# W8 vs W12??



## B5Speedo (May 2, 2001)

Except for the extra 4 cylinders are there any other mechanical differences between these two engines? Such as cam, valve, etc designs? Not including any ECU programming differences.
TIA,
Tom


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## bigdude (Apr 16, 2009)

*Re: W8 vs W12?? (B5Speedo)*

I feel confident with a w12-because there is no timing belt-cams are gear driven-less maintanence


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## Itzmann (Jan 16, 2006)

*Re: W8 vs W12?? (B5Speedo)*

Somebody correct me if wrong... but isn't the V8 an Audi engine whereas the W12 is a VW original concept, with a legacy design philosophy coming all the way from the 15º narrow-V VR6 from 1991?


_Modified by Itzmann at 6:39 AM 6-20-2009_


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## maverixz (Feb 16, 2005)

Based on my limited knowledge, both engines are shared between the high echelons of the V.A.G family. The W12 first came into production in 2001 for the A8 but was not available in the North American versions.


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## B5Speedo (May 2, 2001)

*Re: W8 vs W12?? (bigdude)*


_Quote, originally posted by *bigdude* »_I feel confident with a w12-because there is no timing belt-cams are gear driven-less maintanence

There is no timing belt in the W8 either. It's all chain driven.
IIRC the W16 in the Bugatti Veyron is basically two W8s together with 4 turbos.
Audi decided they didn't not want the W8 and designed the 4.2L V8 instead for more horse power.


_Modified by B5Speedo at 11:19 PM 6-19-2009_


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## chrisj428 (Feb 26, 2005)

*Re: W8 vs W12?? (B5Speedo)*

Tom,
There are HUGE differences between the two engines.
For starters:
V8 4.2 litre
* 90° angle design
* 5 valve per cylinder heads
* Timing belt
* Shares architecture with the 2.8 litre 40 valve V6 engine in Passats, et. al.
W12 6.0 litre
* 70° angle design (90° effective angle, outer bank to outer bank)
* 4 valve per cylinder heads
* Timing chain
*Share architecture with the 4.0 litre 32 valve W8 engine in the Passat.
The VR6 engine was designed in response to Wolfsburg wanting a V6 engine in a transverse mount application (i.e. Mark III GTI). There was enough room in the latitude direction, but front-back spacing was going to require a redesign. So, the engineers developed a 15° V6 engine with one cylinder head. Because this engine shared architecture with both "v" engines and inline engines, it came to be known as the "VR" engine (with the R standing for Reihen, German for "in a line").
When the D1 (Phaeton) was evolving, now the engineers wanted to put a 12 cylinder engine in a vehicle without extending its proboscis. Again, there was plenty of side-to-side room. They took the VR design and adapted it to a longitudinally-oriented application and the W12 was built (after being test-muled as a W8 in the Passat first -- simply a means to an end).


_Modified by chrisj428 at 1:48 PM 6-22-2009_


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## chrisj428 (Feb 26, 2005)

*Re: W8 vs W12?? (chrisj428)*

NB: The only VR architecture engines available in the Phaeton were the 3.2 litre VR6 and the 6.0 litre W12. The other engines (3.0 litre TDI, 4.2 litre petrol and 5.0 litre TDI) are all in a conventional "V" arrangement. The W8 was never available in the Phaeton.


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## B5Speedo (May 2, 2001)

*Re: W8 vs W12?? (chrisj428)*


_Quote, originally posted by *chrisj428* »_NB: The only VR architecture engines available in the Phaeton were the 3.2 litre VR6 and the 6.0 litre W12. The other engines (3.0 litre TDI, 4.2 litre petrol and 5.0 litre TDI) are all in a conventional "V" arrangement. The W8 was never available in the Phaeton.

Chris, 
You are reading too much into my question. All I want to know are the differences between the W8 and the W12 engines besides the cylinder number. 
The W12 produces 70hp/L. The W8 produces 68hp/L. Is the W8 just detuned through the ECU or are there machanical differences between the two engines? I would have expected the hp/L of the W8 to be higher than the W12.


