I can not think of what it's called but its the rod on the turbo that you can adjust to make more boost. Is there a picture of it somewhere? Sorry to be so vague. 99 f350 7.3

 

The waste gate actuator rod. Visible in this picture. Must of us turn it in 7 turns.

 

You have to remove it to do so. Might was well replace it with a turbo master so you can adjust easily in the future.

 

And if you remove the turbo, replace the orings.. Turbo to pedistal.. Pedistal to block.. Also check your uppipes. Also check your metal fuel line that runs along the passenger side on the top. You can rebuild your turbo for ~$100 while it's out.

 

Yeah be careful about messing with the rod. Mine was swedged on there hard, and you can tear the membrane in the canister if just cranking on it like Hans Hamhands.

Another option is pull the red line off the canister and stick it on a convenient bolt. It will then open at it's max setting regardless of signal sent via vacuum.

Turbo Master or equivalent will allow you to dial it in, but to me that's too much effort for minimal reward.