raising boost, stock wastegate, EVC's.

[MarkRobinson]

Is the stock wastegate a limit because there's only one port on it making EBC's less precise, or are the "shims" a better solution.

"Way back when", the banjo bolt fittings were the way to raise boost.

[88BlueTSiQuest]

Banjo bolt fittings run the same way as an MBC and EBC. They all limit the amount of boost pressure to the wastegate, allowing you to run higher PSI's.

The deal with the wastegate is that it's practically 'Fail Safe'. The exhaust pressure will actually overcome the wastegate spring, and open it prematurely. This is why there are shims, and different wastegates on the market. The shims basically set the valve up further into the chamber, so that when the wastegate valve starts to move, it has to go further before the pressure is released. It can actually limit the exhaust flow, as the valve can no longer move as far as it could from the factory.

It's a decent design for the everyday person, but from a performance stand point, it actually sucks, as there isn't a way to keep the stock wastegate closed until you need it to open.

This is why you see that most everyone upgrades the wastegate, to either the LR upgrade or they run a Tial. I will eventually go for a Tial myself.

[nize]

shimming the wastegate, restricting the banjo bolt, using an mbc/ebc, or any other method of raising boost that involves disabling/bypassing/restricting the cycle valve without implementing some other form of knock protection can cause engine damage if you don't fully understand what you're doing. read this;
bypassing cycling valve