1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Tyre pressures

Discussion in 'A3/S3 Forum (8L Chassis)' started by concoursneil, Dec 23, 2005.

  1. concoursneil
    Online

    concoursneil Member

    Joined:
    Aug 31, 2003
    Messages:
    327
    Likes Received:
    1
    Can anyone tell me the tyre pressures i hould be using on 225 40 18's please front and rear as ive just bought new set of wheels
    /ubbthreads/images/graemlins/beerchug.gif
    #1
  2. dickys3
    Offline

    dickys3 Moderator Staff Member Moderator

    Joined:
    Oct 13, 2003
    Messages:
    2,955
    Likes Received:
    1
    36 all round...

    Or try 36 rear, 34 front...
    #2
  3. starski4578
    Offline

    starski4578 Member

    Joined:
    Aug 29, 2005
    Messages:
    147
    Likes Received:
    0
    I've always put 30 all round!! is it 36? seems alot but i'll change if thats the recomended.
    #3
  4. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    6
    36/36 is what Audi suggest...

    Personally, I found that awful...too much understeer so I used to run 34F/38R...which gave much better grip and less understeer.
    #4
  5. S3Steve
    Offline

    S3Steve Active Member

    Joined:
    Sep 7, 2005
    Messages:
    1,592
    Likes Received:
    11
    36psi seems very high I would have thought 30psi.
    #5
  6. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    6
    [ QUOTE ]
    36psi seems very high I would have thought 30psi.

    [/ QUOTE ]

    Generally, pressures go up as profile decreases...Audi do say 36/36 for an S3 on 18s.

    30 is far too low to get the back of an S3 to do anything meaningful...you'll need more wind in there to get it into play...
    #6
  7. Markb
    Offline

    Markb Active Member

    Joined:
    Apr 4, 2004
    Messages:
    2,139
    Likes Received:
    1
    Hmm I've been told to use 31-32 by most people I've spoken to.

    Will have to look into this.
    #7
  8. elucidate
    Offline

    elucidate Member

    Joined:
    Dec 4, 2005
    Messages:
    157
    Likes Received:
    0
    I run 38 Rear, 34 Front and it makes an amazing difference to the way the car runs.

    Pressure needs to go up as profile goes down.


    I think originally it was here that someone suggested those pressure and boy, what a difference!!
    #8
  9. Markb
    Offline

    Markb Active Member

    Joined:
    Apr 4, 2004
    Messages:
    2,139
    Likes Received:
    1
    Wow got to go and try this now.

    Got me thinking.
    #9
  10. Ryanc
    Offline

    Ryanc Active Member

    Joined:
    Feb 15, 2004
    Messages:
    1,321
    Likes Received:
    0
    was going to ask this,nice one!!
    #10
  11. jojo
    Offline

    jojo S3 Drift King! Staff Member Moderator

    Joined:
    Sep 4, 2003
    Messages:
    25,935
    Likes Received:
    1,561
    19" wheels, I'm using 35F and 39R, this is good in the dry and track, but **** in the wet!
    #11
  12. Ryanc
    Offline

    Ryanc Active Member

    Joined:
    Feb 15, 2004
    Messages:
    1,321
    Likes Received:
    0
    Got the alloys by the way they look nice,will put them on tommorrow and post some pics.
    #12
  13. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    6
    [ QUOTE ]
    I run 38 Rear, 34 Front and it makes an amazing difference to the way the car runs.

    I think originally it was here that someone suggested those pressure and boy, what a difference!!

    [/ QUOTE ]

    That's likely to have ben me...
    It's a massive difference in grip, turn-in and reduction in understeer, over standard.
    #13
  14. concoursneil
    Online

    concoursneil Member

    Joined:
    Aug 31, 2003
    Messages:
    327
    Likes Received:
    1
    Cheers guys will have to have play with pressures and see whats best
    #14
  15. elucidate
    Offline

    elucidate Member

    Joined:
    Dec 4, 2005
    Messages:
    157
    Likes Received:
    0
    [ QUOTE ]
    That's likely to have ben me...
    It's a massive difference in grip, turn-in and reduction in understeer, over standard.

