Page 9 of 12 FirstFirst 1 2 3 4 5 6 7 8 9 10 11 12 LastLast
Results 81 to 90 of 120

Thread: The Suspension Setup Thread

  1. #81
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    (quote konakid)

    QUOTE (sr_rolla @ Nov 19 2008, 06:14 AM) *
    the theory is that because the upper and lower arms are at different lengths the diff will try to twist itself as the left and right ends move in different directions (ie: the left moves up and forward while the right trys to move back and down). When u convert the rear end to more solid bushings the diff can no longer pivot in its bushes so the car has a tendency to lift wheels and push understeer. If u drill out the upper bush as u described the diff can pivot as it is meant to do.

    What i would suggest doing is trying the drilled out upper arm 1st and if u feel its a problem later on, get some new bushes.


    Is this why Cusco offer a 5 link with a rose jointed diff end and bushed body end? Seems like that would be an ideal setup.

  2. #82
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    (quote old thread mattyn)

    QUOTE (sr_rolla @ Nov 19 2008, 05:14 AM) *
    the theory is that because the upper and lower arms are at different lengths the diff will try to twist itself as the left and right ends move in different directions (ie: the left moves up and forward while the right trys to move back and down). When u convert the rear end to more solid bushings the diff can no longer pivot in its bushes so the car has a tendency to lift wheels and push understeer. If u drill out the upper bush as u described the diff can pivot as it is meant to do.

    What i would suggest doing is trying the drilled out upper arm 1st and if u feel its a problem later on, get some new bushes.


    so i guess the question now would be WHO ELSE RUNS A POLY URETHANE BUSHED REAR END??? and what have you found...?

    im under the impression that Poly urethane bushes still have some give.. wouldn't the rotational/pivot issues only really come about with a rose jointed un-equal length setup? ie no movement??

  3. #83
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    (quote old thread highlife)

    QUOTE (sr_rolla @ Nov 19 2008, 06:14 AM) *
    the theory is that because the upper and lower arms are at different lengths the diff will try to twist itself as the left and right ends move in different directions (ie: the left moves up and forward while the right trys to move back and down). When u convert the rear end to more solid bushings the diff can no longer pivot in its bushes so the car has a tendency to lift wheels and push understeer. If u drill out the upper bush as u described the diff can pivot as it is meant to do.

    What i would suggest doing is trying the drilled out upper arm 1st and if u feel its a problem later on, get some new bushes.


    I have heard through some guys that race 86's in Australia that you shouldn't do a full unequal length rose jointed trailing arm set-up as it can bind up under certain conditions and cause some unpredictability - your explanation above makes a lot of sense and I can see how it would happen now. Apparently this is solved by going to an equal length rose jointed setup.

  4. #84
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    (quote old thread redsprinter)

    SR_ROLLA ,

    just read the whole thread .. learnt alot and cant wait to try some stuff. but i was wondering if you have and assume you have read "fred puhns how to make your car handle" . Just wondering if this would be a good book for someone who wants to learn about suspension setups and doesnt know all the tecincal lingo ..sorta like suspension for dummies.

    for the suspension team -

    will having too much lock (i do abit of dirfting) cause any negatives to other suspension area for grip driving????

  5. #85
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    (quote old thread chrisso)

    I have poly bushes all round and it was a significant improvement. However, I was starting from a pretty low base as the rubber bushes were completely shagged. The rear is a bit hard, but that has more to do with the overly stiff (temporary) pedders dampers. btw, I used nolothane as the price/availability suited me at the time.

    Chris.

  6. #86
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    how to make your car handle is an awesome book, just b aware that everything is in imperial and the aerodynamic stuff is pretty outdated

    Highlife- yes, if u run an equal length setup none of the issues described above happen anymore as there is no longer conflicting arcs in the 4 link.