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## chrisj428 (Feb 26, 2005)

*Re: W8 vs W12?? (B5Speedo)*


_Quote, originally posted by *B5Speedo* »_All I want to know are the differences between the W8 and the W12 engines besides the cylinder number.

The W12 in the '06 and higher Phaetons has a dry-sump lubricating system whereas the previous engines (and the W8) do not.
The W12 has reduntant controls for each bank of cylinders, whereas the W8 does not.

_Quote, originally posted by *B5Speedo* »_The W12 produces 70hp/L. The W8 produces 68hp/L.

Which W12? The dry-sump W12 produces 74hp/L. Given that the W8 was the first production engine in the series, I'd expect each successive permutation to be more efficient in one area or another.


_Modified by chrisj428 at 4:26 PM 6-22-2009_


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## B5Speedo (May 2, 2001)

*Re: W8 vs W12?? (chrisj428)*


_Quote, originally posted by *chrisj428* »_The W12 in the '06 and higher Phaetons has a dry-sump lubricating system whereas the previous engines (and the W8) do not.
The W12 has reduntant controls for each bank of cylinders, whereas the W8 does not.
Which W12? The dry-sump W12 produces 74hp/L. Given that the W8 was the first production engine in the series, I'd expect each successive permutation to be more efficient in one area or another.
_Modified by chrisj428 at 4:26 PM 6-22-2009_

Redundant controls???? What is that?
So I guess it's all in the electronics when comparing the initial W12 with the W8.


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## MadMacStew (Apr 20, 2009)

*Re: W8 vs W12?? (B5Speedo)*

Can we just take a moment to review which engines go in which models? To be clear, the VW VR6 engine was *never* available for the Phaeton, that (truly excellent) 3.2 V6 is the longitudinal Audi engine used in various models from A4 to A8, while the only Audis which ever used the VR6 were the A3 and TT. 
Equally, the 4.2 V8 used in the Phaeton is an Audi engine, the short-lived 4.0 W8 was only ever used in the flagship version of the VW Passat, being replaced there by the stretched 3.6L VR6.
The mighty 6.0 W12 is used in the VW Phaeton and Touareg, the Audi A8L, and in twin-turbocharged form, the Bentley Continental range. It's also supplied to Spyker for use in their limited production supercars.
Finally, to answer the original question, the W8 and W12 engines do share the same architecture as the VR6, being 15 degree V banks with chain-driven cams, 2 cams per bank.


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## PowerDubs (Jul 22, 2001)

*Re: W8 vs W12?? (MadMacStew)*


_Quote, originally posted by *MadMacStew* »_To be clear, the VW VR6 engine was *never* available for the Phaeton

'To be clear', the 3.2 VR6 *IS* the petrol V6 that was in the Phaeton.
You can see the intake manifold in a picture here on VW's website-
http://www.volkswagen.si/model...on_v6/
and here is a screenshot of the Etka parts breakdown








I still find it funny that they use the same engine in this 5300 pound car as they put in my Golf.


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## chrisj428 (Feb 26, 2005)

*Re: W8 vs W12?? (PowerDubs)*


_Quote, originally posted by *PowerDubs* »_'To be clear', the 3.2 VR6 *IS* the petrol V6 that was in the Phaeton.

Cheers!


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## MadMacStew (Apr 20, 2009)

*Re: W8 vs W12?? (PowerDubs)*


_Quote, originally posted by *PowerDubs* »_
'To be clear', the 3.2 VR6 *IS* the petrol V6 that was in the Phaeton.
You can see the intake manifold in a picture here on VW's website-
http://www.volkswagen.si/model...on_v6/
and here is a screenshot of the Etka parts breakdown








I still find it funny that they use the same engine in this 5300 pound car as they put in my Golf.









