Birdcage bar positions

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • hunterracing
    Senior Member
    • Jan 2009
    • 303

    #1

    Birdcage bar positions

    What would affects be if you took little angle outa top bar but then lowered it equally down on cage and frame to lowest hole on cage then took the lrl and lowered it to 5.5 on cage and lowest hole on frame keeping same angle would this give more drive and maybe take some steer out as well?
  • Kromulous
    Senior Member
    • May 2007
    • 3008

    #2
    Speaking on the LR? you asked this before and i can relay a few findings. Now a disclaimer, this is on a Mod, but i found it about the same.

    The RR i raised the top bar to 5" and the lower at standard 4.5", the car laid over bad on the RR. Same bar angles, i set it back to 4.5" on the upper bar and the attitude was better. May be a great adjustment when its super slow and slick.

    LR, lower bar to 5.5" on a zero index deal, actually it indexes a little so... Anyway, same angles on the bar, just lowered it on both ends. It makes a lot of drive, and really promotes the hike. We're running around 300lbs of droop load.

    Once i moved the LR bar, car really made the drive we needed. I would be careful on a SLM, track would have to be somewhat slicked off or you might just shove the nose all over the track. This has been one of the biggest impacts to the car, really changed how the car drove.

    Also one of the biggest changes i have seen is a 3" bar length split on the RR, really deadens the drive and makes it lay over and calm. The indexing change really helped.

    Hope the helps. We race on dry slick pretty much all the time, Hot Laps you get some wet but thats about it.

    Also this was all with the same springs, shocks and stagger.

    Just say no...

    Comment

    • hunterracing
      Senior Member
      • Jan 2009
      • 303

      #3
      That makes sense

      Comment

      • pa_dirt
        Senior Member
        • May 2007
        • 259

        #4
        Originally posted by Kromulous View Post
        Speaking on the LR? you asked this before and i can relay a few findings. Now a disclaimer, this is on a Mod, but i found it about the same.

        The RR i raised the top bar to 5" and the lower at standard 4.5", the car laid over bad on the RR. Same bar angles, i set it back to 4.5" on the upper bar and the attitude was better. May be a great adjustment when its super slow and slick.

        LR, lower bar to 5.5" on a zero index deal, actually it indexes a little so... Anyway, same angles on the bar, just lowered it on both ends. It makes a lot of drive, and really promotes the hike. We're running around 300lbs of droop load.

        Once i moved the LR bar, car really made the drive we needed. I would be careful on a SLM, track would have to be somewhat slicked off or you might just shove the nose all over the track. This has been one of the biggest impacts to the car, really changed how the car drove.

        Also one of the biggest changes i have seen is a 3" bar length split on the RR, really deadens the drive and makes it lay over and calm. The indexing change really helped.

        Hope the helps. We race on dry slick pretty much all the time, Hot Laps you get some wet but thats about it.

        Also this was all with the same springs, shocks and stagger.
        What do you mean by the 3” rod split? We are struggling with forward bite as well.

        Comment

        • Kromulous
          Senior Member
          • May 2007
          • 3008

          #5
          Bar lengths, lower is 15" and upper is 18". That is on the RR.

          On my car, LR, with the zero index deal, i have to run a 18" upper, and a 14 3/4" lower, and it has welded in plates (SMH) Does anyone think there is more traction to be had with a shorter upper bar? Thinking about making a shortening bracket like what Rocket used to have on there cars and going to like a 16 1/2 or so.

          Just say no...

          Comment

          • hunterracing
            Senior Member
            • Jan 2009
            • 303

            #6
            That’s a big split on lr would think it would rollsteer a bunch

            Comment

            • Jking24
              Senior Member
              • Oct 2017
              • 1512

              #7
              15 and 18 is pretty standard in the right side. I think some of the older mb stuff would run somthing like a 13-14" lower at times iirc

              Comment

              • brett4
                Member
                • Sep 2010
                • 88

                #8
                Kromulous, what LR spring are you running with 300lbs of droop load?? what kind of lower bar angle are you running on lower left when the car is on the ground??? is this a UMP mod

                Comment

                • Kromulous
                  Senior Member
                  • May 2007
                  • 3008

                  #9
                  I run a 100lb spring, i like to be able to measure it on the fly so the 100 is easy to add up LOL. Some run the 80, i dont think there is any difference. On the Mod with the slider its a pain to pull it off and smash it, so i just measure the compressed spring and multiply it to the spring rate.

