Too Tigh On Entry wont rotate

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  • Dirtracer18
    Junior Member
    • Aug 2014
    • 18

    #1

    Too Tigh On Entry wont rotate

    i have a 06 blue front end rocket with the wide rf. no matter what the track condition is the car will not rotate on entry it just plows the front end. LF 550 RF 275 LR 200 RR225 Left 54.4% Rear 51.8% Cross 54.4%. Scale numbers Lf 601 rf 602 LR760 rr 537Short ltb in the 3rd hole. Llb 4th hole. Rtb middle hole. Rlb 2nd hole. Bars are standard lengths for rocket. J bar is 9 3/4 on the frame and bottom of pinion been in the middle also still no difference. Running a steel headed motor
    Last edited by Dirtracer18; 11-07-2017, 12:25 PM.
  • 96racing
    Senior Member
    • Nov 2010
    • 112

    #2
    Where's the j bar? Mine acts that way when it doesn't have enough angle. Rear percentage seems quite low too.

    Comment

    • Dirtracer18
      Junior Member
      • Aug 2014
      • 18

      #3
      J bar is 9 3/4 on frame and in the bottom of the pinion

      Comment

      • MasterSbilt_Racer
        Senior Member
        • May 2007
        • 14303

        #4
        Any bump stops? Is the cross member still in the original place? You are likely bottoming out and that is why it pushes. Put a 400# in the rf, rescale, and see if it turns.
        Modern Day Spec Wedge Racing

        Comment

        • Dirtracer18
          Junior Member
          • Aug 2014
          • 18

          #5
          Yes have a bumpstop on the right front. Does not have a raised crossmember. I don't feel it bottom out. Haven't been on a 400 rf but have been on a 350 and 375.

          Comment

          • 7uptruckracer
            Senior Member
            • May 2009
            • 1336

            #6
            Originally posted by Dirtracer18 View Post
            i have a 06 blue front end rocket with the wide rf. no matter what the track condition is the car will not rotate on entry it just plows the front end. LF 550 RF 275 LR 200 RR225 Left 54.4% Rear 51.8% Cross 54.4%. Scale numbers Lf 601 rf 602 LR760 rr 537Short ltb in the 3rd hole. Llb 4th hole. Rtb middle hole. Rlb 2nd hole. Bars are standard lengths for rocket. J bar is 9 3/4 on the frame and bottom of pinion been in the middle also still no difference. Running a steel headed motor
            You have 223lbs of LR Bite. That’s needs to be around 120. All that bite if you are driving in on the far that’s gonna make it push. 450 Left Front spring, 325 RF. 8 3/4 jbar middle pinion, 53.5 rear, reset all your front end and get rid of the short LRU just as basics

            Comment

            • CCHIEF
              Senior Member
              • Jul 2014
              • 399

              #7
              Rear too light panhard bar too high @ frame rf spring too soft rr way to light...too much bite get back to a normal loose baseline with correct %...you need some lead toward the rr

              Comment

              • Aggressor
                Member
                • Dec 2009
                • 62

                #8
                go to a 250 rr

                Comment

                • JustAddDirt
                  Senior Member
                  • May 2007
                  • 1893

                  #9
                  Originally posted by Aggressor View Post
                  go to a 250 rr
                  That will tighten entry
                  I think there should be lifeguards in the genepool.

                  Comment

                  • billetbirdcage
                    Senior Member
                    • May 2007
                    • 2019

                    #10
                    Originally posted by JustAddDirt View Post
                    That will tighten entry
                    Up to about 2 years ago, I'd whole heartily agree with that but now: There are exceptions to that and quite a few actually.

                    1 If you're only changing the spring and maybe resetting the coilover back to the same ride hieght, then yes most of the time that's what you're going to get.

                    2. However if your changing the spring and adjusting the ride height load number, then you may not get the same effect. Meaning I have a 225# spring with a static ride hieght load number of say 350# and typically traveling 2.5" from ride height. So that makes my static load 350# and my 2.5" load at 912.5, but say I do this: 250 spring with a 287.5# load number, my 2.5" number is the same 912.5#. I'll pretty much guarantee that it don't handle the same. I not only changed the ride hieght therefore right side bar angles and wheel base but also the aero on the car as well as the wedge numbers.

                    Like I'd said I'd agree with it for the most part but you have to take into context some of these other things because we are doing stuff completely different now and looking at things in other ways and it throws a bunch of exceptions into the old rules.

