Hi all,

I'm looking to buy an audi s4 and I'd really like some input on the differences between each model year. I've been looking around, and I'd really like to get a B5 s4, but I'm worried that a year (or even two) down the road that I won't be able to find one thats worth keeping.
From a performance standpoint, do you think that the b5 is easier to work with and upgrade versus any of the newer models? What are the major differences between the b5 / b6 / b7? I know about the different engines, but things like reliability (like the biturbo v6 vs the 4.2 v8) and what it takes to build them up are what I'm interested in. I don't know much about audis at all and any feedback you guys have would be great.

Thanks!

 

The B6 and B7 are very similar, the differences between the two are mostly cosmetic. They are generally very reliable but the options for modification are somewhat less than the B5. A remap "chip" + exhaust are the standard for performance. Supercharger kits are being tested and released, a couple people have tried nitrous but no big power-adders are common yet. Theres plenty more you can do for brakes, suspension, weight reduction, etc. In the future as the cars drop in price and younger people buy them demand for performance parts will increase and im sure well see more available.

B5s have been steadily dropping in price over the past few years. Now they range from about $6500 to $15,000 depending on options, miles, and condition. This a cult car and has a sizable enthusiast following, they will always be worth buying, maintaining, and upgrading to their fans. While you can buy one for under $10,000 it is still at $40,000 car to maintain, and they have their fair share of problems, which can be costly to repair. On average people spend over $1000 a year sometimes much much more. As far as modifying goes this car is great, you can go as big as you want. A chip and exhaust can get you a sizable ammount of HP and TQ but you sacrafice reliability on the stock turbos. Stage 3 Turbo kits ranging from 360whp on k04's to 700+whp garretts are available. K04's can go on a stock motor with a few supporting mods, but by around the 500whp mark a built motor becomes very important, people bore and stroke to 3.01L, new valvetrain, bla bla bla. Much more going on with this car than the B6+ B7

 

Wow - thanks for all the info.

Yeah the B5 is the one I'd really like to get, but I'm probably going to get one in at least a year or two, and I'm just worried that by then they'll be 'too old' to be worth really investing the money - or that if I do end up putting money into it, I'd basically be just replacing everything in the car which is something I don't want to do. I guess my question is, do you think that B5 S4's will be 'too old' in a year or two - because I'd really like to keep the car for 5+ years..
So as for engine performance, in the B6/7 there aren't really any 'mainstream' forced induction mods? Are they designed to work with that kind of setup?

 

the forced induction on a b6 or b7 is still kind of in the testing stage. there are kits starting to come out but since they're new to the market they are quite spendy since most parts arent mass produced yet however i have a feeling in the next year or two the b6/b7 modding is going to grow since most b5's are hitting that 100k+ average mark and things are starting to break and wear down. if i could i would trade my b5 in for a b6 mainly just because i like the body style more. if i could get a supercharger as well it would make the change that much more enjoyable

 

I like the B5 way too much to trade it for a newer model, if anything i would want to widebody a B7 A4 and somehow put my S4 motor into that.

Superchargers are available but arent common yet for the B6/B7, I agree that within the next couple years there will probably be more options. However the breaking point of the 4.2 hasnt really been found yet and there arent many cumulative miles on s/c cars. Really no one knows how much the 4.2 can take, for how long, and what will go first.

(JHM is working on this, they just bought a B6 and are making a direct port nitrous system starting with a 100shot then upping it untill they blow the motor)

With the B5 that limit as been found. The ammount of miles put on k04 cars really is impresisve with the hundreds of stage 3 cars there are. You can really almost double the HP on a stock motor with new turbos before you run into problems. I dont know if the B6/B7 motor can take another 200HP.

B5's are allready 7-9 years old. Even without alot of miles time takes its toll. Sitting can be worse that running, and a 35,000 mile car has probably spent alot of its life doing just that, sitting. You can still find cars with less than 100k miles, but you usually pay a premium for the lower miles. Same will be true in 2-3 years.

To be honest there IS alot to replace on the B5. Timing belt is done every 70k or so, turbos have a history of blowing at higher boost, Airbag and ABS control modules like to fry, pixles go missing from the display, transmission locks up, suspension binds itself to death. 02's, EGT's, Oil temp + level senders, and all kinds of other sensors fail. CV boots, brake rotors, really the list never ends. Obviously you wont have all these problems at once, and some of them will allready be fixed and dealt with for you by the previous owners.

