Difference between A6 and S4 engines?

[Pgr1990]

I've searched and can't seem to find a definitive answer. The s4 is rated by Audi at 333hp and the A6 310hp. Obviously the A6 is detuned from the factory, but my question is are their any other differences Audi made to the engine besides the conservative software? I ask this because even with an APR tune the A6 still puts out lower numbers than the S4. That makes me think that for some reason the A6's engine may have less performance oriented parts and made of lesser materials. Like the wrx and the sti both have 2.5 liter engines (not sure if they are the same motors) but the wrx has a shittier transmission and the engine is made of weaker components. Is this the same case for the A6 and S4? Someone please enlighten me.

[Kano]

I've searched and can't seem to find a definitive answer. The s4 is rated by Audi at 333hp and the A6 310hp. Obviously the A6 is detuned from the factory, but my question is are their any other differences Audi made to the engine besides the conservative software? I ask this because even with an APR tune the A6 still puts out lower numbers than the S4. That makes me think that for some reason the A6's engine may have less performance oriented parts and made of lesser materials. Like the wrx and the sti both have 2.5 liter engines (not sure if they are the same motors) but the wrx has a shittier transmission and the engine is made of weaker components. Is this the same case for the A6 and S4? Someone please enlighten me.

I doubt that they are different other than software. It seems to me that it would cost more to have two almost identical engines instead of dropping the exact same one in both cars.

[NWS4Guy]

I doubt that they are different other than software. It seems to me that it would cost more to have two almost identical engines instead of dropping the exact same one in both cars.

Zero difference, Ynnekdude has an A6 with the tune. APR took one in house to be sure the S4 tune would work on it, and all fit with no problems. The Supercharged V6T 3.0 we have is very widely used:
Porsche Panamara S Hybrid
VW Toureg Hybrid
Audi Q7 Hybrid
Audi S5 Cabrio (and all versions starting in 2012)
Audi A4 (in Europe starting 2012)
Audi S4
Audi A7
Audi A6

[Kano]

Zero difference, Ynnekdude has an A6 with the tune. APR took one in house to be sure the S4 tune would work on it, and all fit with no problems. The Supercharged V6T 3.0 we have is very widely used:
Porsche Panamara S Hybrid
VW Toureg Hybrid
Audi Q7 Hybrid
Audi S5 Cabrio (and all versions starting in 2012)
Audi A4 (in Europe starting 2012)
Audi S4
Audi A7
Audi A6

Wait, the A4 in europe is getting this engine? What is the S4 in europe getting?

[UmIsThisThingOn]

Wait, the A4 in europe is getting this engine? What is the S4 in europe getting?

Same engine. It's simply an option for the A4, like transmission.

[NWS4Guy]

Same engine. It's simply an option for the A4, like transmission.

Yep, just like the A7 and A6, it will be a massively detuned version. Sad but true, that they can get an A4 S-line (for sport suspension) and chip it and have basically an S4 without ADS or Sport Diff for much cheaper.

[Skyler@Achtuning]

I've been told the S4 and A6 have different cams though I have not researched it. Someone with an up to date ETKA may be able to check if this is true.

[Vogz]

I've searched and can't seem to find a definitive answer. The s4 is rated by Audi at 333hp and the A6 310hp. Obviously the A6 is detuned from the factory, but my question is are their any other differences Audi made to the engine besides the conservative software? I ask this because even with an APR tune the A6 still puts out lower numbers than the S4. That makes me think that for some reason the A6's engine may have less performance oriented parts and made of lesser materials. Like the wrx and the sti both have 2.5 liter engines (not sure if they are the same motors) but the wrx has a shittier transmission and the engine is made of weaker components. Is this the same case for the A6 and S4? Someone please enlighten me.

Strength of components would have zero to do with power output with a tune. The A6 has more restrictive intake and exhaust and that is probably where the power difference comes from when both are "tuned".

I doubt Audi actually runs different cam profiles since most of today's engines can change cam timing a decent amount on the fly. It would only cost them more money.

[Ynnekdude]

I believe the A6 has a more restrictive exhaust and intake, that's it. However, the tiptronic transmission has far more drivetrain loss than S-tronic and 6MT.

A6's are still faster though

C7 A6's are pretty damn quick though. Running 13.4 in the 1/4 stock... C6 did it in 13.9 I believe.

[Dr GP]

Wait, the A4 in europe is getting this engine? What is the S4 in europe getting?

I understand that it will NOT have the same HP/TQ rating in the A4. But a tune could fix that.

[GearHead7]

Can an A6 3.0T or the 3.0T in any model fit into the S4? As long as it has the power steering and from the same gen? I need a motor and anything S4 is double in price compared to the 3.0T found in the same year but in an A6?

[fastboatster]

Can an A6 3.0T or the 3.0T in any model fit into the S4? As long as it has the power steering and from the same gen? I need a motor and anything S4 is double in price compared to the 3.0T found in the same year but in an A6?

I think you don't need it to have powersteering, as some people said somewhere else, it will still have a mount for powersteering pump bracket so you can transfer your pump to the new motor. You might have to swap the wiring harnesses because zf 8 on a6/q5/q7 and dl501 on s4/s5 have different connector pinouts. Might get away repining that connector. Take this with a grain of salt since I haven't done this myself, I went the easy route and swapped 2010 s4 3.0t for 2010 s4 3.0t, but I think somebody posted they had q7 3.0t swapped in and quite a few people replaced b8 engines with powersteering with b8.5 which don't come with powersteering pumps

[Herakei]

Which parts of the intake and exhaust are more restrictive in the A6s?

