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Hi All.

I have an 03 S4 avant B6 and am looking at one of two options:

1. Buy new RS4 avant (in 1 year)

2. Look to upgrade the S4 power-wise through 'approved' mods to CHIP and ECU etc.

I have read a few posts about the AMD conversions and seeing the power and torque increases, realised I am not a petrolhead and need a plain English version as to what they actually mean to performance handling etc of the Avant.

So my main aim - get a bit more grunt out the beast to get the most out the lower revs and give it better top end pull for overtaking and seat of pants driving on quiet roads etc....!

Given the jump in the new RS4 price to about £50k - wondering whether I take the £30k trade in I would probably just about get and put another £20k against a new car or just spend £10k buying my way to a similarly powered S4 without the wait but with all the fun?

So any views from experienced members on what actual happens and how that affects everything would be very much appreciated. Plus is it necessarily AMD to go for?

Cheers in advance
TinkyWinky

I can give you 'armchair' advice as follows:

The torque graphs shown on the AmD website are rather useful, although it is a shame they don't have a stock graph as well.

For your £1K the stage 1 remap will not be a 'step-change' in performance. You should be able to feel the extra mid-range torque and top end power, and the engine ought to feel smoother, but you are not going to be stunned.

I would still say the same for the £1500 stage 2 tune, and indeed the difference between stage 1 and 2 for £500 is relatively negligible.

The stage 3 tune however is a step-change in performance. If you go from stock to stage 3 then you will notice the difference. You will feel the car pulling harder throughout the rev range, and indeed it should be smoother. I also expect it to be quite louder too. Of course this does cost £3200!

Now regarding the RS4, I'm not sure what Audi have done to the engine. The quoted peaks of 430 Nm at 5500 and 420 PS at 7800 are obviously higher than your S4's 410 Nm at 3500 and 344 PS at 7000. But most significant is that on the RS4 at least 90% of peak torque is produced between 2250 and 7600 rpm. This means that whereas your car is producing around 350Nm at 7000, and an AmD stage 3 will be about 390Nm (and both falling rapidly), the RS4 will have at least 387Nm and falling slowly because it has 387Nm at 7600, about 380Nm at 7800 and probably still around 330-350Nm at the 8250 redline.

What this means is that undoubtedly Audi have done serious tuning to the S4 V8 for the RS4. What I expect is that the engine performs similarly to an AmD stage 1 up to about 6500 rpm, but then as the S4 torque tails off, the RS4 will be pulling very strong to the redline.

Coupled with the weight reduction and transmission changes (I understand that the RS4 will have a rear bias), this will make the RS4 one hell of a racing car.

I guess the AmD stage 3 S4 will still produce more mid-range torque than the RS4, but the weight difference will cancel that out on the road. Then of course there will still be 'some' tuning potential on the RS4 because I have no doubt that the OEM ECU map will still be conservative and the somewhat exhaust restrictive. Exactly how much more can be got out of it remains to be seen.

So in conclusion you need to decide what you want out of a car, and I suggest you examing how you drive. I believe that for general fast road driving (i.e. mid range accelaration and not much redlining), a stage 3 S4 will be comparable to an RS4. However on full sprints and on the track, the RS4 will show clear superiority.

This is the basis on which I decided not to get a B5 RS4 or a B6 S4. I do not track my car, I do not do many road sprints, and don't go to the redline much. On this basis my 560 Nm peak is quite satisfying in comparison to what the new S4 and RS4 can offer.

(Plus I am in no position to buy an new car anyway!)

Hi Dippy,

Thanks for that - exactly what I was really looking for - sounds like diving in for the Stage 3 will provide the additional punch at lower revs and through the range, although will fall short at the final hurdle.

So, as I am not a track driver ( i think if I was going to do that I would get a Cooper S Mod to be honest! ) I am unlikely to require the RS4 and it's capabilities. Especially given the £20k I would have to put down.

I assume I can straight for the stage 3?

TW

Yes you can. AMD do many S4's before the wrapping is off them so the dealer delivers them already done.

Here's the graphs for my car showing stock and stage 3.




If you want to look at them full size then go HERE and click on the image once to bring up a small image, and again for the high res one. Unfortunately that site doesn't let me link directly to large ones.

The figures :
Stock
Standard at 6383rpm was 337Bhp/251KW/342PS
Standard at 3259rpm was 324lb-ft/440Nm

Stage 3
Peak at 6639rpm was 395Bhp/295KW/401PS
Peak at 3366rpm was 375lb-ft/509Nm

I wish I could recommend it but at the moment I'm not sure I can or can't! See the "Scotty" thread.[/url]

Dippy wrote:On this basis my 560 Nm peak is quite satisfying in comparison to what the new S4 and RS4 can offer.

