Im about to upgrade my headers and one of the mechanic in the shop suggesting that i should have 2 wastegate for the stock twin scroll turbo.
My questions are:
1. Is it recommended to have a dual wastegate for a twin scroll turbo?
2. What are the advantages and disadvatages of this kind of setup?

any suggestion/comments would be very much appriciated.

 

If you're doing external gates off the manifold, you need two because the manifold will be divided for the twin scroll turbo. But, stock turbo has an internal waste gate, so you don't need waste gates in the manifold. If you want and external gate, you can just do it off of the O2 housing, MAP makes that set up..

 

you don't need to change your wastegate for just changing your manifold (header) and keep the stock turbo because stock turbo has internal wastegate. You would have to modify your hotside of your turbo if you wanted to run external wastegate which would be a waste of effort

 

No. On an inline four cylinder engine the word "header" is never a plural. There is only a single header on our Evos.

 

lol True that. I have a question about dual wastegates, say I had two wastegates with 14psi springs. That would be enough to hold about 60 psi, correct? What does that have to do with running the lowest amount of boost?

 

lowest psi is 14.

You don't add the two springs up to make out what the spring pressure would be (which I assume you did to come up with 60psi since the rule of thumb is typically 2-2.5x spring pressure for max psi).