GT PP suspension too springy- hurts neck

Discussion in 'Suspension, Brakes & Chassis' started by 1stBluesCup, Feb 13, 2020.

  1. DRB

    DRB Well-Known Member

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    Thanks.
     
  2. OP
    OP
    1stBluesCup

    1stBluesCup Active Member

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    I've heard the PP springs are soft, now you say they are stiff. So which is it-- soft or stiff? BmacIL said it's the shocks that are too stiff and don't handle the rebound, and springs are soft.
     
  3. BmacIL

    BmacIL Enginerd

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    The pp springs are very minimally stiffer than non-pp. They're not stiff spring rates. With a better damper tune the car will lose the bouncy feeling and will be more planted and controlled in all situations.

    Magneride offers the opportunity to run slightly softer springs and retain control in all situations. The real magic happens when you have moderately stiff springs that still ride decent, and then the magneride can offer truly tight and sharp body control. Enter the BMR magneride handling springs, for instance.
     
  4. shogun32

    shogun32 Well-Known Member

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    The rear PP1 shocks have insufficient rebound damping - IOW too soft. The PP1 springs are good enough for casual street use. For moderate to serious autoX or track use the PP1 springs have too low a rate. You want around 250F, 800 but closer to 1000R is more suitable for that kind of usage.
     
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  5. hiccup

    hiccup Well-Known Member

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    The front factory perfpack set is fine
    The front factory perfpack suspension is fine but your factory rear shocks are the issue..I chose the rear Koni orange str.t's a few years ago after my low back gave me trouble..A very noticeable difference I'd say.
     
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  6. OP
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    1stBluesCup

    1stBluesCup Active Member

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    I don't know, feels like the whole dam car bounces violently on these Dallas concrete roads!
     
  7. shogun32

    shogun32 Well-Known Member

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    Do the rears first (only about $350) and then you'll know if you need to spend more.
     
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  8. Genxer

    Genxer Well-Known Member

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    I run tire pressure at 32 F / 29 R which seems to be a good balance for me. Interesting about the shocks making such an improvement. I really don't want the car lower, so that might be the next upgrade for me in regard to the suspension.
     
  9. rucus0101

    rucus0101 Well-Known Member

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    Rears are easy if you are just doing the shocks also.
     
  10. KellTrac

    KellTrac Well-Known Member

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    The factory 15-17 PP suspension can be a little jittery. Throw in some common IRS modifications that eliminate the compliance within the rear system and it can become exaggerated.

    When these cars came out I did a lot of testing and one of the easiest and quickest ways that I found to eliminate what I would call excessive jounce, was simply clocking/indexing the suspension mounting point bushings and trimming the rear bump stops 5/8" up to 1.25" or so. The PP cars utilize the bumpstops during normal operation and I found the bounce to become worse when removing the rubber deflection.

    If you have not tried to trim the rear bump stops I would highly suggest doing so, it may work for you and put the ride at an acceptable level.
     
  11. H@mmer

    [email protected] Well-Known Member

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    Factory PP suspension was *not* good.
    I put Steed shocks and linear springs on my car and not only did it handle better, but it rode better.

    Weird thing is, I put my GTPP shocks, along with some Steeda progressives, on my wife's base Ecoboost, and it made it ride better.

    I just don't think the GTPP shocks are a good match for the heavier GT along with the stock springs.
     
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  12. rucus0101

    rucus0101 Well-Known Member

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    You are correct. I am only a suspension novice but from what I could tell the rear shocks just don't have the dampening to deal with the PP springs.
     
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  13. Genxer

    Genxer Well-Known Member

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    So some of you guys simply replaced the rear shocks and didn't touch the fronts, and the ride is better balanced? Just trying to understand the results ppl are getting.
     
  14. BmacIL

    BmacIL Enginerd

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    Yes, it's a solid first step. There are some of the FP track rears for sale on here, and LMR also carries them individually. Or, you can get the whole damper set for ~$520 from Whitebear Lake Ford.
     
  15. BmacIL

    BmacIL Enginerd

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    Yes. They are too aggressive on compression and not enough control on rebound. It makes for an unnecessarily bouncy, jittery ride.
     
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