4.0 TFSI - S6/S7 vs S8 - Dyno Comparison

A6 All/ S6 All
#1

The 4.0 TFSI is a pretty awesome motor. From the OEM, there are a couple different configurations and different outputs depending on model. Here’s what the factory rates them at in Metric HP (PS) and lb-ft of Torque:

S6/S7
Horsepower (@ rpm) - 420 @ 5,500-6,400
Torque (lb-ft @ rpm) - 406 @ 1,400-5,200

A8
Horsepower (@ rpm) - 420 @ 5,000
Torque (lb-ft @ rpm) - 444 @ 1,500

S8
Horsepower (@ rpm) - 520 @ 6,000
Torque (lb-ft @ rpm) - 481 @ 5,500

RS6/RS7
Horsepower (@ rpm) - 560 @ 5,700-6,600
Torque (lb-ft @ rpm) - 516 @ 1,750-5,500

Depending on model they have different transmissions too. The S6/S7 gets the DSG while the A8/S8/RS6/RS7 all get a tiptronic.

We strapped our S7 and S8 to our Dynapack All wheel hub dyno and got some pretty interesting results out of the motors both stock and modified. The figures were were putting down to the hubs was very close to what Audi rated the vehicles at the crank. We’re wondering if Audi downplayed the output of these engines. We went ahead and figured a drivetrain loss that seemed reasonable for our marketing figures, but the results were higher than what Audi stated.

Here’s some interesting data at the wheels:

NOTE - Due to image size, you’ll need to scroll right to see the HP graphs

S7 vs S8, 93 octane, all 4 wheels, stock:

http://www.goapr.com/includes/img/products/dyno/40tfsi_d4_s8/s8-oem-93-vs-s7-oem-93.png

Next up we compared the S7 with APR software to the S8, stock with 93 octane

http://www.goapr.com/includes/img/products/dyno/40tfsi_d4_s8/s8-oem-93-vs-s7-apr-93.png

Now here’s a comparison of the S8 stock and the S8 with APR software on 93 octane

http://www.goapr.com/includes/img/products/dyno/40tfsi_d4_s8/s8-oem-93-vs-s8-apr-93.png

And finally, the S7 with APR software and the S8 with APR software, both on 93 octane

http://www.goapr.com/includes/img/products/dyno/40tfsi_d4_s8/s8-apr-93-vs-s7-apr-93.png

On both cars, the S7 and the S8, there’s room for more torque on 93 octane, but we didn’t want to push it too far on stage 1, so we capped torque around 525 AWFT-LBS of torque and 625 AWFT-LBS of torque respectively. The S8 has all of 700+ AWFT-LBS of torque in it if you go really hard!

Now I don’t have good back to back acceleration data, but here’s what the S8 put down with APR 93 octane stage 1 and with stock software. The gains are pretty impressive and this thing really throws you back in your seat!

http://www.goapr.com/includes/img/products/dyno/40tfsi_d4_s8/40tfsi_d4_s8_s0_vs_s1_93_0-130.png

http://www.goapr.com/news/wp-content/uploads/2013/10/s8acceleration.png

#2

Amazing performance!

I’ll make the 1/4 mile prediction.

11.44@125.2mph in good conditions on 93.

#3

Man, those cars put some power down. Nice to see them wake up with the tuning as well. Love to see them with some opened up exhaust and good fuel.

#4

For the S8, on 100 we just continued to advance ignition at the point where torque was falling. We could get a bunch more in the midrange but we didn’t want to stress the transmission.

What’s awesome is every degree of ignition makes a rather large jump in power.

For the exhaust, maybe I’ll have some data of it uncorked sooner or later. ; )

#5

Full exhaust, race gas, intake and 104 tune this car will break into the 10’s.

#6

It will be interesting to see how the marshals at the strip will deal with these cars, in particular relating to the cage rules. 11.49 and below I believe? There’s no doubt these cars were made to go that fast down the autobahn lol.

Thanks for sharing Arin, great info!

#7

Great stuff! Can’t wait to see some passes in the tuned s8 and even more so the rs7…

Oh and Arin, we really appreciate you sharing this information on AR, I think I can speak for most on the site when I say that…

#8

Awesome.

Looks promising for my soon to be here S6 :slight_smile:

#9

No problem guys!

Heck, I’d almost want to strip the interior, crank up the tune, throw in some 104 and see if we could pull of an insane pass at the strip against some huge muscle car beast. I may have to do the passes in a tux… I could see a pretty epic video coming from such adventure. ; )

#10

That is awesome gains! Holy smokes!

Haha doing passes in a tux would be rad!

#11

Nice! A replacement or an addition?

#12

Trade in. :slight_smile:

University Audi has a Suzuka Grey RS5 that I was tempted to take home. God I wish it had four doors.

#13

What was the stock torque on the s8? Around 480 in one graph and 400 in another. Am I misreading it?

#14

S7 dips down to around 400. S8 dips to 475 after the spike.

#15

First chart s8 is 470ish wtq and 470ish whp
Second chart stock s8 is again 470ish for bot
Third chart, tuned s8 vs stock s8…and now stock s8 drops to 406 wtq.

No?

#16

Nice! Would love to check out the car sometime. Current and new… :slight_smile:

#17

Unless Arin has edited the pictures, what I’m seeing is that the S8 never reads lower than 475wtq and 495whp on any of the charts listed at all. The S7 stock is close to 400wtq in the first one, but that’s the only graph that ever shows a number lower than 450 torque at the wheels.

Kinda a comical thing to think about on cars like this and so big as well. Yea, even stock there’s never a time that it’s not putting at least 400wtq/whp down for the S7 or for the S8 it’s closer to 460wtq/whp lol.

#18

I’m not seeing that. I have the following labels on the charts:


First chart:

S8 - Stock 93 | S8 - Stock 93
S7 - Stock 93 | S7 - Stock 93

Second Chart:

S7 -   APR 93 | S7 -   APR 93
S8 - Stock 93 | S8 - Stock 93

Third Chart:

S8 -   APR 93 | S8 -   APR 93
S8 - Stock 93 | S8 - Stock 93

Fourth Chart:

S8 -   APR 93 | S8 -   APR 93
S7 -   APR 93 | S7 -   APR 93
#19

Arin, you guys planning on an C7 4.0T exhaust?

#20

Testing ‘something’ now to see if it makes a difference.