ok, so i have seen MULTIPLE setups that utilize a dual wastegate system. i am just wondering why they use 2 of them. the only 2 reasons i can come up with are either:

a.) They are on a twin-scroll manifold, so each set of 2 runners needs a wastegate because all 4 runners do not end up merging into 1 collector

or

b.) They use low pressure wastegate springs to control traction at low speeds, but want to run EXTREAMLY high boost levels up top and do not want any wastegate fluctuation.

can anyone help me out understanding why you would run 2 wategates?

 

a)

 

And C) To help eliminate boost creeps on big turbo lower boost setups when one gate is maxed out, flow-wise.