Quote:
Originally Posted by madfast
yes, basically. i believe porsche/borg warner use proprietary materials and that's why they're the only ones who use variable vanes. and even then, there are stories of the vanes failing...
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This thing is a Garrett VNTxx. My co-worker's TDI threw a rod at only 18x,xxx kms and he said something about replacing his turbo with a bigger one.
I heard "VNT" and offered him $50 for the old one, wanting to see what a Garrett variable geometry system was/how it worked. Didn't know the damned thing was attached to the manifold...
My understanding is that Garrett's is only a single big vane and is the least efficient (lots of turbulence) of the variable geometry setups.
Second best I've heard is the Mitsubishi which is similar but two vanes that open sequentially and 'backwards' compared to Garrett's VNT. Supposed to be very efficient and very reliable. Is this on USDM Evos? It is apparently on certain JDM models.
Porsche's multi-vane is supposed to be the best performing.
The twin-scroll thing puzzles me as to why it is even a buzz-word. My understanding is that it is just a twin-entry divided turbine, the same as Toyota was using with the CT26 ~
25 years ago, or am I missing something?