Oh rats - as Jack Nicholson once said, "don't I feel the f*&^% *******"!








OTOH, another score for the forum, and I learned something today! http://****************.com/smile/emthup.gif 
I guess there is some logic in the 6 really and truly being half of the 12, and yes indeed, it is hopelessly underpowered in the Phaeton - but great fun in an A3, which I had a couple of years ago.










_Modified by MadMacStew at 5:39 AM 6-24-2009_


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## Highline (Mar 13, 2003)

*Re: W8 vs W12?? (Itzmann)*


_Quote, originally posted by *Itzmann* »_Somebody correct me if wrong... but isn't the V8 an Audi engine whereas the W12 is a VW original concept, with a legacy design philosophy coming all the way from the 15º narrow-V VR6 from 1991?

_Modified by Itzmann at 6:39 AM 6-20-2009_

The W12 is a AUDI engine, first developed for some concept car in early '90s. 
It was even available on the AUDI A8 before the concept of the VW Phaeton (or D1) was ever made public.


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## Highline (Mar 13, 2003)

*Re: W8 vs W12?? (MadMacStew)*


_Quote, originally posted by *MadMacStew* »_Can we just take a moment to review which engines go in which models? To be clear, the VW VR6 engine was *never* available for the Phaeton, that (truly excellent) 3.2 V6 is the longitudinal Audi engine used in various models from A4 to A8, while the only Audis which ever used the VR6 were the A3 and TT. 
Equally, the 4.2 V8 used in the Phaeton is an Audi engine, the short-lived 4.0 W8 was only ever used in the flagship version of the VW Passat, being replaced there by the stretched 3.6L VR6.
The mighty 6.0 W12 is used in the VW Phaeton and Touareg, the Audi A8L, and in twin-turbocharged form, the Bentley Continental range. It's also supplied to Spyker for use in their limited production supercars.
Finally, to answer the original question, the W8 and W12 engines do share the same architecture as the VR6, being 15 degree V banks with chain-driven cams, 2 cams per bank.

1. The 15 degree 3.2L VR6 engine was available on the Phaeton since the car was introduced in 31 May 2002. Later the engine was replaced with the 3.6L VR6. 
The same 3.2L engine is used in the VW Golf R32, both MkIV and MkV, the Passat B6, the Touareg and Porsche Cayenne (replaced later by the 3.6 on both), and as you said Audi A3 and TT. 
I find it hard to believe that the AUDI 3.2L V6 engine was used in the Phaeton instead.

2. The W12 engine is a AUDI developed and first used engine, both in a prototype (even before the VW W12 concept in 1996) or a production car (the A8 W12)
3. The W8 on the Passat was replaced as top of the line engine when the B6 came out by the 250HP 3.2L FSI. Only USA and Canada got the 280HP 3.6L version. 
Of course then came the R36 with the 300HP version of the 3.6L engine and the CC got only the 3.6L with 280HP on the North American models and 300HP + DSG in the ROW models


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## Prince Ludwig (Mar 24, 2007)

_Quote »_2. The W12 engine is a AUDI developed and first used engine, both in a prototype (even before the VW W12 concept in 1996) or a production car (the A8 W12)

Not quite - the W12 engine that Audi first mentioned for the Avus concept was a traditional W12 with three banks of four cylinders. The W12 engine is very much a VW-designed engine, it's just that until the Phaeton there was no VW-branded product to put the thing in.


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## PowerDubs (Jul 22, 2001)

*Re: W8 vs W12?? (Highline)*


_Quote, originally posted by *Highline* »_
The same 3.2L engine is used in the VW Golf R32, both MkIV and MkV, the Passat B6, the Touareg and Porsche Cayenne (replaced later by the 3.6 on both), and as you said Audi A3 and TT. 

Don't forget the EOS.


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## B5Speedo (May 2, 2001)

*Re: (Prince Ludwig)*

Not that Wiki is always correct but here is a little more infomration that contradicts much of what was said above.