So is it worth it? To me, YES! My next S4 will definitly be a nogaro, and yes i do plan on getting another one at some point. If the car makes you happy then its ALWAYS worth it. If you dont want a car that you have to put money into, the S4 probably isnt the car for you, because it will cost a couple throusand a year if you want to keep it running.

People still buy the C4 S4's and put money into them and theyre as much as 17 years old. The I5 turbo is a beautiful motor...

 

thanks again, really great replies from everybody

I didn't realize that the newer S4s had not been tested (and tuned?) as much as the B5s .. that being said, I want a B5 too, but I feel like buying an old car and replacing everything in it (or a very substantial amount of things) is not what I want to do - I think. I guess it'll depend on the car, so we'll see how things play out ..

Okay so ! Wear and tear -
Do S4 motors run 150k miles (even with K04's?) and how do the trannies hold up too? I'm wondering because I want to get a feel for the 'lasting power' that has been seen from these cars.

Thanks again for all of your help

 

did a compression test on my b5 2.7t when i did the rs6 swap and at 140000 all cylinders are still pushing 155 psi but one.. im assuming it could be minor and would explain why the car is still smooth as silk accelerating and idling.. transmissions do go sooner.. synchros between 1 and 2 tend to go.. theres a lot of r+d into cryo treating a rebuild for it...

 

If the car is maintained throughout its life you wont have alot of problems, if its neglected and abused you will. By no means will you be replacing every part on the car but there are certainly parts that tend to fail eventually. The s4 will run to 200k miles for sure. People have made it past 150k on stock turbos, obviously they will last much longer at the stock 8-9lbs of boost than a GIAC chip spiking to 18lbs. Proper warm up and cool down and frequent oil changes will help alot. Its a good car, just not one you neglect or treat like a honda civic.

The transmission (im speaking of 6speed) is good except the tolerances on the synchros are too tight so missed shifts, agressive downshifting, general transmission abuse can cause some problems. Most of the time the result is not being able to get into 1st or 2nd gear, sometimes reverse and 3rd can be affected too. I cant up shift into 3rd above 3000rpm or at WOT because of this issue, however i have a complete rebuilt kit from JHM that will completely fix and prevent the problem from happening again. Its not bad enough to affect daily driving, im never locked out of lower gears, but i want to deal with it NOW. price: $1100 in parts.

Some people say these cars are just getting broken in at 100k miles, many many people dont even go stage 3 untill after 100k rolls over. It was a 40,000+ car new so first owners were often adults who werent modifying or beating on them, now many years, miles, and owners later they are cheap and lots of people buy them to modify.

The B6 and B7 are just newer so there hasnt been as much time, in 5-7 years there will be much much more available. Even now theres a decent ammount of stuff available. You can get an ECU remap, JHM longtube headers, nice coilovers, lightweight brakes and wheels, clutch, shifter and youll have a nice car, but as far as performance a B5 S4 with the same mods will be about equal. Interior the new cars win hands down... Beyond that its a little harder, not impossible, but certainly not the wealth of options the B5 has.

 

great replies, and some of it is really interesting. how much do the synchros affect aggressive downshifting? are you saying that you can't double clutch a downshift @ over 3k rpm?
otherwise thanks again, its a lot of info and i have a really good picture (at least i think lol) of how long these cars last and an idea of what kind of things are common replacements
and now i have an idea of what kind of 'upgrade paths' are available with the different models. the b5 has a lot more options, but in the future the b6/b7 may have some too..

thanks again i really appreciate all the advice you guys have been giving

 

Well ask your self first of all if you want turbo or NOT. Because there are more parts to change out with the C4 and B5 line = more $$$

SourD has given you a lot of pertinent information all of which you should take into consideration.

I personally like the B5 S4 over the B6 or B7. Had you asked about the C4 I could definitely give you my scope on that. =)

Ultimately you want something you can have fun driving and not have so much headache with. C4S4 and B5S4 are getting older so a lot of times you will be tempted to upgrade and then get the "while i'm in here" bug and start doing standard maintenance items driving the cost of your project up. Turbos just open up this entire avenue of tuning options - which can be a headache.

Sometimes its almost a gift not to have so many tuning options (b6 & b7)... you spend less time worrying about what you're gonna do next =)