[PlatzdaTurbo]

Originally Posted by suhaas307

Tell me something I don't know, PT.

I'm completely aware of the fact that they're in a different state of tune. It's as obvious as it can be. I also knew they were similar. But that's just the block we are talking about. The entire engine can never be identical. There will be minor differences. And I'm completely aware of how technology takes forward 'the car'.

Now when someone says two engines (the A6's and the S4's) are identical, it can't be true. Sure the block is the same, but c'mon. There are so many differences, like how the power is put down on to the road.

There is no denying that VAG share engines. It's a common fact.

I hope you understand what I was trying to convey.

Well it did seem as if you 'didnt know' pal !

'Now when someone says two engines (the A6's and the S4's) are identical, it can't be true.' - This is your statement from the above post.

Harbir seemed to claim the exact above statement in one of his earlier posts when we were talking about it in response to which you come in and retort with "are you sure?"

Well i dont know about him but i AM sure is why i posted.
What i have posted in my previous post is fairly obvious and straight forward but seemed to me initially that you were unsure even about all those facts.

Hence the basic post , Mr. Mod !

Look on the bright side, atleast now you are sure about what you know

[Harbir]

look, whether the engines are identical or not, the performance difference between the A6 3.0T and the S4 is too small to set the S4 apart as being of a meaningfully higher performance level.

I expect the S4 to set itself apart from the A6 3.0T in the corners. In the speed department, I expect it to have no more charisma, and little more go than the A6 3.0T.

[PlatzdaTurbo]

Originally Posted by suhaas307

Now when someone says two engines (the A6's and the S4's) are identical, it can't be true. Sure the block is the same, but c'mon. There are so many differences, like how the power is put down on to the road.

I hope you understand what I was trying to convey.

I'm sorry but i really dont & i would love it if you explained the above in further detail.
First of all let me get 1 thing out of the way - Harbir & myself were only debating on whether the engines are in a different state of tune in both cars or is it a marketing gimmick by Audi.
Where i feel the engine is indeed tuned slightly higher in the S4 vis a vis the A6, Harbir feels it isnt and either of us could be wrong ,there is absolutely no denying that.

Now you say, when someone says two engines are identical it cant be true.
Query - Why ever not ?
Fiat's famed multijet is shared not only across variants but companies right from Tata to Maruti to Fiat themselves the mark-able difference being that the engines with higher power and torque come with a VGT.
Considering that, why cant the identical engine be shared between 2 variants of the same manufacturer ?
The A6 3.0T is the top end petrol variant this side of the S & RS models hence it is supercharged and the S4 is the half-way sporty version of the A4 and the quickest A4 after the RS4 avant and hence it too has a supercharged block.
The power is transferred to the road in both cars in an identical manner so unless you are going down to the smallest cog , i dont see the difference.
I love Audis and read a fair bit about them and still feel there is a lot to know so if you can tell me even 1 of the 'so many differences' that you feel could be there in the engine (A6 vis a vis S4) please go ahead.
Would love to know

[Akshay1234]

Originally Posted by Harbir

EDIT: I just found out that the A8 will be offered in the US in 2013 with the 3.0T, rated at 333hp. So there it atleast one non S model that will be carrying an engine identical in spec to an S model. If there are differences, such as boost levels or breathing efficiency, it should be easy to find references on the internet. Its like the 525D and 530D. These cars have IDENTICAL engines, except for the ECU programming in the 525D restricts boost and fueling to keep the performance lower than the 530D. Or the two variants of the A6 3.0TDI. One is rated 245ps, the other is rated 313ps. The differences in these engines are easy to find on the internet.

The A8 is already offered in a couple of places with the 3.0T and I've seen one in Bombay too. The 525 and 530D used to have the same engines, but now the 525 shares the engine with the 520d + another turbo. The A6 3.0tdi which is 313ps is twin turbo compared to the 245ps which has only one turbo.

There is a 300lb difference in the curb weights of the S4 and A6 3.0t, but you may be right. I think the engine tune is the same in both with Audi underrating it for the A6. As for the A4 3.0t it must be restricted to 270bhp.

[suhaas307]

Originally Posted by PlatzdaTurbo

I'm sorry but i really dont & i would love it if you explained the above in further detail.
First of all let me get 1 thing out of the way - Harbir & myself were only debating on whether the engines are in a different state of tune in both cars or is it a marketing gimmick by Audi.
Where i feel the engine is indeed tuned slightly higher in the S4 vis a vis the A6, Harbir feels it isnt and either of us could be wrong ,there is absolutely no denying that.

Relax, it's just a discussion.

By saying, "are you sure?" I was trying to say that two engines can never be the same due to the different applications. Because they are mated to different transmissions and of course, as you'd mentioned, tuned differently. The S4 for example sounds different courtesy a different exhaust. It's quite possible that there are some other components that are different too.

Habir does have a point. Quoting the performance figures reveals a lot. It looks like there is only a marginal difference between the A6 and the S4 and that could be attributed to the lighter kerb-weight and different gearing. Now he says that if the S4's engine is in a higher state of tune, it should show up in the performance figures. But it doesn't. The marginal improvement in performance could be due to the lesser weight of the S4.

