[Crawlings]

Originally Posted by theslik1

Technically, you're correct. Effectively, since the compressors are in parallel and balanced each one supplies 1.5 liters of displacement, equal to "3 cylinders each".

Which makes me wonder how exactly the turbos are balanced flow-wise, and what happens if one compressor is weaker than the other?

What do you mean supplies 1.5 liters of displacement each?? If you mean that the exhaust flowing through the turbo is 1.5 liters since it is powered by 3 cylinders, then remember that the wastegate valve is usually only fully closed at idle. Therefore unless you are at idle, you aren't going to get a full 0.5 liters of exhaust flow with each cylinder cycle. Also the compressor and the exhaust turbines are completely seperated flow systems connected by a turbine shaft only, therefore, the exhaust flow doesn't go directly back in to the engine anyways. (Which is a good thing )

Maybe I'm just confused about what you meant. There's a great sticky at the top of the page that will explain it better than I just did.

Chad

[theslik1]

All I meant was that the engine is 3.0L displacement; the turbo compressors are in parallel supplying a common intake header, therefore effectively supplying 1.5L of displacement each if they're balanced (equivalent to 3 cylinders volumetrically). I know they're not physically separate on the compressor side. Simple as that.

Which brings me back to the question of how the control system ensures that each turbo is doing its share and what happens if an imbalance occurs (i.e. a slow failure, like one of the compressors degrading more than the other over time).

Maybe Shiv can give us some insight when he's not installing Xede's.