot of "that stroke" (as you would expect) was used to keep the waste gate firmly closed.
I know the arm is adjustable but mine has never been touched and I would have thought factory set.
Your thoughts

Later actuator arms were fixed length, no adjustment possible.

turbo nb.jpg

rod.jpg

[Steve A]

It would be interesting to know what the length of the non adjustable one is, not really practical to check on the car though.
I was just a bit surprised that the movement was so small, not what I'd imagined it would be, but as long as it works as it should and it does