    Red Sprinter- i cant see having to much lock being an issue unless the front end is able to invert. There is no way this can happen with a standard style strut (ie, XT130/AE86 style strut as opposed 2 S13 gear)

    With the issue of running a drilled out upper left arm, instead of talking about if it does or doesnt make a difference, is there somebody out there in the real world that has a fully rosejointed rear end? If so, could that person go 2 the wreckers and get an upper arm out of a KE70/AE71/AE86/RA40-60/Corona and drill it out and see what it does? Cant cost more than $20 and an hr or 2 to finallise weather it works or not

  7. #87
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    (quote old thread slydar)

    bill sherwood says it doesnt work and is borderline dangerous.

    i reckon its pretty obvious its a shit idea.

  8. #88
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    QUOTE (slydar @ Nov 22 2008, 02:37 PM) *
    bill sherwood says it doesnt work and is borderline dangerous.

    i reckon its pretty obvious its a shit idea.


    good for bill sherwood, plenty of cars come out with a 3 link, it works, works well and is plenty safe. The theory behind it is solid and its easy to do so whats the problem with giving it a go?

  9. #89
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    (quote old thread samQ)

    ah I love this thread, I wanted to expand on the whole equal length bar thing with an old thread from toymods that I made a while back:

    when the diff when it goes up in a car such as an ae86 the diff rotates and pinion angle changes as it moves up due to two different arc of movement from the unequal length top and bottom arms. This is all good and all but what happens when one side is level and the other side moving up? it doesnt seem like a problem at first but looking closer because of the different axis' of movement between the top and bottom arms it wants to rotate but one side does not because it is at a neutral position. As far as I can see it on one side will in that situation want to stay as it is and the other will try and twist.

    I can only see this be taken up in the bushes and hence why its recommended to drill out the upper top left trailing arm bushes when the rest are upgraded. But what happens when rose joints (spherical joints) are used in the complete rear end? without any deflection allowance I can only see that one side of the diff can move up by twisting the diff housing or testing the sheet metal floor of the car.


    also theres the article I wrote in the faq:

    Multilink rear end tuning


    I am not an expert though

  10. #90
    Senior Member sr_rolla's Avatar
    Join Date
    Dec 2008
    Name
    beau
    State
    NSW
    Location
    Bathurst
    Country
    Australia
    Posts
    435

    Default

    (quote old thread mattyn)

    decision almost made... tongue.gif.. i have rose jointed bars with old rubber bushings at the other end so i'm thinking about using these. yes its still an unequal length setup but I'm hoping that with the following it'll be a good improvement.. Just wanted to run the idea past you all. Thoughts?

    Trailing arms: rose joints (diff) and NEW rubber (body)
    rose jointed castor arms.
    poly-urethane LCA pivot
    poly urethane panhard mounts
    poly-urethane sway bar mounts


    The sway bars bring me to my next question:
    I have Cusco strut bracing front and rear.. the sway bars are stock as far as i can tell.
    With the upper bracing will this cause an unbalanced effect with the stock sway bars or with the new less pliable polyurethane bushes holding them in are these satisfactory....???

    i dont want to do things twice so if i was to find that i wanted to replace the sway bars at a later date i would probably do it now to save buying another set of larger diameter bushes... were all on a budget right!

    thanks again for your help!

Page 9 of 12 FirstFirst 1 2 3 4 5 6 7 8 9 10 11 12 LastLast

Similar Threads

  1. (SA) *E7*/86 BC/AJPS Rear Suspension setup/ 2871r turbo setup
    By sleeper_13 in forum Car Parts For Sale
    Replies: 3
    Last Post: 25th July 2012, 01:06 AM
  2. Need Help With Suspension Setup
    By ArbPotatoes in forum Technical - Questions
    Replies: 22
    Last Post: 30th June 2009, 10:51 PM
  3. The Suspension Setup Thread
    By sr_rolla in forum Technical - Articles
    Replies: 84
    Last Post: 16th August 2008, 02:15 AM
  4. suspension setup
    By AE86_4life in forum Technical - Questions
    Replies: 9
    Last Post: 1st November 2006, 08:43 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •