Soft Spring Frustration

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  • Denali_2017
    Junior Member
    • Jul 2020
    • 9

    #1

    Soft Spring Frustration

    So first off I've been reading through this forum for quite some time and man there is so much good info on here!! So here goes my first post. I know there's alot of people who say you don't need a 20" LR spring but I need some info. While running a 20" 100lb spring with a chain limiter when you jack the car and have it on the limiter and that 20" spring is compressed to 16.5" is your droop load 3.5" x 100lbs = 350lbs of droop/pre load? And if so does this number effect what you dial in for left rear bite static on the scales?
  • MasterSbilt_Racer
    Senior Member
    • May 2007
    • 14304

    #2
    Originally posted by Denali_2017 View Post
    So first off I've been reading through this forum for quite some time and man there is so much good info on here!! So here goes my first post. I know there's alot of people who say you don't need a 20" LR spring but I need some info. While running a 20" 100lb spring with a chain limiter when you jack the car and have it on the limiter and that 20" spring is compressed to 16.5" is your droop load 3.5" x 100lbs = 350lbs of droop/pre load? And if so does this number effect what you dial in for left rear bite static on the scales?
    Yes, your droop load is 350#. LR static bite on the scales doesn't mean much except maybe on a restart for a fraction of a second.

    The only way to make both of those loads what you want is to adjust chain length or select the correct spring.
    Modern Day Spec Wedge Racing

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    • Denali_2017
      Junior Member
      • Jul 2020
      • 9

      #3
      Thank you for responding so fast. I know it's a gm 4 arm triangulated mess back there but we have had great results with those numbers until recent when it's been hot and tracks slicks off. We had been lightning fast running around on the top but the last 2 nights it's been a bottom race track and we are lacking something down there. Been running 150lbs of static LR with that 350# load number. Do I need to open up the chain to let the car roll up more to run the bottom? Again appreciate your response

      Comment

      • MasterSbilt_Racer
        Senior Member
        • May 2007
        • 14304

        #4
        Originally posted by Denali_2017 View Post
        Thank you for responding so fast. I know it's a gm 4 arm triangulated mess back there but we have had great results with those numbers until recent when it's been hot and tracks slicks off. We had been lightning fast running around on the top but the last 2 nights it's been a bottom race track and we are lacking something down there. Been running 150lbs of static LR with that 350# load number. Do I need to open up the chain to let the car roll up more to run the bottom? Again appreciate your response
        Is the car sliding up the track on entry?
        Modern Day Spec Wedge Racing

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        • Denali_2017
          Junior Member
          • Jul 2020
          • 9

          #5
          Car enters perfect wherever he wants to go. Says it's a little free getting in...center/off just doesent get up and go. Can hug the bottom all the way through no problem. Running a 850Rf with a tie down/Slow bleed and a 1000 bump spring. Soft spring is very new to us and we are still getting him use to it. Eventually want to start working down on the front spring rates as he gets comfortable

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          • MasterSbilt_Racer
            Senior Member
            • May 2007
            • 14304

            #6
            Originally posted by Denali_2017 View Post
            Car enters perfect wherever he wants to go. Says it's a little free getting in...center/off just doesent get up and go. Can hug the bottom all the way through no problem. Running a 850Rf with a tie down/Slow bleed and a 1000 bump spring. Soft spring is very new to us and we are still getting him use to it. Eventually want to start working down on the front spring rates as he gets comfortable
            More extended load will loosen off gas entry. More dynamic wedge will tighten exit. It sounds like you need more of that at the throttle application point. May need more bump spring engagement.

            Longer chain could help from load standpoint, but will introduce more steer.
            Last edited by MasterSbilt_Racer; 08-03-2020, 08:20 AM.
            Modern Day Spec Wedge Racing

            Comment

            • Denali_2017
              Junior Member
              • Jul 2020
              • 9

              #7
              So if I have 4" of droop with that #350 lb load on a 100lb 20" spring I'd want to stiffen the spring to get a little less load so it's not so free off throttle? And increase static wedge for exit . And soften RF to keep it on the bump? Increasing chain will lower load, increasing rear steer but could combat that with lower arm angle or lead the RR a little
              Last edited by Denali_2017; 08-03-2020, 08:27 AM.

              Comment

              • MasterSbilt_Racer
                Senior Member
                • May 2007
                • 14304

                #8
                Originally posted by Denali_2017 View Post
                So if I have 4" of droop with that #350 lb load on a 100lb 20" spring I'd want to stiffen the spring to get a little less load so it's not so free off throttle? And increase static wedge for exit . And soften RF to keep it on the bump?
                Question #1 You need less load at the attitude of corner entry. A stiffer spring would do what you say, if the LR corner is up at that point. If a stiffer spring changes the attitude, that goes out the window.

                Question #2 - I would soften main spring and raise the bump closer to engaging.
                Modern Day Spec Wedge Racing

                Comment

                • Denali_2017
                  Junior Member
                  • Jul 2020
                  • 9

                  #9
                  Ok these are some great things I can work on easily for this week. I appreciate you and your responses and will keep you posted on results

                  Comment

                  • MasterSbilt_Racer
                    Senior Member
                    • May 2007
                    • 14304

                    #10
                    Originally posted by Denali_2017 View Post
                    Ok these are some great things I can work on easily for this week. I appreciate you and your responses and will keep you posted on results
                    Sounds good. The rf spring change may do everything you need. I'd do just that first. I had a metric car in the 90s that was very fast with a 1000# rf. No bump or anything. So you are still not that soft, IMO.
                    Modern Day Spec Wedge Racing

                    Comment

                    • Denali_2017
                      Junior Member
                      • Jul 2020
                      • 9

                      #11
                      Yes everything we are working on has us headed to around 700 range. And I think with that bump spring we need to keep it buried longer so as I get him more comfortable and I get more understanding of it the better it will get. We aren't off much

                      Comment

                      • racer-15
                        Member
                        • Aug 2013
                        • 36

                        #12
                        Make sure the 20 inch spring isn't bowed. From what ive seen it works good for a few nights then spring bowes and car totally changes.

                        Comment

                        • racetech
                          Junior Member
                          • Aug 2012
                          • 3

                          #13
                          We have been out of the SS game for a few years and just got back into it this year. I remember our old car was flat with fairly stock rear trailing arm angles, We were fastest with an 1100 RF spring. Wow have things changed. We are running absurd rear bar angles on the lowers, and 80 lb 20 inch lr spring, an 800 RF with a bump, and we are still figuring things out. We had a 700 RF earlier this year and I cant say it was bad. Still working on the sticking the RR on entry it hasnt been good. We just had a practice session and upped the LF spring from 950 to 1100 and it was better, but it didnt get really good till we shimmed LF bump till we had about 3/8 inch of travel, it plants that RR now lol

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                          • JustAddDirt
                            Senior Member
                            • May 2007
                            • 1893

                            #14
                            triangulated 4 link on the GM cars do not work like a late models parallel 4 link.
                            i see people trying the soft RF spring deal, and they struggle.
                            the GM rear suspension binds up pretty bad, it may help if you have mono-balls in all the joints.
                            you are unloading and holding weight off the left rear corner of the car.
                            I just dont get it? maybe i am wrong.
                            I think there should be lifeguards in the genepool.

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