I have one, in south America, with stronic (thanks god!), I added a KN filter, made a few holes to oem intake box, and I removed cats and will do a 2.5 custom exhaust, Im wondering if there could be some restrictions yet, maybe headers?

[Lalalalala]

Which parts of the intake and exhaust are more restrictive in the A6s?

I have one, in south America, with stronic (thanks god!), I added a KN filter, made a few holes to oem intake box, and I removed cats and will do a 2.5 custom exhaust, Im wondering if there could be some restrictions yet, maybe headers?

Do you have any other mods, stock tune/pulleys?

[Armygsx]

There is differences in the 3.0ts.
Many differences...

The A6/A7 3.0t had different cams then the S4

The 10-12 3.0T is different then the 13+ 3.0t out of the S4/S5

The 13 3.0t is different then the 14+ 3.0t

As emissions get more restricted Audi made minor changes in the 3.0t many times.

I replaced my 13 S4 3.0t and taked to many euro shops when I was shopping around and did a ton of research. Ended up having to find a 13 specific 3.0t to be sure it worked as intended.

Sent from my SM-G988U using Audizine Forum mobile app

[fastboatster]

many of those changes might be supersessions. For example, Audi states that cyl 1-3 exh and intake camshafts are identical p/n for 2012+ A6 and B8.5 S4, or SQ5 or Q7:
https://parts.audiusa.com/p/Audi__Q5...E109102BF.html
https://parts.audiusa.com/p/Audi__A6...E109101BG.html
anyways, I have heard people swapping b8 for b8.5 so they are definitely interchangeable, my guess A6 should work too. most of the difference probably in the software and maybe exhaust manifolds, cats and possibly pcv. Worth trying if on a budget imo

[Armygsx]

many of those changes might be supersessions. For example, Audi states that cyl 1-3 exh and intake camshafts are identical p/n for 2012+ A6 and B8.5 S4, or SQ5 or Q7:
https://parts.audiusa.com/p/Audi__Q5...E109102BF.html
https://parts.audiusa.com/p/Audi__A6...E109101BG.html
anyways, I have heard people swapping b8 for b8.5 so they are definitely interchangeable, my guess A6 should work too. most of the difference probably in the software and maybe exhaust manifolds, cats and possibly pcv. Worth trying if on a budget imo

Neither of those links show it for a S4...
I find that odd that it lists the S5 but not the S4.

I just know I didn't want to run into any issues so I had to find the needle in a haystack 13 S4 engine for my 13 S4.

Nvm, after adding a 13 S4 to the garage it shows it fits... perhaps there is no difference after all.. sucks considering a used A6 3.0t engine costs less then a S4 engine lol

Sent from my SM-G988U using Audizine Forum mobile app

[wootwoot]

The 2016-2018 A6 put in a number of changes to the engine, engine code CREC. Dual injection, improved intercoolers within the supercharger, and more stock hp at 333. That's not a full list of changes but some of the big ones.

[Smac770]

It's easier to dissect differences when talking about two specific engines, identified by engine code, vehicle model, and vehicle model year. Looking at the US 3.0T, there's 7 different engine codes [CCA, CCB, CGX, CTU, CJW, CTW, CRE] across 11 different model bases [C6.5 A6, C7.0 A6/A7, C7.5 A6/A7, D4.0 A8, D4.5 A8, B8.0 S4/S5, B8.5 S4/S5, B8.5 Q5, B8.5 SQ5, E1.5 Q7, E1.5 Q7 S-line].

I've already posted a chart I made of the different 3.0Ts in the US market models, https://www.audizine.com/forum/showt...1#post14320929
You can see the first response, "I replaced my B8.0 S4 CAKA (so probably EU market) with the Q7 CJT". But he doesn't elaborate which CJT (only one is 333hp), and still comments "plug and play, well, except this and that". The this and that is important.

I assume the particulars of swapping the engines native to the B8 S4, [CCBA, CGXC, CTUB], is already known. Similar to "sure, you can move that 2013 CAEB in place of your 2010 CAEB, so long as you move your old 2-pin crank position sensor over". So even when it's the same engine code in the same model, there can be little details that have to be known.

When Audi added dual injection to the EA888 2.0T for EU emissions changes, the US versions do not include them. The CRE has the same port injection addition for EU emissions; did the CREC in the US A8/A6/A7/A8 retain the dual injection system? I imagine even if you added all the wiring, the S4 ECU wouldn't know what to do with a CREC engine.

[Blownmotor]

Sorry about the thread revival.
Just letting everyone know you can put a 09-11 A6 engine in a 2012 S4. The block needs to be modified around the starter, and the ecu needs a full reset before it will run without the EPC light. The motor I found had VIN 5th digit "G", same as my S. The lower costs was definitely offset by the custom work, but getting my car back after a month of down time was worth it.
Use the S4 peripherals to make it as smooth as possible.

[xezo]

By any chance, anyone knows if there's any difference in pistons. I'm looking for CAKA pistons (s4 b8 2010) and only found CGXC pistons ( s5 2013 ). Will I be able to fit them in ?

[dalmation53]

Thread revival again. I'm looking for an engine my car is a 2013 A6 3.0T. And found a great price engine from an S4 at $3k can i make this work?

Sent from my SM-G990U using Audizine Forum mobile app

[Smac770]

If it's a CGX or CTU, should be fine. The tune level is set by the ECM (ie, 310PS CGXB vs 333PS CGXC). The headers are vehicle specific, so you'll reuse those. If it's a B8.0 CCBA, you'll have more parts swapping to do (get rid of power steering pump, PCV vacuum level, etc). But general idea from recent threads seems to be it should be doable with some effort.