[John_K_348]

I saw this in a documentary on the 488. I have heard from a Quad owner that the Giulia V6 block is taken from a 488 with 2 cylinders removed, not just a Cali T. This might be true if they are in fact the same block. They also said the turbos are the same or run the same boost at 30psi. If all of this checks out and this video is accurate, then this compressor looks like it has 2 sets of blades in close succession, or "twin" arrangement. Is this a twin scroll turbo?

 

[lockem]

I saw this in a documentary on the 488. I have heard from a Quad owner that the Giulia V6 block is taken from a 488 with 2 cylinders removed, not just a Cali T. This might be true if they are in fact the same block. They also said the turbos are the same or run the same boost at 30psi. If all of this checks out and this video is accurate, then this compressor looks like it has 2 sets of blades in close succession, or "twin" arrangement. Is this a twin scroll turbo?

Not according to this guy:

He says a twin scroll turbo charger has one set of driving (maybe the wrong nomenclature on my part) blades and one set of driven (compressor) blades, and the "twin" part comes into play in the housing that feeds the exhaust into the driving blades.

 

[lost1750GTV]

http://www.superstreetonline.com/how-to/engine/modp-0906-twin-scroll-turbo-system-design/

 

[John_K_348]

Watching now. That guy is good, especially with F1 tech. Thanks.

...

Very cool. So it's like a dual geometry turbine flow to handle two rpms ranges. Almost like bypass ratios in turbo fans on the compressor side. High bypass vs. low bypass. The main difference between jet fighter and cargo jet engines today. High bypass is better for low speed high volume/thrust. Low bypass was better in the Century Series years for high speed supersonic aircraft. Better than the older centrifugal style compressors in the Sabre and MiG-15. They were more stout, wider and harder to push to supersonic speeds...
So the "scroll" refers to the loop of channels feeding the turbine. That's kinda cool. Now I wonder about the apparent dual blades on the compressor in the 488. It might be a similar consideration but different solution. Sort of like a single channel air inlet, but "twin blades" acting like wing and slat on the compressor side to handle different speeds or "angles of attack" in the inlet pipe. Possibly due to different travel and intake-flowpeeds of the vehicle.