BASARAB

Has anyone tried both and is there really a difference? Since transmissions and power output are pretty much the same, the only difference I see is firmer suspension in S8

DallasDave

Good question, I am interested to know too.

OberklasseA8

s8 or S8 PLUS??

A8L_New_England

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I guess it depends upon what you mean by "difference".
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OberklasseA8

I've tried both and they are different. If you are trying to make a A8 an S8, it not worth the money to build. Its better to just get an S8.

What is the goal of the "A8" build? Drag racing? If so, you can make an A8 faster then an S8 somehow someway I'm sure.

BASARAB

Not trying to build anything. Just curious if a tuned A8 has the same driving feel as an S8, if it feels like the same exact car when driving around

BASARAB

For example I had a D3 S8 and when I would drive my buddy's D3 W12, they felt like different cars. Different power delivery, different transmission tuning, different suspension feeling over bumps even in the sports mode.
I am sure D4 S8 and D4 W12 also would feel different, but A8 4.0 and S8 just seem too similar, like same exact car

gk1

If you are curious just about engine power I thought the A8 4.0T used the same turbos and was similar in power to an S6/S7 whereas the S8 uses RS7-sized (larger) turbos and there are plenty of comparisons of tuned S6/S7 vs. stock RS7 around.
Just based on engine power I would think the +70FT-LBS of the tuned A8 would be more noticeable than the -30HP unless you kept the revs up in the S8 perhaps.
Stage I D4 A8 4.0T = 545/629
Stage I C7 S6 = 570/630

Stock D4 S8 = 577/556
Stock C7 RS7 = 560/560

BASARAB

Not curious about the engine power, curious about the overall feel of the car

BASARAB

Like I am literally curious if I drive around in a tuned A8 for 15 minutes, then get out, jump in a S8 and drive around for the same amount time on the same roads, if I would feel that I drove a different car