Dippy,

Have you got any graphs so I can see how peaky the peak is? I know the B5 S4's tune really well but I'm sure if they're really laggy or quite flat.

Curious......whats the cost of the AMD stage 3?
Cheers fc

From the site http://www.auto-amd.com/s442v8.asp

Works out at £2750+VAT

I think that's right anyhow. Pretty good value if it works as it says it does.

Frank, it's £2750 + VAT for the AmD Stage 3

AmD Website

I am thinking about this exactly as I was waiting for the new RS4 myself but don't like the look of the power curve (I don' t want to rev it to death all the time) or the price. What does AMD do to warranty, longevity of gearbox, clutch etc and do AMD have agents' around the country approved to do it.

PS An 03 S4 Avant would only trade for about £25k. I just bought my 2nd one, an 04 with <5k miles and a £43k spec. It was £10k+ cheaper than list, bought from a main dealer. Gives me lots of cash for the AMD. Just a shame I paid full price for a new 03 one two years ago!

Well if only £25k trade in then this is defo my route - much rather get a new Golf Gti to run round town in (and get more than 13 mpg too )

Is AMD the only real tweaker out there? I haven't seen many others mentioned apart from MTM (is that right - saw an s3 with tuning) or QST?

That's exactly what I think. If it was limited run (the RS4) I'd have one but to pay £32k* to change, why?, when you could AMD your car for a tenth of that.

*Trade value of an 03 S4 Avant in spring 06 probably £22k, retail of an RS4 Avant with £3k of extras about £54k.

God these things are going to depreciate

Scotty,

My graphs are only in paper form (I must get around to scanning them sometime). However there are plots of a stage 1 2.7T on AmD's site. Mine has the same profile exept is much flatter in the main band (2500 to 4500) and does not have as much 'noise' (I don't know what AmD couldn't have done a better plot). Also it is about 30 lbft higher up the scale and does not tail off anywhere near as much at the top-end (as a result of my full Miltek system).

It's interesting to see your torque plot. I'll have a better compare with mine tonight, but I can readily comment as follows:
1) Yours seems to have lag too. Whilst I imagine you have more torque below 2000 rpm (as yours is still a 4.2 V8 where mine is just a low-compression 2.7 V6), at 2000 rpm we have similar torque, but at about 2500 rpm I have close to my peak torque (the 'brow' of the hill) whereas yours seems to come in nearer 3000 rpm.
2) Your 90% of peak torque apprears to be around 2500-5000 rpm which is roughly the same as mine (I'll check), except that my peak is about 10% higher.
3) Your top end is similar to mine up to about 6000 rpm where my power levels off (but at least does not fall off like S4s with OEM cats) whereas yours has that additional peak (my redline is about 7250 rpm - where is yours?)

You can draw your own conclusions from this!

Also I am happy that my 'armchair' calculations above appear true: The RS4 will act like a stage 1 S4 up to about 7000 rpm (apart from the weight reduction and transmission changes of course), but then the changes really kick in.

If B6 S4s are trading for £25K then what would mine fetch? I think I will be keeping my car for a while yet and so I expect it will have K04 turbos sometime in the future...

Dippy / Scotty, would you be recommending the AMD then? I think you have both put good and bad sides as to the effects of the mods you've had.

Can I be bold and ask for a recommendation, a wait and see or a no way go elsewhere sort of angle on the AMD Stage 3.

I see no one else has made any suggestions on another tuning company - so I guess AmD are the fellas!?

Cheers
TW

I visited AmD for some "hardware" mods - namely a Milltek cat-back (didn't opt for downpipe and cats) plus a Hyperflow induction kit...

This produced "similar" figures to ScoTTy's (without the AmD chip). I think his torque was up on mine, but it was as "stock" too, I believe...

APR (and Superchips...) also have maps available for the B6 S4 lump. I'm particularly interested in APR, as you can have several programmes (eg Optimax, Stock, Valet) installed at the same time, switchable using the Cruise Control stalk. If you don't have cruise, you can get it retrofitted for about £200.

Furthermore, APR do a 6 hour trial as the map is uploadable via ODBII and isn't a physical chip install...

Once I get my car back from the dealer (in for pulley work and throttle software update) I will be getting a 6hr APR trial, complete with before and after RR runs at an independent garage.

This should give a fair comparison, and enable me to decide whether to fork out the dosh they want for it.

If I am happy with the results, I may be able to twist their arm for some sort of "Group Buy"...

BTW, I'd be looking at getting the trial "mid April" due to time constraints at the moment...

Whilst AmD did appear to be the only UK tuner of the S4 lump (MTM don't map it, AFAIK) - that definately isn't the case. There are other options, its just they are largely untried. I probably have the only Hyperflow fitted to a UK B6 S4