???.. The VR6 engine is a 15 degree V6 engine, with a single cylinderhead.
The W12 in the A8 and in some Bentleys has 4 rows of cylinders, paired at 15 degrees, then put 72 degrees apart, with 2 cylinderheads.
Makes PERFECT sense.
[quote=“RobtheFiend”]I would not be surprised if one of the cylinderheads of the AUDI/Bentley W-12 is identical to the one on the VR6 engine.
Maybe slightly redesigned to cope with the extra heat in the turbocharged Bentley.[/quote]
I know, I was referring to this post. No way the heads on a VR6 and W engine look alike.
They sure aren’t the exact same casting (for one thing the ports would need to come out different sides of each head, or you’d have one exhaust in the V and one on the outside of the V!)
But they DO appear to be very similar, here is a Bentley W12 head
And here is a VW VR6 head
They look pretty alike to me, at least in terms of overall dimensions, cylinder placement, combustion chamber design, shape of the head face etc. The only major difference I can see is that the water galleries are quite different between them.
1 Like
The Bentley is a turbo engine, maybe that is the difference.
And I wrote that ONE of the heads could be the same.
Maybe find a picture of a AUDI A8 W12 head? Could be interesting to see.
Andrew, I imagine a W12 or a VR6 as the modelling hell! 
abload.de/img/a-cutaway-of-the-w12-b1u06.jpg
Seems they are SOHC Heads… DOHC would be pure hell.
is DOHC on those even possible? those heads would be massive
[quote=“pyrlix”]Andrew, I imagine a W12 or a VR6 as the modelling hell!
Seems they are SOHC Heads… DOHC would be pure hell.[/quote]
Yes! Hell indeed.
I think if you look carefully they’re a weird sort of SOHC where one cam does the exhaust for BOTH rows of cylinders and the other cam does BOTH rows of intake on that side. So it has a seperate intake cam and exhaust cam like a SOHC, but it only has 1 cam for each row of cylinders… but it also has 2 cams per banks like a DOHC V12 would. I swear it’d be impossible to explain to anyone without a picture like that one!
It totally is DOHC then 
It’s DOHC per bank, but there are 4 banks, and only 4 cams, yet it’s still DOHC per bank… mind-blown
Maybe… maybe with DOHC it would be… QOHC!? (as in Quad)
1 Like
Well, looks like you made a fool of me again.
Hard to imagine that those engines are practical. I was looking at buying an Audi A4 from the like 02 I think that had a VR (no longer in use).
…only in Germany (and maybe Japan, maybe).
No VR6 on a A4 
The A4 uses a longitudinal engine layout - they use real V6s for it
1 Like
I think that all AUDI V6 are based on the first V8, eg. 90 degree. Even the V10 AUDI engines are 90 degree.
Wider engines, but more space between the heads for manifolds.
And then you have the Volvo V8, designed by Yamaha, 60 degree because a full 90 degree engine would not fit in the engine bay of the S80 Volvo. (transverse layout)
If I recall correctly the VR6 motors were used in any Audi that was a 3.2L capacity. So the Audi TT, the A3 and apparently at times in the Audi A8, A6, A4 and A5. Any other capacity of Audi V6 is a proper V6 mounted longitudinally.
And then you have THIS freak of nature… fourtitude.com/features/Miscella … prototype/
it’ll be damn complex to design such and definitely make it’s way as DLC
not sure whenever the use of the engine must obtain licensing from VAG or not