                  So at full droop my spring measures 17" on a 20" spring, is it exactly 300? probably not, but its close.

                  Lower bar is 10 degrees, or so. I will have to measure it on the ground, that is a estimate.

                  Yes, UMP Mod, so your mileage might very with a SLM, but i was trying to relay some info to Hunter racing, he and i asked before about the bar position on the cage, and not a lot of intel was out there on it.

                  Just say no...

                  Comment

                  • Jking24
                    Senior Member
                    • Oct 2017
                    • 1512

                    #10
                    Originally posted by Kromulous View Post
                    I run a 100lb spring, i like to be able to measure it on the fly so the 100 is easy to add up LOL. Some run the 80, i dont think there is any difference. On the Mod with the slider its a pain to pull it off and smash it, so i just measure the compressed spring and multiply it to the spring rate. So at full droop my spring measures 17" on a 20" spring, is it exactly 300? probably not, but its close. Lower bar is 10 degrees, or so. I will have to measure it on the ground, that is a estimate. Yes, UMP Mod, so your mileage might very with a SLM, but i was trying to relay some info to Hunter racing, he and i asked before about the bar position on the cage, and not a lot of intel was out there on it.
                    Just a little fruit for thought always wanna measure the free standing height of the spring off the car. Most manufactures are pretty good about this now days but not so long ago I've seen free standing heights vary over+- 3/8". secondly the first inch is usually soft so maybe 90# on a 100# but then you couple that with the variance in height you could be off nearly 40# either way. So it is entirely possible that your 300# could be 340 or 250. I'm not insinuating you don't already know this krom just thought it was info worth mentioning

                    Comment

                    • Kromulous
                      Senior Member
                      • May 2007
                      • 3008

                      #11
                      Ive seen some really collapse, but i run Eibach pretty exclusively, and not seen them move much. Usually i will throw them on the smasher a couple times thru the year and check too.

                      Next year i am going to put jack bolt on the LR upper shock mount, so i can unwind it, should make it a lot easier to get on and off the car. That or get one of them Advance Preloader deals, them look pretty sweet.

                      Just say no...

                      Comment

                      • Jking24
                        Senior Member
                        • Oct 2017
                        • 1512

                        #12
                        Eibach springs are super consistent a freind of mine mic'd them and across like six or seven springs they were within. .012" and they come preset so that shouldn't change unless the sorting incurs damage

                        Comment

                        • JustAddDirt
                          Senior Member
                          • May 2007
                          • 1893

                          #13
                          Originally posted by Kromulous View Post
                          Ive seen some really collapse, but i run Eibach pretty exclusively, and not seen them move much. Usually i will throw them on the smasher a couple times thru the year and check too.

                          Next year i am going to put jack bolt on the LR upper shock mount, so i can unwind it, should make it a lot easier to get on and off the car. That or get one of them Advance Preloader deals, them look pretty sweet.
                          Do that with the LR shock, and the eliminator mount.
                          That way you don't have to have shock extensions if a quick shock change is needed. Or you switch brands, lengths vary.
                          I think there should be lifeguards in the genepool.

                          Comment

                          • Kromulous
                            Senior Member
                            • May 2007
                            • 3008

                            #14
                            JAD, were you on a shock in the front, slider in back, or coil over on the LR? We tried a coil over and just cant keep the car up.

                            This car is weird, its has the front shock on a jack bolt deal, and the back hard mounted. I guess they dont want you messing with the spring base, but seriously. That and welded in 4 bar plates, and these front shock mounts are sad.

                            Im gonna retire someday, and build my own cars, my way LOL. Come on lotto !

                            Just say no...

                            Comment

                            • MachineMasters
                              Member
                              • Oct 2010
                              • 74

                              #15
                              Originally posted by Kromulous View Post
                              JAD, were you on a shock in the front, slider in back, or coil over on the LR? We tried a coil over and just cant keep the car up.
                              I'd bump your LR coilover compression valving up so it has 300lbs of compression at 2" per second. Keeps LR up and lets you drive like you had a shock in front.

                              Comment

                              Working...
                              X