Alignment Basics

Discussion in 'Modifications & DIY how-to' started by Alex, Sep 17, 2005.

  1. Alex

    Alex Community Founder Staff Member

    I'm putting this together to help explain the importance of a great alignment. A big thanks goes to Big Sky for the writeup. Some of this is coming from his thread over on ClubWRX and some is my own interpretation (there's only so much you can say anyways).

    What is Camber? -- Measurement in degrees of the tire/wheel from the front

    [​IMG]

    Why is Camber important?-- negative static (car not moving) camber can help us gain grip in turns, when our cars turn the outside tire wants to go positive, by having neg camber this positive change is negated and we optimally get a flat, wide contact patch.

    Excessive neg camber can degrade straightline braking (less contact patch) and can cause excessive tire wear (not as much as you'd think though- ore on that w/ toe).

    The oe spec for front camber on the WRX is -0.25- that's not a lot, especially for a performance orientated car. The WRX's upper strut bolt is eccentric and allows for adj, w/ the stock bolt- it's common to be able to get close to -1.4 degrees w/ the oem bolt. Camber plates (or caster camber plates) can increase this to close to -2.5 - -3.0. Some have also combined a camber bolt in the lower hole w/ the oem bolt to increase camber.

    The oem spec for rear camber is -1.3, there is no adjustment in the rear oem, many use camber bolts in the rear to provide adjustment.

    The oem specs provide for limited performance and help promote understeer- by increasing front neg camber you dial out some understeer, by adding positive camber to the rear you do the same. With camber bolts in the rear you can add some positive camber and dial out some understeer- you don't want to dial out too much though as you still want static neg camber for improved grip in corners.

    What is Cross Camber? -- the difference between left and right camber settings, you want this as close to zero as possible.

    What is Caster? -- the angle of the steering pivot, measured in degrees, when viewed from the side of the vehicle.

    [​IMG]

    Caster also expresed in degrees, can help w/ performance as it goes more positive (ALK or caster/camber plate) it has the same effect as adding static negative camber. It also provides for straight line stability. It is not adj oem.

    The oe specs for the WRX are ~ 3.5 degrees, the ALK adds ~ .5 degrees, caster/camber plates ~ to 1.5 degrees.

    Most feel there are no negatives to increased positive caster (a little heavier steering effort), some cars run w/ as much 8 degrees.

    With caster plates you are able to control cross caster as well.

    What is Toe? -- The toe measurement is the difference in the distance between the front of the tires and the back of the tires

    This is "toe in":
    [​IMG]

    Toe is adjustable both front and rear, the oem specs are 0 (+/- 3mm)- toe is adjusted in the front via the tie rods in the rear via the rear lateral links.

    Toe contributes more to tire wear than camber, thus most reccomend near 0 toe. Toe can also effect performance, toe out in front will help w/ turn in, toe out in the rear w/ rotation, toe in front and rear w/ high speed stability. People play w/ toe for performance gains, but make sure you know what you are doing befoer considering something other than very near 0 toe.

    Cross toe is important as well, again as close to 0 as possible.

    The Do's and Dont's of any Alignment

    -do request a before and after printout
    -do tell them you want cross toe and camber as close to 0 as possible!
    -it's better to give them specific specs vs just getting it to "spec"- spec can range from positive camber on one side to neg on the other, toe in one side- toe out on the other- the factory specs are pretty wide (too wide!)
    -some shops won't do "custom" alignments- know that before going in
    -if your shop is having trouble getting front neg camber approaching -1.0+ tell them the lower strut bolt needs to be loosened as well to achieve this- you won't belive the # of shops that don't know this

    So here you have it, these are just the basics for any alignment that anyone should be aware of and familiarize themselves with. This is one of the most important (and necessary) aspects of suspension performance. There are a few places I'd recommend for an alignment. Scott Siegel over at Subaru of Gwinnett ($150 for a Performance Alignment) and also the guys over at Gran Turismo ($100 ish I think).
     
    Last edited by a moderator: Sep 20, 2005
  2. monk

    monk <b>The Kitchen Ninja!!!!</b>

    excellent info, thanks alex!
     
