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Either my search attempts are lame or there isn't any information. Always found the engine configuration interesting. All about it. Internet searches reveal this, i think he has the answer. From:germancarforum by Z4ever:
QUOTE:
But, if it's not flat plane... what is the Giulia Q's crankshaft configuration then?
So, is the Giulia Q's engine also an odd-firing V6 just like it happens with the current F1 engines where the 90 degree V6 layout and three throw crankshaft configuration is mandatory by the rules?
Is then the odd-firing engine responsible for the "burble or throaty, growling sound in the engine note" of the Alfa Romeo Giulia Quadrifoglio?

Answering to my own questions:

For as much I would like the idea of having a F1's IC engine on the Giulia Q, the extra vibration that an odd-firing engine would bring to what is, essentially, a road going car still is a factor that must be considered.

So, in short the Giulia Quadrifoglio engine's crankshaft has in fact three throws but with 30 degree split or offset journals/pins and that way the engine is able to fire evenly at each 120 degree of crankshaft rotation (instead of 90,150,90... and so on). What it does is to offset the prior firing angles of the two sets of rods/pistons, sharing a common crankpin (see picture below), by 30 degrees to either side of the crank rotation direction : delaying one, 90+30 = 120 degree; and advancing the other, 150-30 = 120 degree!!!



This is the three throw crankshaft of a 90 degree V6 engine where a single journal (circled in red) is shared by two sets of rods/pistons with one oil feeding hole for each.



This is basically the same crankshaft but with the journals offset or split by 30 degree (splay), also circled in red

'Split journal' crankshaft front view with the correspondent cylinder numbers: 1,2,3,4,5,6 from 90 degree banks


PS: My only doubt is how the above description fits to the Alfa Romeo's own description of the Giulia Q crankshaft: "super-finished forged nitride steel with single con-rod pin."

Thoughts? Clarification or confirmation would be great!
 

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You can look at Q engine as two joined 3 cylinder 120 deg engines....sich configuration is also neccessary if you want to shut down one bank of cylinders in A mode....triple 120 is extremely balanced type engine with big smooth torque and was for that reason used in numerous triple motorcycle engine configurations....we already discussed that in another thread somewhere....

It is definitely a brilliant design combining smoothness of triple 120 and traction benefits of big bang firing order when all 6 are firing
 
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