I do believe that the S4's engine is in a higher state of tune. But how can it be proved? That, I'm not sure.

[maxbhp]

Originally Posted by Harbir

This is the same engine in my dad's A6 3.0T quattro. It is in fact 333hp in all of its applications, but Audi is quoting ratings from 295 to 333 for various applications depending on its marketing needs, even though in all cases the engines are identical.

Same engines at various state of tune with minor changes in components to take the added change in the permissible factor of safety while running. This is not started in India by Audi but by the Mercs when they started CDI engines in India.

[i<3turbo]

ok i havent read all of the thread but from what i have read im getting a headache. i have a 2012 s4 here in the US. when i come back i will buy another s4 soo glad AUdi india has launched it. The S4 makes more hp then 333 and more tq. it is under rated from the factory for insurance purposes. many people dyno their S4's anywhere from 310-325 whp stock. dynos usually measure their fly wheel hp around 370-380hp.


the s4 does 0-60 in 4.4 in the s tronic version and 0-60 in 4.6 with the manual version. i have connected a vbox to my car and i have done 4.5 launching the car hard spinning all 4 tires with the asr completely turned off. (i have a manual)

the s4 is such a good buy. i will gaurantee this because for the price it beats alot of cars in the 1/4 mile and 0-60.

we have a closed road here near my house which is almost 2 miles long.
I have raced my friends B7 previous gen RS4, M3's e46's and believe it or not, even the new e92's and e90's, W210 E55 amg's, and a xfr and i have beaten these in the 1/4 mile mark.

The e9x m3, xfr, rs4, catches up and passes me around 120 mph but the s4 still gives it a good fight.

at the end of the day the s4 is a really good buy especially for the price.
i love it and im soo happy i stumbled across this thread because i know there will be a s4 waiting for me when i get back to india

My intake comes in today for it gonna install that and then get aftermarket pulleys for the s/c and a tune and i should be anywhere from 470-490 hp!!! cant wait

[i<3turbo]

So just a quick update...i dynoed my car stock and i made 317 whp and 308 wtq installed the intake and made 336 whp 329 wtq.

[Harbir]

Audi and BMW are both suspected of underrating their 3.0 forced induction engines. Assuming about a loss in the transmission, driveline and tyres of 20% (its typically 18-20%), 317whp would translate to 396hp at the crankshaft.

But my issue is not max horsepower. It is whether the 3.0SC in the S4 is ~40hp more powerful than the 3.0SC in the A6. The performance measured by Car and Driver of the S4 (manual transmission) and A6 3.0T (slushbox, not DSG), does not show the sort of difference you would expect to see between a 295hp car and a 395hp car. The difference we see is in fact about what we would see given their weight difference and the fact that a conventional torque converter automatic without launch control will always be slower than a 3 pedal manual in acceleration tests.

My contention is simply that the engine in the A6 3.0T is in fact not 40hp down compared to the same engine installed in the S4. Whether they are both 333 hp or something else is not something I am particularly concerned with.

[i<3turbo]

The a6 3.0t in the us comes with 325hp and 318 tq measured to the flywheel as audi listed it. I guess the indian a6's are detuned. Ill find you a link where i think car and driver called audi and bmw out on the s4 and the 335 on how it was under rated

[Harbir]

the A6 3.0T is rated variously at 295, 299, 310, and 325hp. the car tested by car and driver with the non-DSG auto was rated at 310hp. Firstly, I doubt very much that Audi is selling 4 different tunes of the same engine in the same car different market places. Secondly, if the S4 really has so much more power than that, and is lighter, and the test unit had a manual transmission vs the tested A6 which had a non-launch controlled conventional torque converter automatic, then it should have been much quicker in C/D testing than it was.

I have seen absolutely nothing except audi official claims showing that the A6 3.0T and S4 are powered by differently tuned engines. And since the audi official claims on this engine are known to be not accurate, who knows what the heck is really going on.

[i<3turbo]

i understand what your saying but ill try and find you the link where i think it was either car and driver or road & track that said that the s4 and bmw 335 were under rated. I actually ran my buddies A6 3.0T with the s-tronic and beat him pretty bad prolly by 3-4 cars from a 40 mph roll.

[Harbir]

Was this in the US? As far as I know, the current A6 has not been offered in the US with the DCT, only the torque converter automatic.

The performance figures for that and the manual Trans S4 as tested by C/D have been posted to this thread.

[i<3turbo]

Originally Posted by Harbir

Was this in the US? As far as I know, the current A6 has not been offered in the US with the DCT, only the torque converter automatic.

The performance figures for that and the manual Trans S4 as tested by C/D have been posted to this thread.

Yea this was in the us and it has s tronic pretty sure because on a recent roadtrip we were at 80 mph in 7th gear crusing. The triptronic only has 6.


To prove my other point
http://i.autoblog.com/2009/10/28/rep...is-underrated/

[Akshay1234]

Originally Posted by i<3turbo

Yea this was in the us and it has s tronic pretty sure because on a recent roadtrip we were at 80 mph in 7th gear crusing. The triptronic only has 6.


To prove my other point
REPORT: Evidence mounting that 2010 Audi S4 is underrated - Autoblog

No the normal auto is an 8 speed if I'm not mistaken. So 7th was possible.