  3. Meredith

    Meredith Banned

    I'd recommed Jeff at Gran Turismo to anybody. The alignment will cost about $80 or $85 i believe. Brian's been taking his car(s) there for the past five years and the service has always been awesome. Can say enought about this shop! Nice info alex!
     
  4. monk

    monk <b>The Kitchen Ninja!!!!</b>

    how long do they usually take to do a perf alignment? i gotta go there right after my tein install next week
     
  5. Meredith

    Meredith Banned

    Umm about an half and hour i believe. You can call for an appointment, they are usually really busy. On thursdays they are open until 7 pm at night. I'll be there getting my victoracers mounted and balanced.
     
  6. monk

    monk <b>The Kitchen Ninja!!!!</b>

    awesome, can you give me their number?
     
  7. Alex

    Alex Community Founder Staff Member

    SS spends about an hour on a perf. alignment. It all depends on how much the car resists to fine tuning.
     
  8. Meredith

    Meredith Banned

    My Bad, Gran Turismo phone number is 770-455-0347
     
  9. WrxCrazy

    WrxCrazy Active Member

    can u please post up address to gran turismo please...
     
  10. pEd

    pEd This ain't no Piccadilly!

  11. gueryjones

    gueryjones Member

    Last two times I've been to GT East for an alignment, everything hasn't been tightened down completely and I had to tighten bolts down myself to eliminate rubbing or clanking. The first time I figured it was just bad luck. The second time... Something to think about.
     
  12. pEd

    pEd This ain't no Piccadilly!

    Wow....
    I think this is the first time I've ever heard any bad stories about them.
    Good to know though. Certainly worth looking out for.
     
  13. knhtrdr

    knhtrdr Active Member

    would you need an alginment for new rims/tires also or just suspension?
     
  14. crashtke

    crashtke Member Supporting Member

    Yap, I usually get my car lined up after every new tire purchase. If you are getting new rims that are not factory, time to line it up.
     
  15. pEd

    pEd This ain't no Piccadilly!

    it's always a good idea to get an alignment.
    If no other reason to make sure that you're not going to
    wear the tires out, you've got a much bigger contact patch now.
     
  16. Alex

    Alex Community Founder Staff Member

    With the new size/offset of the tires you just picked up fareed I'd definately recommend at least having a checkup done to see what may or may not be the most advantegeous setup for yourself.
     
  17. knhtrdr

    knhtrdr Active Member

    cool,thanks
     
  18. knhtrdr

    knhtrdr Active Member

    Done! they asked what would I be doing I said street, autox but not so much cause I have the stockers for that.
    before:
    Front
    Left camber -0.6 Right -0.4
    cross camber -0.2
    L caster 3.3 R 3.3
    cross caster 0.0
    L toe -0.4 R-0.11
    total toe -0.16

    Rear
    Left camber -1.4 right -1.3
    L toe 0.04 R -0.13
    total toe -0.08
    thurst angle 0.17

    After:
    Front
    Left camber -0.6 Right -0.4
    cross camber -0.1
    L caster 3.3 R 3.3
    cross caster 0.0
    L toe 0.0 R 0.0
    total toe 0.01
    Rear
    Left camber -1.4 Right -1.4
    L toe 0.04 R 0.04
    total toe 0.08
    thurst angle 0.01

    Ok what is thurst angle? would it be safe to run this in autox or just use my stockers? and with these numbers what kind of suspension would I need to look into. they will still rub a bit but not like before.
     
    Last edited: Sep 11, 2006
  19. knhtrdr

    knhtrdr Active Member

    Now I hear squeaking when I turn is that normal?
     
  20. miloman

    miloman Retired Admin

    mine squeaks all the time
     
  21. calmnothing

    calmnothing Shlimp Flied Lice Supporting Member

    why is there that much more neg camber in the rear?
     
  22. knhtrdr

    knhtrdr Active Member

    I have no Idea Im guessing cause I told him I may be autoxin? I dont know but I can take corners better without so much rub.
     

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