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

Forgetting what you've learned...

Discussion in 'Detailing' started by Mutley, Oct 8, 2003.

  1. Mutley
    Offline

    Mutley Member

    Joined:
    Jan 3, 2003
    Messages:
    67
    Likes Received:
    0
    [Oct 8, 2003]
    An interesting site I came across http://www.virtualv8.com/ggdiag.htm

    This explains how it may be possible (on a track /ubbthreads/images/graemlins/grin.gif ) to maximise cornering speeds by applying the brakes INTO a corner - after all, we all accelerate out of a corner...

    Any thoughts?
    /ubbthreads/images/graemlins/beerchug.gif
    #1
  2. Ads

    Ads

    [Sep 24, 2014]

  3. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    6
    [Oct 9, 2003]
    A few of my thoughts on trail braking:

    I use trail braking on the road. I also use it on the track...a lot!
    I started using this type of technique to get the front end of front wheel drive cars like of my old modified Nova to turn in as I wanted, and to get the back to come round nicely...but I agree, It's risky...aspecially as you say, in the wet.

    So long as you have a very well set up front end that you can lean on hard, and load right up, trail braking usually works well...but you also need the rear end not to be too snappy so as not to catch you out.

    To make it work well, you also need (in my view) a decent amount of power (& torque), good traction (LSD essential) and immediate throttle response (be in the right gear).

    My old Nova would let you do it...my Honda Integra Type-R would let you do it, and my current Mk3 Golf GTI 16v will (now it's set up for it)...but the S3 won't.


    Hell, I've tried...but on the S3 the problems seem to be:

    The front end is too hard to get set up with enough bite...no LSD which doesn't help! It always tends to understeer when pushed, and thus if you can't get the pivot point (inside front wheel) firmly planted, the technique fails.
    The throttle response is not immediate...lag to contend with.
    The car is too hard to balance on the throttle whilst trail braking as the throttle is cut with the brakes on, regardless of what you do with the right pedal.


    The technique is sound...but getting a road car set up to allow you to exploit it safely is a difficult job, and will always carry a high risk.
    #2
  4. acf8181
    Offline

    acf8181 Member

    Joined:
    Oct 11, 2003
    Messages:
    97
    Likes Received:
    0
    [Oct 13, 2003]
    my golf vr6 tends to have the rear end snap out if you do it, but i used it great effect yesterday when racing a formula first.

    'ess three' - what have you altered on your mkIII golf gti to enable it to do it? and did you also get a snappy rear end on it before you fettled with the suspension?
    #3
  5. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    6
    [Oct 13, 2003]
    [ QUOTE ]
    acf8181 said:
    my golf vr6 tends to have the rear end snap out if you do it, but i used it great effect yesterday when racing a formula first.


    [/ QUOTE ]

    Wow! Assuming it's a Mk3 Golf VR6...they are normally understeering everywhere and getting the rear and to move at all is some undertaking!

    [ QUOTE ]

    'ess three' - what have you altered on your mkIII golf gti to enable it to do it? and did you also get a snappy rear end on it before you fettled with the suspension?

    [/ QUOTE ]

    No snappy rear end on my Mk3 ever...it would always tend to understeer...so much so that getting it to the point of having enough grip at thwe front to contemplate trail braking was reasonably tricky. Even on the limit it would slide progressively and evenly in a 4 wheel drift...definately not snappy at the back.


    Anyway...my current set up(this is on a 16v GTI...so less front end weight to contend with as a starting point):

    Koni coilovers (front damping set close to minimum, rear damping set about 1/3rd up from softest), Eibach anti roll bars, full Powerflex bush set, maximised front castor by moving the front subframe, 1.8 degrees front negative camber each side, 0.5mm front toe out each side, Toyo T1-S 215/40/16 tyres on 7" x 16" rims, Quaife ATB LSD and 3.94 FD.

    Basically, I've upped the front grip by sorting the suspension and tyres, added traction with the diff and lower FD and made the rear a bit more mobile by adding the bigger Eibach rear bar. Added to the whole car being a bit tighter by virtue of the stiffer bushes, it rotates nicely now...and as long as you are in the right gear and keep your right foot down, it'll pull through regardless of what the rear starts doing.

    In saying that...it turns in so well not that there's no rear need to provoke a wagging tail by trail braking. It'll do it controllably, but under normal driving you don't need to.
    #4
  6. acf8181
    Offline

    acf8181 Member

    Joined:
    Oct 11, 2003
    Messages:
    97
    Likes Received:
    0
    [Oct 14, 2003]
    i know what upgardes i want but its down to money (or the lack of it), here's my dream list...koni TA, eibach springs, 25/28mm ARBs, poly bushes absolutly everywhere, gemini 6 spd conversion with custom ratio's, torque biasing diff (believe they're slightly better than LSDs, schrik vsr inlet, corrado throttle body, re-map, seat brembo brakes.

    chances of it all happening..0, unless i win lotto!!

    i don't really notice any twitchyness in a staright line, but then its not the kind of thing that would bother me (i've raced a bit). i also, get no problems with tyre wear and may consider increasing the camber if i get new susp (or castor if i get eccentric top mounts), as i love the extra responsiveness you get out the steering.
    #5
  7. Ess_Three
    Offline

    Ess_Three Active Member

    Joined:
    Feb 19, 2001
    Messages:
    5,383
    Likes Received:
    6
    [Oct 14, 2003]
    [ QUOTE ]
    acf8181 said:
    torque biasing diff (believe they're slightly better than LSDs)


    [/ QUOTE ]

    The Quaife LSD is a torque biasing diff...

    Personally I've used two types, clutch and plate and ATB...the ATB like the Quaife is great for the road, but only 'locks' if you like, on power on...so it's great for traction and is reasonably transparent on the road.

    For track work I prefer a clutch and plate type which tends to be far more vicious in it's application but can provide locking on both power on and braking.
    I used a ZF 40% locking LSD years ago....incredibly predictable on the track but you needed arms like Arnie to keep the car straight on the road!


    [ QUOTE ]

    i don't really notice any twitchyness in a staright line, but then its not the kind of thing that would bother me (i've raced a bit). i also, get no problems with tyre wear and may consider increasing the camber if i get new susp (or castor if i get eccentric top mounts), as i love the extra responsiveness you get out the steering.

    [/ QUOTE ]

    With standard bushes flapping about all over the place I suppose it's no great surprise that you don't really notice it...I guess my added toe out also adds to the twitchyness.

    My tyre wear is equal too..

    Just remember that as you stiffen a road car it will roll less on the corners, so loads of negative camber can be a bad thing if you are not getting the car far enough over to get the tyre sitting flat on the road under full lean...
    Also, the profile of your tyres will have an impact...very low profiles, I've found, tend to need less negative for road use.
    #6
  8. acf8181
    Offline

    acf8181 Member

    Joined:
    Oct 11, 2003
    Messages:
    97
    Likes Received:
    0
    [Oct 15, 2003]
    [ QUOTE ]
    Ess_Three said:

    With standard bushes flapping about all over the place I suppose it's no great surprise that you don't really notice it...I guess my added toe out also adds to the twitchyness.



    [/ QUOTE ]

    true about the bushes!! i've have heard elsewhere that adding some toe out is what makes it really twitchy.

    at the mo i still wear out the outside of the tyres first (do you think i drive a little too hard!!!).
    #7

Share This Page