Is there any way to reduce the amount of boost on a stock td05 dsm turbo and if there is how? And if i wanted to get a new wastegate what happens with the door the stock wastegate connects to?

 

to reduce boost, get a boost controller, if you want to make the turbo have an external wastegate you need to remove the flapper door and the downpipe must cover it and have a good seal or weld the wategate hole shut on the turbo exhaust housing........

 

You can also just bypass your stock boost solenoid and hook up directly to the wastegate if you only want to lower your boost.

 

i think he wants boost lower than the stock wastegate regulated (8 psi), the boost solenoid brings it higher to like 12 i think. boost controllers only increase boost not decrease it. only way to decrease it would be to go external or get a new actuator with a lower spring rate. good luck on finding a new actuator with a lower boost rating than yours, but you can do what i did and take it apart and cut the spring, i got mine down to 5 psi like that. now i have a manual boost controller so i can set it from 5psi on up.

 

its easy, all you have to do is bend the actuator bracket inward about 1/4 inch that should give you between 4 to 5 psi

 

you cannot lower boost with an MBC, only raise it. if you want to understand why, look into how they are made. the best way to lower boost is with an external wastegate setup.

 

Boost will NOT go lower than the setting on the wastegate get a new flapper or convert to an external and get a 4psi spring in there. but then agian if you only want 3-4 psi why did you buy a turbo car?