Need advice on my suspension

Discussion in 'Suspension, Brakes & Chassis' started by krishelnino, May 4, 2020.

  1. krishelnino

    krishelnino Well-Known Member

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    #1 krishelnino, May 4, 2020
    Last edited: May 8, 2020
    It's been almost 1.5 years on my current setup. However now that i'm planning on doing a rear diff upgrade from 3.55 to a Torsen 3.73 gears, i figured i'd redo some of the suspension. I'm not very knowledgeable in this area but going through a ton of posts in the past few years and most members recommendations, i'm going to tweak it a little bit to further improve the handling

    Current setup:
    FP Track Handling shocks, struts and spring
    FP Track Handling kit swaybars front and rear
    Steeda IRS subframe braces, subframe bushing and alignment kit
    Steeda front control arms - lateral and tension links with bushings
    Steeda bumpsteer kit
    FP strut tower brace, firewall brace and PP lower K member
    Steeda Camber plates
    recently upgrade to SVE 19x10 285/35 squared

    I have no issues with the ride quality it's comfortable enough on most roads. However the main issue that i'm having is that car doesn't feel planted on highway surfaces which are uneven, like mostly roads which are under construction and the road level constantly keeps changing. I don't have enough confidence to push it hard on uneven surfaces, because get a slight float feeling. The best way to describe is the rear end feels kind of loose/not planted enough. After switching the wheels and tires I also have a bit of oversteer now. The other issue is sometimes accelerating through sharp turns i feel the rear end not sticking as much - the car doesn't put the power down properly (i hope the Torsen diff will be an upgrade in this department)

    Planning to swap out/add the following:
    Change FP Track springs to BMR SP083 or GT350R springs
    Change the swaybars ? Is this needed or the FP ones good enough. haven't decide on this yet
    Add Steeda Rear LCA Bearing
    Add BMR Vertical Links TCA048 Polyurethane
    Add Steeda Rear Shock Mounts

    Torsen 3.73 diff
    MGW X-Spec shifter

    It's been a while since i got an alignment but it's -1.5 Front and -1.3 rear camber with slight toe in

    My car is a daily driver and i only occasionally track it, i've done like 3 track days on my old setup. If there's anything else i've missed please let me know
     
  2. Brian@BMVK

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    You're thinking the right way with all of that for sure. I'd keep an aftermarket bar on the front only.
     
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  3. OP
    OP
    krishelnino

    krishelnino Well-Known Member

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    Thanks, any recommendations for the front swaybar? BMR or Steeda?
     
  4. Brian@BMVK

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    Keep the FP bar. No reason to spend more for something that's going to be more or less functionally equivalent.
     
  5. shogun32

    shogun32 Well-Known Member

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    what are your clicker settings and bar positions?
     
  6. OP
    OP
    krishelnino

    krishelnino Well-Known Member

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    I think they were set to the soft setting, haven't changed it since
     
  7. shogun32

    shogun32 Well-Known Member

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    Leave bars alone but I would try a half turn of rebound and do the 'better? or worse?' test. The more I play with my setup the more I'm mystified why 'full soft' is the commonly recommended setting.
     
  8. Grintch

    Grintch Well-Known Member

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    You know the bars are adjustable right? I am currently running mine Stiff/medium and that is somewhat pushy with square tires. Been thinking of moving to stiff/stiff (also FP Track Pack).

    OP - you're not running near enough camber for track use (I am currently at -2.7/1.8 and could use more).
    Is your loose setup confirmed by tire wear (particularly on track), or is it more of a feel issue?

    I don't see anything in your new plan that is an obvious fix to a loose condition. What do you have the sway bars set to? Run them stiff front/soft rear and they will be at their tightest settings.
     
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  9. Brian@BMVK

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    Significantly stiffer than stock rear bars only make the car feel "good" / "balanced" at <7/10ths, unless you have it with a really stiff front roll couple. If you push it, they don't inspire confidence and don't help put power down.
     
  10. Brian@BMVK

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    Sounds like the rear springs are too soft....
     
  11. OP
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    krishelnino

    krishelnino Well-Known Member

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    I use mine as a DD on the street so don't want to run an agressive alignment, and i'm following BMR's street handling alignment specs. I just checked the swaybars and it's set to soft/soft on both front and rear (outermost setting). So you're saying the RCLA bearings, vertical links and shock mounts don't help with the rear end ?
     
  12. Grintch

    Grintch Well-Known Member

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    The springs are not adjustable, but the anti roll bars are.

    I haven't seen any spring rates for the Track Pack springs. They are progressive, so even if numbers were available it's hard to compare them.

    I will say I was surprised after driving a GT350 that the standard GT350 springs felt stiffer than the Track Pack springs, but given different shocks (especially variable damping MR shocks), that is hard to compare them apples to apples as well.

    I am pretty happy with how the Track Pack + camber plates work on road & track. And that is without any of the stop the hop hardware. But despite the name they are biased more for the street.
     
  13. Grintch

    Grintch Well-Known Member

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    They wouldn't be a direct fix to an oversteer issue, like adjusting the anti-roll bars would.

    If your issue is a loose or imprecise feel in the rear rather than loose handling (oversteering), then they are probably more on point.

    I thought you said you drove the car at the occasional track day? With the recommended FP Track Pack alignment settings, which are more aggressive than yours, I didn't make it through my first track weekend in the car before I blistered a tire form not enough camber. Even now, the outsides edges of the tires still suffer.
     
  14. OP
    OP
    krishelnino

    krishelnino Well-Known Member

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    did couple of track days last year, that was a small technical track and my first time. However I was on OEM PP wheels back then, I've changed wheel setup early this year running squared and wider 285/35 tires. I haven't tracked with this combination but mostly notice the oversteer on the street
     
  15. OP
    OP
    krishelnino

    krishelnino Well-Known Member

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    Ok, after much thought and going through a lot of the threads, i've decided to do the following. I'd do this only once so i'm following the route that has been successful for many members on here.

    1) Swap FP Track springs to BMR SP083R
    2) Change front FP swaybar to BMR 3 way adjustable
    3) Change rear FP swaybar to OEM PP/GT350
    4) Add Steeda rear shock mounts
    5) Add RLCA bearing - still debating kinda undecided
    6) Add BMR TCA048 vertical link - i'm thinking this wouldn't make much of difference but it's not that expensive figure i'd throw it in
    7) Add Steeda diff bushings - the red ones

    I should be able to sell my FP springs and swaybars which would offset some of the costs involved

    I guess my rear suspension would be complete and along with 3.73 Torsen + MGW X-Spec shifter it should transform the car :) I will report back in a month or so when i get them all installed.
     
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