What are the real differences between the S8 and the S6

A6 All/ S6 All
#1 
I know a few people have ask me the real difference between the S6 V10 and S8 V10 and to be honest I don't think there is a real difference. When you look at each car and each difference the only real differences come in a few parts. I'll post the differences when I can load more pictures. The only noticeable difference. The S8 has better air box flow and the S8 has a better smoother exhaust system in the cat back section. Other then those few things the only real mechanical difference is in the total gear ratio. Before we get too far into the conversation here is the tail of the tape between the two cars. They are much closer than you would think.           



              V10 S8 ---- V10 S6
    Hp           450   ---   435
    Tq           398  ----   398

  Comp raito 12.5:1 -  12.5:
      Bore      3.33in --- 3.33in
     Stroke    3.65in –- 3.65in

     CID      318 CU – 318CU  = 5.2L

Block aluminum – aluminum / Heads aluminum – aluminum / Crankshaft Forged steel
12 5:1 compression. Firing order 1-6-5-10-2-7-3-8-4-9

Transmission gear raito.

         S8   ------  S6

1st 4.171:1 - 4.171:1
2nd 2.340:1 – 2.340:1
3rd 1.521:1 – 1.521:1
4th 1.143:1 – 1.143:1
5th .867:1 — .867:1
6th .691:1 — .691:1
FD 4.055:1 – 3.801:1

     Total weight 
   S8 -------- S6

4586lbs — 4486lbs

CAPACITIES of the S8 and S6

Engine oil 10.6 Quarts Both.

Fuel tank S8 – S6
23.8 – 21.1

Over all length S8 ---- S6
16.5’ 16’

 Width   S8 ----- S6
            6.25’ --  6.5’

Height S8 — S6
4.675’ — 4.75’

Breaks Front S8 — S6
385 MM — 385 mm or 15.2”

Rear
335 MM – 330 MM or 13”

Both cars are limited to 155mph
Both share the same turning radius

http://audirevolution.net/addons/albums/images/433331063.jpeg

http://audirevolution.net/addons/albums/images/702456259.jpg

http://audirevolution.net/addons/albums/images/25270200.jpg

Audi of America distributed to dealers and outlets. It includes over all width with Mirrors.

http://audirevolution.net/addons/albums/images/447810987.jpg

The front breaks are the same and that’s a big deal. I felt my JHM lightweight rotors were well worth the weight savings and helped the car gain a more nimble nature.

I’ll post more later. This was just a quick conversation starter.

#2

Reserved for pictures.

#3

Subscribed. I always knew the air box was a little different on the s8. Interested to see the s6 is actually wider, but taller.

Not exactly the point of the post but I hear the c6 s6 is a tiny bit easier to work on and gain access to things in the engine compartment.

I drove a d3 s8 this past weekend and even though dimensions are similar the s8 felt much bigger, and slightly more isolated. Good and bad depending on what your looking for. Still impressed none the less though especially for the size! Trunk also seemed wider and bigger in the s6, but that’s not quite about performance :slight_smile:

#4

I would also think because the s8 is all aluminum it is slightly less suspecting to heat soak. Would be interesting to try and prove that though.

#5

One of the tangible differences between the S6 and S8 is that I have never owned an S8 :wink:

#6

I think the aluminim body is to save weight. I think the extra weight is from all the electronic stuff they add. I dont think the body helps redue to prevent heat soak

#7

Coming from a D2 S8 and then an A8L, I definitely believe the aluminum structure plays an enormous factor in the (lack thereof, in those cases) heat retention. No doubt in my mind whatsoever.

I found it interesting that the C6 specs out to be quite similar to a D2 in most dimensions, except again taller. I’m shocked how big the Cbody cars have grown.

Interesting about the negligible weight disparity between the two, and the taller gearing in the '8. Fun stuff, thanks for sharing.

I’d venture a guess that the steering ratio in the '6 is a shade quicker as well - but again, just my SWAG :sunglasses:

#8

If we can’t find drag coefficient, I have a tool/calculator that will give us a pretty close value if given the data points for frontal area, horsepower and aero limited top speed.

#9

^awesome^

still intriguing (and equally surprising) that these are so similar in size / spec, yet different

and I continue to wonder on their steering ratios.

Me, I’m mostly jealous of the larger tank in the '8 - mah range is teh suk (FTMFL!) :sunglasses:

great group 'o gentz here - keep on keepin on

#10

Very Cliff Claven

#11

Nevermind, the B9 A4 is now 187" long!

B5 176"
B67 181"
B8 186"
B9 187"

Its getting to be C5 sized. Pretty much already is.

#12

Me too. Plus I wanted to talk about this, this weekend.

http://audirevolution.net/addons/albums/images/619428370.jpg

Starting to break down the read differences between the S6 and S8 further. That is the S8 exhaust on top of the S6.

#13

Piping looks smoother with slightly less bends and well dents :slight_smile: not sure why they did, it should have fit anyways. Does the diameter of the piping look a touch larger as well?

#14

badass - thanks for posting that, Count

wonder if the '8 rear cans flow better than ours with the true dual-outs, or not

things that make ya go hmmmm

and yeah too funny on the '8s lack of crimps and smooshes - I think (my eye) the diam’s are likely same, bit of optical illusion with smoother bends and no oh I dunno… FLATSPOTS (wtf facepalm FTMFL)

#15

One more thing to point out us I think the s6 generally had 19x9 wheels although technically optional but everyone got them. The s8 is I believe 20x9, which may been optional only last few years of the s6? My real question is how much tire can you fit there without rubbing or rolling fenders, between the two cars?

#16

Lots of good info CountVohn!

The S8 exhaust does look like it would flow better. Less kinks, smoother bends, and dual outlets from the mufflers.

vgvt, according to Tire Rack the S6 came with 265/35/19 tires and the S8 came with 265/35/20 tires. They are the same width but the S8 uses tires that are like an inch taller. With either car I would keep the same tire width as stock but go to 18 inch wheels with tires that have more sidewall percentage. 265 millimeters is wide enough to keep the spinning off the line to a minimum. But these big and heavy cars would really benefit from lighter wheels/tires just like lighter brake rotors.

#17

Agreed! I went with 275/35/19 because that was the only comp size that would work on the wheel. It was actually only like .2-.3 wider than the 265 tho.

#18

Looking back I wish I had gone light weight 19x9.5 with 275 all aroun. Perhaps 19x9 like you suggested would be ideal tho.

#19

I’m not sure if we’re doing mechanical only, or if cosmetics and creature comfort are within the scope of this topic, but, this convo could be a Google result for “differences between the S8 and the S6”.

So how about room in the back seat for long legs and big feet? The A8/S8 is serious. That’s noticeable for us taller passengers.

Also, regarding cosmetics, and I can’t remember specifics, but I remember hearing somewhere that the VW/Audi interiors cascade down from debuting on the upper end Audis, and then appear a few years later in the lower end Audis, and then finally appear in the VW’s. Does the A8/S8 get the newest generation interior before the A6/S6?

#20

Looked this up awhile ago, an you’ll be suprised it’s not extremely more spacious then the s6. Second row leg room is over 1.5 inches more, s6 has a touch more head room vs. S8. But the biggest thing that actually grinds my about the s8 is the trunk is smaller and not quite as wide. Could fit golf clubs much easier in s6.

No one has mentioned this but th steering setups look different servo in the s6 vs. Pwr rack and pinion in the s8. Not sure how accurate the rest of this link is though.

http://www.thecarconnection.com/car-compare-results/audi_s6_2007-vs-audi_s8_2007