+ Reply to Thread
Results 1 to 9 of 9

Thread: Progressive vs Linear. Advantages/Disadvantages, etc.?

  1. #1
    Supramania Regular
    Ma70.Ent's Avatar
    Join Date
    Feb 2006
    Location
    NJ
    Posts
    1,871

    Default Progressive vs Linear. Advantages/Disadvantages, etc.?

    What are the advantages/disadvantages of each? Is there any real noticeable difference in handling, etc.? Please end this debate for me

  2. #2
    Grumpy Old Man
    IJ.'s Avatar
    Join Date
    Mar 2005
    Location
    I come from a land down under
    Posts
    39,349

    Default Re: Progressive vs Linear. Advantages/Disadvantages, etc.?

    Our suspension is progressive by nature being double A Arm.

    If you run progressive wound springs you just blow through the light section of the spring with minimal effort.

  3. #3
    Better, Faster, Stronger
    dugums's Avatar
    Join Date
    Apr 2007
    Location
    Chicago, IL
    Posts
    699

    Default Re: Progressive vs Linear. Advantages/Disadvantages, etc.?

    The idea behind progressive springs is that they are somewhat soft under normal load and get progressively firmer as they compress. The advantage of this (if the spring actually works well) is that you have a softer ride when driving normally, but as you start to push the car through corners the springs compresses and the ride firms up.

    Linear rate springs compress in a uniform manner and should be more predictable.

    Some people really like progressive springs for street use, but I don't. The progressive rate springs that I have used have not been that impressive.

  4. #4

    Default Re: Progressive vs Linear. Advantages/Disadvantages, etc.?

    So your saying we wouldn't want progressive springs on our cars, correct?

    I'm guessing it would make the handling feel and work strangely until you got to the stiffer section of the spring. Maybe make the car bottom or feel floaty.

  5. #5
    Offical SM Expert: Suspension & Vehicle Dynamics
    supraguru05's Avatar
    Join Date
    Dec 2005
    Location
    louisville ky
    Posts
    737

    Default Re: Progressive vs Linear. Advantages/Disadvantages, etc.?

    Quote Originally Posted by IJ.
    Our suspension is progressive by nature being double A Arm.

    If you run progressive wound springs you just blow through the light section of the spring with minimal effort.

    exactly i bought the eibac spring kit like 4 years ago and the very first autocross put spring rubbers in removing the biggest (softest) progressive coils.

    for street they seem fine and everyone seems to like them

    but for anything other than that they fall short because you get lots of body roll even with sway bars

  6. #6
    Supramania Regular
    Wiisass's Avatar
    Join Date
    Apr 2005
    Location
    Philly
    Posts
    735

    Default Re: Progressive vs Linear. Advantages/Disadvantages, etc.?

    IJ is right, due to the geometry, there is a slightly progressive effect to the suspension, but this is not as much a progression as progressive springs.

    I don't like progressive springs. With a good damper, there is no need for them. Like others have said, they're soft under small displacements and get stiffer as the spring compresses. They will make the ride more comfortable, but matching a damper to them is hard, so the damper will only be effective during part of the suspension travel. Usually it will have to be soft, so it doesn't overdamp the lower displacement part of the spring, so then it's too soft for the high displacement rates of the spring.

    Basically, they're good for street cars and people who aren't really going to drive their car. I wouldn't suggest them for any type of autox/track days/drifting/etc. People will say they run them and that they do alright, and if they think that, then imagine how much better it could be with a good spring. They also won't provide as good feedback as a good linear spring which is very important when you're trying to go fast.

    Tim

  7. #7
    Supramania Regular
    Ma70.Ent's Avatar
    Join Date
    Feb 2006
    Location
    NJ
    Posts
    1,871

    Default Re: Progressive vs Linear. Advantages/Disadvantages, etc.?

    Are there any linear springs on the market? Most, if not all are progressive.

  8. #8
    Far From Maddening Crowds
    Piratetip's Avatar
    Join Date
    Dec 2005
    Location
    MKE, WI
    Posts
    610

    Default Re: Progressive vs Linear. Advantages/Disadvantages, etc.?

    I will be switching from Eibach Pro to Whiteline linear springs over the winter.
    There are other linear springs available as well...Intrax, ST, Tokico AFAIK
    1 Piece Driveshaft Information
    Critical Speed Calculator

  9. #9
    Supramania Regular
    Wiisass's Avatar
    Join Date
    Apr 2005
    Location
    Philly
    Posts
    735

    Default Re: Progressive vs Linear. Advantages/Disadvantages, etc.?

    I was talking more about going to a sleeve and 2.5" ID spring instead of buying some normal aftermarket setup. It would allow for a better selection of what rates and in most cases a higher quality spring. Plus a bigger selection of sizes and the spring sleeve would allow for some height adjustment.

    But if you don't want to do that, then pick from any of the linear aftermarket lowering springs, just be careful on what rates you pick and how much lower the car is. Supra's need a lot of spring to keep the wheel where you want it, and with not enough, they will bottom out.

    Also, getting a 2.5" spring in the rate that you want, would allow you to better match the dampers valving. But I'm sure that's a lot for most people. On a side note, I am going to start offering a setup like this with off the shelf Bilsteins and Konis once I get the proper data.

    Tim

+ Reply to Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
Links monetized by VigLink