                    Just want to say I'd agree with justadddirt I probably wouldn't stiffen the spring in his case, but you have to know how he was going to change it. I'm going to go out on a limb and guess that I believe the OP is likely racing on a fairly flat track.
                    Last edited by billetbirdcage; 11-13-2017, 05:43 PM.

                    Comment

                    • a25rjr
                      Senior Member
                      • Feb 2016
                      • 3774

                      #11
                      Originally posted by billetbirdcage View Post
                      Up to about 2 years ago, I'd whole heartily agree with that but now: There are exceptions to that and quite a few actually.

                      1 If you're only changing the spring and maybe resetting the coilover back to the same ride hieght, then yes most of the time that's what you're going to get.

                      2. However if your changing the spring and adjusting the ride height load number, then you may not get the same effect. Meaning I have a 225# spring with a static ride hieght load number of say 350# and typically traveling 2.5" from ride height. So that makes my static load 350# and my 2.5" load at 912.5, but say I do this: 250 spring with a 287.5# load number, my 2.5" number is the same 912.5#. I'll pretty much guarantee that it don't handle the same. I not only changed the ride hieght therefore right side bar angles and wheel base but also the aero on the car as well as the wedge numbers.

                      Like I'd said I'd agree with it for the most part but you have to take into context some of these other things because we are doing stuff completely different now and looking at things in other ways and it throws a bunch of exceptions into the old rules.

                      Just want to say I'd agree with justadddirt I probably wouldn't stiffen the spring in his case, but you have to know how he was going to change it. I'm going to go out on a limb and guess that I believe the OP is likely racing on a fairly flat track.
                      Do you think most people re-set their ride heights after changing springs? I know that I never changed a spring at the track, that I had already tried it on the scales at the shop. Usually, I had a spare already set but not every time!
                      Turn LEFT, Vote RIGHT!

                      Comment

                      • billetbirdcage
                        Senior Member
                        • May 2007
                        • 2019

                        #12
                        Originally posted by a25rjr View Post
                        Do you think most people re-set their ride heights after changing springs? I know that I never changed a spring at the track, that I had already tried it on the scales at the shop. Usually, I had a spare already set but not every time!
                        Sure most do, but what I'm getting at it completely isn't the same thing.

                        My example above: 225 to 250 with resetting coilover nut (just for shear info here to adjust it back to the same ride height you are talking .150" of an adjustment up on the coil over nut to get it correct assuming both springs are indeed 225 and 250 and linear).

                        225 = #350 static load #912.5 dynamic
                        250 = #350 static load #975 dynamic

                        Mostly you changed the dynamic loads from ride height down and most likely lessened the travel on the RR.

                        If you did what I said with replacing the 225 with a 250 but altered the static load

                        250 = #287.5 static and #912.5 dynamic

                        I took some liberties here cause obviously these changes don't exactly mean the RR is still going to go to that imaginary 2.5" dynamic travel

                        All three of these are going to react differently which was the point I was making, the rate of the spring is only one factor. Again not saying anyone is wrong but depending on what you do, you are likely to get a different reaction.

                        Comment

                        • Matt49
                          Senior Member
                          • Jun 2007
                          • 3123

                          #13
                          Is there a particular scenario where I would actually want to change the RR spring and change the static load on that spring? Would the goal be just to free entry a little while maintaining the tightness from center off under full load? But then playing devil's advocate here...aren't there easier, simpler, or better ways to achieve that?

                          Comment

                          • MasterSbilt_Racer
                            Senior Member
                            • May 2007
                            • 14303

                            #14
                            Originally posted by Matt49 View Post
                            Is there a particular scenario where I would actually want to change the RR spring and change the static load on that spring? Would the goal be just to free entry a little while maintaining the tightness from center off under full load? But then playing devil's advocate here...aren't there easier, simpler, or better ways to achieve that?
                            Ask the XR1 guys who's RR corner keeps getting lower as the night goes on and they keep carrying spring rubbers to the rr.
                            Modern Day Spec Wedge Racing

                            Comment

                            • 7uptruckracer
                              Senior Member
                              • May 2009
                              • 1336

                              #15
                              I don't personally know anyone on XR1 who are changing things there anymore, the other Rockets definitely though. I dunno what the difference is on why one and not the other. My friends running and winning on XR1 still aren't chanfing anything bc Rocket told them not too lol. Now that being said the only change I was told was recommended was being told to take rounds out the RR as an adjustment. That and the stagger. Which Maybe another topic for discussion the low stagger makes alot more sense for driving a car straight ahead then the 4" we have always just stuck with

                              Comment

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