2004 audi s4 real max power ?

adamss24

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As per title, just bought a tidy 2004 s4 saloon which is in need of some love and i am wondering what are the max power gains that can be had from the v8 NA engine ? It's missing a few bits: front centre armrest, had RNS E at some point but has been removed and it looks like it's been mapped at some point- the engine is rather loud with the factory exhaust ! Good thing is a manual and with a few cosmetic tweaks it can be made a looker ! I wasn't in the market for a powerful v8 saloon- an estate would fit my bills a bit better but i will give it a try for a little while ! The engine is healthy and is quite low mileage, will post a few pictures when i get it back home from it's previous owner !
 
I will give it a try for a short while, it's supposed to be mapped to about 380Bhp and it's not bad overall ! It will have a hard time bettering the a6 on a motorway drive, that a6 is an animal, pushed it to speeds over 140Mph and still averaged 45Mph on m1 ! Collecting the s4 this weekend, could not be ***** to tow it today- just went to see it and then bought it !
 
it all depends on what you do to it as to the gains

normally aspirated and tuned well they are capable of in excess of 400bhp supercharge it and you are closer to 525bhp on a stage 1 map with stage 2 still in devolpment and looking at nearer 600bhp .... unfortunatly the clutch wont last 2 minutes at this kinda power unless you have the tiptronic version in which case its close its near its limit but capable of holding its own as its the same as an rs6

standard exhaust with a re-map will be around 350-360 if its a very good map if its a cheap one closer to the bottom figure

the standard exhaust is very restrictive indeed this should be the first thing replaced if your after more performance
milltek cat backs work very well , but the biggest improvement is from removing the pre cats .... be aware of two differant version
resonated and non resonated
resonated has an extra silencer which quietens the exhaust down , but its still loud and growls
non resonated has no silencer and is very loud all the time , but drones badly at motorway speeds

air filters do not work on the car , so leave the standard one well alone
 
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Thanks for suggestions, i do know a thing or two about tuning and this won't go too far to be honest, i reckon 380 Bhp is plenty fast enough for day to day drive and going fast cost money ! As per clutches i do have now 700 Nm of torque running trough a stock 01E gearbox and Sachs SRE/Loba rs4 clutch and it holds pretty nicely- a little shudder on take off but easy to live from day to day... I think the stock Getrag manual gearbox will hold better than any auto gearbox- i am not launching any of my cars from traffic lights or take them at Santa Pod ! Matter of fact i have a b5 rs4 clutch specified to go over 550Bhp on one of my other cars, i could use that with a custom SMF and i'm sure it will hold whatever that engine can muster.
 
the gearbox isnt the problem , its the clutch which cannot handle it unfortunatly they are weak on the manuals
as said the clutches in the auto or tip gearbox are fine but on there limit , but the one in the manual will not last two minutes
and is usually replaced if going down the supercharged route
 
it all depends on what you do to it as to the gains

normally aspirated and tuned well they are capable of in excess of 400bhp supercharge it and you are closer to 525bhp on a stage 1 map with stage 2 still in devolpment and looking at nearer 600bhp .... unfortunatly the clutch wont last 2 minutes at this kinda power unless you have the tiptronic version in which case its close its near its limit but capable of holding its own as its the same as an rs6

standard exhaust with a re-map will be around 350-360 if its a very good map if its a cheap one closer to the bottom figure

Really? The JHM supercharger stage 1 is only about 420bhp. They say any more than that and the rods bend. As much as I love the S4 and miss mine I think your figures are a bit on the high side.
 
Yes really

What i have quoted is power at the crank the same as the manufacturer quotes
There are several you tube videos showing cars making in excess of 421 hp at the wheels
On a dyno
When you account for 25% transmission loss (typical loss for a 4 wheel drive system )
This equates to 526.5 at the crank
So my figures are spot on i
Hope this explains the differance between crank horseppwer and wheel horsepower
 
Yes I understand the differences between crank, wheel HP and transmission loss I just don't believe that a tuner would be able to get 400 bhp on the crank with just a tune alone. Maybe on a turbo car but not NA
 
A good map with pre cats removed, high flow cats (or complete decat) plus a kilter system should make at least 370bhp at the crank usually more, probably not over 390 though.
 
A good map with pre cats removed, high flow cats (or complete decat) plus a kilter system should make at least 370bhp at the crank usually more, probably not over 390 though.
That's what mine has at the moment: milltek decat pipes, cone filter (will be removed asap) and a remap...did not driven the car yet as it still needs some work !
 
Congrats on your S4 purchase, pics to follow soon we hope.
 
Yes I understand the differences between crank, wheel HP and transmission loss I just don't believe that a tuner would be able to get 400 bhp on the crank with just a tune alone. Maybe on a turbo car but not NA

i never said with just a tune they would go over 400 i said it depends what you do to them as to what gains are achieved
with just a re-map chip then no , but with the pre cats gutted or de cats and a decent exhaust plus a few other bits then yes over 400bhp is achieveable
and is being done on a daily basis by companies like jhm

replacing the air filter system on a b6 or b7 s4 is a waste of time
 

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