Remapped 2.8Q impressed.- brake advice!!

[doeboy]

I've posted this in tuning so i won't go on but this morning i took my 2.8Q to Jayson at ChippedUK for a remap. Had problems getting a read on the rolling road becuase the Quattro system kept forcing the car to dropdown a gear because of overdrive. Anyhow without a reading he remapped the ECU and it's so much better, around 18hp he thinks but it pulls so much better, really quite quick.

And the best bit! only cost me £250! Book in guys.

This might be an appropriate time to ask if anyones upsized their rear brakes. My understandings of car mechanics is pittyful, anyhow, is it simply a case of finding a donor's front brakes and swapping them for my rears?

 

[Rev-head]

for the sake of 18HP i would put better discs and pads and that should do you would not worry about the rear

 

[SteveS]

think i'd go for better pads in the rear and get a big brake conversion at the front. mine is standard and ive suffered really bad fade on public roads and ended up with almost no brakes and smoke coming out of the wheels several times, its not funny!! im sure amd technik do a rs4 floating 8 piston brembo kit for b5, b6 cars. it was in septembers audi driver mag.

 

[doeboy]

Rev has a point it's only 18hp. i could upgrade the brake pads/discs and then take it from there. I don't really want to pay more than £200 if i can help it.

 

[Rev-head]

http://www.ebcbrakesdirect.com/car/...make=AUDI&model=A4+Quattro&year=2.8+(99-2000)
http://www.ebcbrakesdirect.com/car/...make=AUDI&model=A4+Quattro&year=2.8+(94-2000)

 

[mckay9uk]

A4 2.4 30v Saloon, I've got drilled standard size front disks and EBC green pads in the front, standard in the rear, massive improvement over standard, dont forget to bleed them as well or better still replace the fluid, this improves brake feel condsiderably, thanks for the above tip i've been looking for a reasonably priced remap for mine as it will shortly be decatted.

 

[Dan Gliballs]

Do you have pictures of your RR printouts? What were your gains at the wheels? (I've heard lots of bad stories on other car forums about them).

I've had RS4 rear brakes fitted, and they made a GREAT improvement

 

[shineydave]

can you explain why they couldn't give you a readout, i've not heard of that problem before on a rolling road

 

[SteveS]

i havent either, did they mean gearbox ecu was confused by the rollers. i asume it is a tiptronic? could of maybe put the shifter in manual mode to overcome the changing down prob?

 

[shineydave]

even if the box was changing down surely they could have taken a reading in the lower gear to provide a reference for before and after the re-map

 

[ZeroK66]

I hope you threw in a new MAF at the same time as mapping, or it was replaced recently?

Brakes... you could get a set of facelift S4 rear brakes which are vented. Or go for RS4 rear brakes which are vented and pretty large.

On the front depending on wheel size you could go for a set of Porche 4-pots and disks. These fit under 17" wheels and work great. More than enough for your setup.

If you are crazy and have 18" or larger wheels you can get the NEW RS4/RS6 brembo 8-pot callipers and a set of RS6 365mm disks. Awesome stopping power, awesome price.

I wish I had replacement the MAF on my 2.8 and also had a remap now... specially at £250!! That is great value. Glad to hear you feel an improvement.

Cheers,

 

[GSB1]

Quite common to have problems with auto box cars on a dyno.

 

[mckay9uk]

I hope you threw in a new MAF at the same time as mapping, or it was replaced recently?

Brakes... you could get a set of facelift S4 rear brakes which are vented. Or go for RS4 rear brakes which are vented and pretty large.

On the front depending on wheel size you could go for a set of Porche 4-pots and disks. These fit under 17" wheels and work great. More than enough for your setup.

If you are crazy and have 18" or larger wheels you can get the NEW RS4/RS6 brembo 8-pot callipers and a set of RS6 365mm disks. Awesome stopping power, awesome price.

I wish I had replacement the MAF on my 2.8 and also had a remap now... specially at £250!! That is great value. Glad to hear you feel an improvement.

Cheers,

Do the facelift s4 rear disks fit with the standard a4 2.4 rear calipers ?

 

[dummi]

do not upgrade just the rear this will mess up your whole brake bias.

however front is ok since this takes most of the load, rear is only there to stabilise.

 

[mckay9uk]

do not upgrade just the rear this will mess up your whole brake bias.

however front is ok since this takes most of the load, rear is only there to stabilise.

I presume the S4 and V6 A4 rear disks are the same size but the S4 disks are vented ? surely this would'nt affect the brake bias ?

 

[shineydave]

early S4 are solid, later facelift cars are vented then of course there's the 99.5 cars that have something else

 

[mckay9uk]

early S4 are solid, later facelift cars are vented then of course there's the 99.5 cars that have something else

i'll have to find out if the S4 with vented disks has the same rear calipers as mine. I'm just about to upgrade the rear's to drilled with green ebc pads. Was going to fit solid disks but if the vented will fit i'll fit those. Has anyone done this upgrade ?

 

[SteveS]

would'nt vented disks need wider callipers?

 

[mckay9uk]

would'nt vented disks need wider callipers?

You will only need another 7-8mm so the standard calipers may fit the piston's wind back a long way.

 

[shineydave]

to be honest i don't think there's anything to be gained by uprating the rears. the fronts take all the braking force because as soon as the weight transfers to the front the back raises and the pressure differential valve cuts in and reduces braking effort to the back brakes to prevent the unweighted back end of the car locking up

 

[SteveS]

i wasnt going to bother with the rears, i think some bigger diameter discs and calipers at the front, and some decent pads all round will be plenty for fast road and a few track days. unfortunatly its expensive!

 

[Dan Gliballs]

to be honest i don't think there's anything to be gained by uprating the rears. the fronts take all the braking force because as soon as the weight transfers to the front the back raises and the pressure differential valve cuts in and reduces braking effort to the back brakes to prevent the unweighted back end of the car locking up

That makes a lot of sense, but I did notice a considerable difference with just the RS4 REAR kit fitted.

The RS4 fronts will be going on whenever I can collar my Audi chappy,..............then I'll experience the REEEEAL difference

 

[doeboy]

Right the Dyno test.

As I understood from what they were saying many 4wd cars suffer the same problem. On the rolling road there's no opposing force as I understand it, just free turning rollers. So during their testing the rear wheels while accelerating hard in 4th gear where turning slightly faster than the front. As a result the ECU sees this and forces the car down in gear. Therefore they couldn't get an accurate reading. Same thing happened in "manual" mode too. Had it been on a real road with resistance then it would be fine, otherwise I wouldn't be here today.

Jayson was good, I’ve only seen recommendations and not problems from ChippedUK. I have to say if you'd driven my car before and after you'd see the difference! Best 250 I spent for years.

 

[dummi]

which RR do they have?

*bear in mind standard front on an s4 brakes are 320mm, you'd be best of upgrading the front first if you wanted to go upgrading, forget rears , especially in this state of tune or until you have the front done. rs4 rears are a great upgrade, but don't try it with 2.8 fronts, this would no doubt offset the brake balance and shineydave says leave the diff to cut up the slack making it pointless.