A8 4.2 TDI Sport or S8?
Author
Discussion

whoopydoo

Original Poster:

7 posts

205 months

Thursday 15th October 2009
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I bought an A8 4.2tdi sport (MY08)back in March and it is a fantastic motor (I've had two 4.2 petrol versions in the past) with mpg of 30 - 38 and 5.9 to 60 it is a great luxury car. I live in a rural area and most of my motoring is on motorways and A roads, so I do get the odd opportunity to make use of the performance. However,I've read a few posts on the S8 and would like to know if anyone has driven both the 4.2tdi sport and the S8 and could give me an honest comparison with some pros and cons?

Dr G

15,991 posts

273 months

Thursday 15th October 2009
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Personally I didn't get on with the V8 tdi (i've not driven a 4.2 but have a 4.0) - strange sounding thing and couldn't achieve anywhere near the economy of a 3.0 tdi with only a small gain in performance, I felt it lost something in smoothness compared to the 3.0 also. Depreciation is comparatively frightening - amusing in that it's a bit of a daft engine but if you're going to have a daft engine why not have a Lambo dervied motor in a big old limo?

S8 is only slightly tweaked dynamically and cosmetically but did feel better composed when pressing on and that V10 is a lovely bit of kit (if too quiet). Really unusual sight on the roads and I like the feeling of driving something different and special. Performance is very, very good but does not feel it - like sitting in an armchair whilst altogether very naughty number appear on the speedo. Standard kit on the S8 is fairly serious too.

If I was covering miles I'd have a 3.0 and maybe a remap - for the 'fun' or plaything option I'd go S8 - V8 TDI is neither six of one nor is it a half dozen of the other frown

james S

1,620 posts

276 months

Thursday 15th October 2009
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Not sure how valid this is but Audi in Amersham told me the 4.2 TDI is the same latest generation technology as the 3.0 TDI whilst the 4.0 is an older generation engine.


Dr G

15,991 posts

273 months

Thursday 15th October 2009
quotequote all
That wouldn't surprise me actually - I've not driven a 4.2 TDI yet.

whoopydoo

Original Poster:

7 posts

205 months

Thursday 15th October 2009
quotequote all
I drove the 4.0 tdi when it first came out. It produced 275bhp as opposed to the 4.2's 325bhp plus 650nm of torque. The 4.2 is certainly a lot faster.
Also the 4.0 seemed to have a strange vibration back through the accelerator pedal when at idle.
I drove a 3.0 tdi for a week as a courtesy car when my previous shape 4.2 petrol was in for some work. By comparison the 3.0 tdi felt rather pedestrain.
On the subject of depreciation, it is very heavy. When I bought my 4.2tdi it had lost 53% of its value in a year and 12k miles. So second hand, it was a bargain!

From what you are saying, as an everday 30k miles a year car, is the S8 worth the extra fuel?

Tame Technician

2,467 posts

235 months

Thursday 15th October 2009
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S8 is a fantastic car.

If you can afford the fuel costs get one of them, you wont be disappointed.


Dilligaf10

2,431 posts

241 months

Thursday 15th October 2009
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james S said:
Not sure how valid this is but Audi in Amersham told me the 4.2 TDI is the same latest generation technology as the 3.0 TDI whilst the 4.0 is an older generation engine.
4.0 is the old generation engine. 3.0 & 4.2 TDI both have piezzo injection technology. I tried a 4.0 before buying the 3.0 TDI and I thought it was a real rough engine and felt gutless. My 3.0 is chipped and it has made a world of difference. Still hankering after a 4.2 TDI when I change this one for what it's worth

whoopydoo

Original Poster:

7 posts

205 months

Friday 16th October 2009
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What do you actually get to the gallon from the S8?

Tame Technician

2,467 posts

235 months

Friday 16th October 2009
quotequote all
Only see 2 or 3 of the V10's, they showing 14-17 ish on the average.

Book says just over 20 I think, should be on the Audi UK website.


asman0161

124 posts

223 months

Saturday 17th October 2009
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I have the pleasure few times a month when i get my hands on the keys to the chipped 08plate 4.2tdi sport and 56plate s8 interior wise exactly the same apart from badges/emblems. Both have 20" wheels on them so handling wise they are the same.
In a straight line from standstill and from a roll the tdi blows the s8 by 2 car spaces.
s8 sounds nice at full throttle but is a bit too quiet.
My money would take a fully loaded 4.2tdi sport, the chip is only one of them cheap ones you get done for £500.
Plus on the motorway doing 90mph you get 40mpg on the tdi full tank about £80, local heavy footed driving easily 400 miles on a tank and motorway computer says 700miles.

AKA8

1,849 posts

258 months

Saturday 17th October 2009
quotequote all
asman0161 said:
I have the pleasure few times a month when i get my hands on the keys to the chipped 08plate 4.2tdi sport and 56plate s8 interior wise exactly the same apart from badges/emblems. Both have 20" wheels on them so handling wise they are the same.
In a straight line from standstill and from a roll the tdi blows the s8 by 2 car spaces.
s8 sounds nice at full throttle but is a bit too quiet.
My money would take a fully loaded 4.2tdi sport, the chip is only one of them cheap ones you get done for £500.
Plus on the motorway doing 90mph you get 40mpg on the tdi full tank about £80, local heavy footed driving easily 400 miles on a tank and motorway computer says 700miles.
Seems slightly odd given that the S8 is quoted as being over half a second quicker on 0-60mph. Marketing spiel by Audi perhaps?

ukdennis

167 posts

249 months

Saturday 17th October 2009
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I think the difference is down to the remap on the 4.2tdi. Can't recall the exact figure, but I think it's around the 800nm mark (up from 650nm standard) which would make it a monster.