Originally Posted by Torgus
When they are working as they are supposed to work, yes they do perform the task they are their for, quicker spool, and more top end. But from what we have seen, they are slowly getting phased out. Ford used them for a while, now they do not in the newest stuff. The ford 6.0 diesel VGT was a disaster, they get stuck often, causing low power conditions. VW used them in just about every turbocharged vehicle they made, they used Garrett unit, we just upgraded two 2015 units for a customer in South Africa, the Golf R's and the new GTI's both went away from the VGT and are no longer garrett unit. Just about everything we see if going away from them into more small frame Twin Scroll design. They really are that problematic, they are MANY small moving parts that are sitting directly in the exhaust, a lot of these are on diesels, that soot and exhaust just coat everything and they stop moving. I would not be surprised to see them gone soon. Porsche still uses them on the 997's. We have yet to see one, so they are most likely a better design, but we have seen about 10 different designs from differing manufactures, some are simple and much less prone to failure, some are just plain bad designs. I think the electric turbo to help spool is where the future would be heading over VGT. "