_Quote »_
At the 2001 Tokyo Motor Show, Volkswagen showcased the W12 Coupe, a mid-engined, rear wheel drive supercar powered by a 6 L W12 engine producing 512 hp. A week before, the W12 Coupe broke the world 24 hour endurance record. A total distance of 7085.7 kilometres (4402.8 miles) was covered at an average speed of 295.24 km/h (185.45 mph), breaking the old record by 12 km/h (7.5 mph). Production of the W12 Coupe was considered but is currently cancelled.
The 6.0-liter W12 is a compact engine arrangement used in the Volkswagen / Audi AG vehicles, A8, Phaeton, and Continental GT and GTC. The "double-vee" arrangement allows for a small overall size in comparison with a tradition V- or Flat 12 engine. This engine made its debut in 1997 Volkswagen W12 Nardo concept supercar at the Tokyo Motor Show. The arrangement is also used in the 4.0-liter W8 used in the 2004-2006 Volkswagen Passat and the 8.0-liter W16 of the Bugatti Veyron 16.4. 
Technical 
The Nardo version of the W12 was 5.6-liters in displacement with a length of only 20.1 inches, and a width of 27.6 inches. It produced a claimed 420 hp @ 5800 RPM and 390 lb-ft of torque @ 3000 RPM. 
The Volkswagen Phaeton W12 uses a detuned version of the A8 engine producing 444 hp @ 6000 RPM and 406 lb-ft of torque at 3250 RPM. The compression ratio is also lower at 10.5 : 1. 
The Bentley Continental Flying Spur, Continental GT and Continental GTC all use a twin-turbocharged version producing 552 hp (560PS/411kW) @ 6100 RPM and 479 lb ft (650Nm) of torque @ 1600 RPM. The compression ratio of this version is 9.0 : 1.

Volkswagen Group currently produces W12s based on two of its narrow-angle VR6 engines. The narrow angle of each set of cylinders allows just two camshafts to drive each pair of banks, so just four are needed in total. Note that this design differs from the W18 engine that Volkswagen produced for its Bugatti concept cars of 1998 and 1999. Due to this distinction, the VW Group's W12 engine is sometimes described as a "WR12".
The VW W12 is used in some high-end luxury models:
Audi A8 
Bentley Continental GT 
Bentley Continental Flying Spur 
Spyker C12 LaTurbie 
Spyker C12 Zagato 
Spyker D12 Peking-to-Paris 
Volkswagen Phaeton 
Volkswagen Touareg W12 




_Modified by B5Speedo at 9:56 AM 6-26-2009_


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## Highline (Mar 13, 2003)

The W12 (Nardo) supercar had 600 HP and not 512. The first prototype of the car apeared in either 1997 or 1996.


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## B5Speedo (May 2, 2001)

*Re: (Highline)*


_Quote, originally posted by *Highline* »_The W12 (Nardo) supercar had 600 HP and not 512. The first prototype of the car apeared in either 1997 or 1996.

http://www.supercars.net/cars/1872.html

_Quote »_The Italdesign Giugiaro study of the W12 Coupe, which is systematically oriented towards top performance and high levels of driving dynamics, is the third phase of evolution of two W12 concept cars becomes the fastest cars in the world. 
The W12 Syncro prototype was first unveiled at the 1*997 Tokyo Motor Show,* while the 'roadster', a more advanced version of the W12 Syncro, made its debut at the Volkswagen stand at the *1998 Geneva Motor Show.* The final evolution of this sports car project, with its W12 engine inspired by the world of motor sports, was showed at the last Tokyo Motor Show and now is entering the decisive phase of production development.
.


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## Aren Jay (Jun 9, 2009)

*Re: (B5Speedo)*

Given that there is some concensus that the W8 and W12 have some similar background. (ad far as my limited understanding of these proceedings is concerned) is it true to say that the W16 is also of this same mold or of a V8 (twined) design?


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