    [/ QUOTE ]

    It was, thank you thank you thank you!

    World of difference...
    #15
  16. Khufu
    Offline

    Khufu Active Member

    Joined:
    Jan 2, 2003
    Messages:
    5,703
    Likes Received:
    30
    are we only talking about quattros only or FWD too?
    #16
  17. Markb
    Offline

    Markb Active Member

    Joined:
    Apr 4, 2004
    Messages:
    2,139
    Likes Received:
    1
    [ QUOTE ]
    are we only talking about quattros only or FWD too?

    [/ QUOTE ]


    I was wondering this as well.
    #17
  18. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    6
    [ QUOTE ]
    are we only talking about quattros only or FWD too?

    [/ QUOTE ]

    Even more so FWD!

    On a quattro you need the rears to give a little to enable them to provide drive...a sliding rear end isn't providing maximum grip...

    On a FWD car the rear only has to follow the front...like a pair of castors really...so it's accepted practice to get the front gripping and then set the rear pressures higher...

    Try the fronts at the setting for 2 people and no luggage (or even slightly less to aid grip, feel etc)...and the rears at the setting for 4 people and a boot full of luggage (or even slightly more)

    That should be a good starting point...

    On the road, I don't like the rears being too high on a FWD car, otherwise it gets unstable and it likely to swap ends if you lift off mid bend...but I do like it to be at the point of breaking away with little provocation to enable the rear to rotate.
    Lift off oversteer is great if you have lots of grip at the front (aggressive suspension angles, sticky tyres and an LSD - which I do) but no use if you can't power out of the slide you have put the car in....so be careful how high you go on rear pressures.


    I can't remember what I run my Golf at...something like 30F/35R or 32F/36R, somewhere around there. That's on 215/40/16s on 7" x 16" BBS wheels.
    I'd know if I saw what the Mk3s run standard...but that's in the right ballpark.

    Play about though...
    #18
  19. starski4578
    Offline

    starski4578 Member

    Joined:
    Aug 29, 2005
    Messages:
    147
    Likes Received:
    0
    Interesting stuff, i will be giving it a try soon as. Have always gone for 30/30 on all my other cars but sounds like it can make a massive difference. Cheers
    #19
  20. SilverBullet
    Offline

    SilverBullet Bullet

    Joined:
    Nov 27, 2006
    Messages:
    11
    Likes Received:
    0
    for 225 45 17 ?? my pressure is 32 is it fine? :think:
    #20
  21. leecs3
    Offline

    leecs3 thinking about stuff

    Joined:
    May 13, 2006
    Messages:
    604
    Likes Received:
    2
    higher pressure = less friction (grip)
    lower pressure = more friction (grip)

    Basically experiment front to rear to you find a balance your happy with. F1 cars run 1.1 bar which is about 18psi!!!
    #21
  22. A3_Turbo
    Offline

    A3_Turbo Swaying towards IHI....

    Joined:
    Jul 28, 2006
    Messages:
    1,464
    Likes Received:
    0
    Yeah I used to do alot of racing myself, And the general rule is lower PSI more grip but your tyres wear quicker, and the opposite way more PSI less grip because less rubber is being laid down and your tyres dont wear as much.

    So when racing you change your pressures according the the car set-up, Weather and how many laps. Some times when it was hot, and too much grip being laid down you'd find it hopping.

    Im going on a bit there as you dont need to know that, but unless your driving your car hard you wouldnt want to change from what audi suggests surely?

    But then if you are just experiment there is no right tyre pressure it has to be what feels right for you. For example some-one may like understeer and say use 28-32 you may not like understeer so it wouldnt be right for you.

    Just try and experiment a few different combos.

    But as i said if your not driving the car hard just poodling to work then you dont need to worry you'd probably be better off putting what audi sugest as all you'll just be worried about is tyre wear if your not driving it hard.

    Rant over.....


    Jason
    #22

Share This Page