Loose on entry, off the throttle

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  • Jmfosnaught
    Member
    • Jul 2007
    • 71

    #1

    Loose on entry, off the throttle

    2003 Black Front End Rocket w/steel block @ 2400 lbs.

    Springs

    LF-500
    RF-325
    LR-200
    RR-250

    Percentages

    Left-54.5 ish
    Rear-55

    130lbs of bite

    J-bar @ 8-1/4


    * I'm wondering if I need to drop the wedge?
  • MasterSbilt_Racer
    Senior Member
    • May 2007
    • 14324

    #2
    Originally posted by Jmfosnaught View Post
    2003 Black Front End Rocket w/steel block @ 2400 lbs.

    Springs

    LF-500
    RF-325
    LR-200
    RR-250

    Percentages

    Left-54.5 ish
    Rear-55

    130lbs of bite

    J-bar @ 8-1/4


    * I'm wondering if I need to drop the wedge?
    Having only a bit of knowledge about Rockets and assuming everything else is okay, I would increase the lf spring rate.
    Modern Day Spec Wedge Racing

    Comment

    • Matt49
      Senior Member
      • Jun 2007
      • 3123

      #3
      Dropping the wedge may help.
      I would first try lowering the bottom right bar on the chassis or a stiffer LF spring.
      If it is just a LITTLE loose on entry you could just try less compression in your RR shock.

      Comment

      • joedoozer
        Senior Member
        • Nov 2009
        • 745

        #4
        Every driver/car/track is different. But if it were me/my car/our track I would drop the bite to 75 and see what it does. Left side % is a little high too. But again that's me.
        Crew Chief "Tip of the day":
        Most handling problems can be solved by adjusting the screw-ball. It can be difficult to fine tune at times. Explaining yourself loudly and striking it on top of the helmet with a dead blow hammer usually works well.

        Comment

        • jedclampit
          Senior Member
          • Mar 2008
          • 613

          #5
          Your scale # would be helpful & 4 bar locations.# of holes also.
          What are track conditions when this loose entry is happening?

          With what I know about your deal so far.....
          take 250 out of rr and put a 225 there........... I know, just do it!
          raise j bar to 8 3/4"-9 1/4 " @ frame,

          where is ph bar it compared to pinion centerline?

          325 is pretty soft , is it bottoming ?
          if its a small flat track you MAY get away with a 325.

          2400 # car with steel block, how much and where is the ballast?

          sounds like the car is not compressing the rr, a 250 in the rr can be too much to get the transfer to start, you'll know if you lower the rr lower rod and it gets looser in!

          depending on the track/conditions, a 375 is a good place to start with the rf spring

          big indicator on where to go will be travel on both right side shocks

          Comment

          • Jmfosnaught
            Member
            • Jul 2007
            • 71

            #6
            Originally posted by jedclampit View Post
            Your scale # would be helpful & 4 bar locations.# of holes also.
            What are track conditions when this loose entry is happening?

            With what I know about your deal so far.....
            take 250 out of rr and put a 225 there........... I know, just do it!
            raise j bar to 8 3/4"-9 1/4 " @ frame,

            where is ph bar it compared to pinion centerline?

            325 is pretty soft , is it bottoming ?
            if its a small flat track you MAY get away with a 325.

            2400 # car with steel block, how much and where is the ballast?

            sounds like the car is not compressing the rr, a 250 in the rr can be too much to get the transfer to start, you'll know if you lower the rr lower rod and it gets looser in!

            depending on the track/conditions, a 375 is a good place to start with the rf spring

            big indicator on where to go will be travel on both right side shocks

            Don't have the exact scale numbers in front of me at the moment, but they look something like this:

            LF-598
            RF-499
            LR-749
            RR-619
            Total weight is actually 2465

            Driver weighs 235 lbs, which is the reason for the higher left side percentage. 20 gallons of fuel and 60 lbs. of ballast directly in front of fuel cell to achieve rear percentage. No other ballast in the car.

            Track conditions are semi slick to slick and this is happening at various tracks. All are 1/4 mile to 4/10 mile in size. There are different degrees of banking at the 3 separate tracks. We are also encountering a push, on the throttle, especially when it's tackier. I'm hoping that fixing the corner entry will help with the exit.

            We're using a 12 inch, 325 lbs. spring on the RF with no sign of it bottoming out. All tracks go from semi tacky to slick as the night goes on.

            J-bar is mounted in the lowest hole on the rearend side, which is about an inch below the pinion centerline?

            4 link bars are as follows:

            LRT is in the second of three holes, at times we index down on the birdcage 1/2" to 1"

            LRB is usually in the third of five holes, we don't move this much (but have used the second hole up at times)

            RRT is in the bottom of three holes

            RRB is in the middle of three holes

            Comment

            • JOKER22
              Junior Member
              • Jun 2011
              • 8

              #7
              I would move jbar to 1 hole below pinion, and move right bottom bar down 1 hole, jmo

              Comment

              • jedclampit
                Senior Member
                • Mar 2008
                • 613

                #8
                Do you bottom out the coilover, a zip tie on shaft should show you whats going on there, if crushed, your bottoming, 12" spring should not coilbind.

                You shure its not too tight and your sliding it to turn it when its slick?

                What is the attitude of the car as it goes thru corner?
                Up on bars, down all the way fast when out of gas , toting the lf etc.

                Comment

                • Jmfosnaught
                  Member
                  • Jul 2007
                  • 71

                  #9
                  Originally posted by jedclampit View Post
                  Do you bottom out the coilover, a zip tie on shaft should show you whats going on there, if crushed, your bottoming, 12" spring should not coilbind.

                  You shure its not too tight and your sliding it to turn it when its slick?

                  What is the attitude of the car as it goes thru corner?
                  Up on bars, down all the way fast when out of gas , toting the lf etc.
                  I'm going to check the RF shock travel tonight.

                  I'm braking in a straight line, I don't think I'm sliding the rear to make it turn.

                  Once I can pick up the throttle, the car drives off the corner just a little snug...when it's slick. It feels like its picking up the LF slightly, while on the throttle, off the corner. Also, It's more of a push, off the corner, when it's tacky. It doesn't seem like it gets up on the bars getting into the corner.

                  Comment

                  • jedclampit
                    Senior Member
                    • Mar 2008
                    • 613

                    #10
                    for exit push with grip:
                    raising rrt up one hole when its tacky should help exit push,if its still pushy lower lr upper 1 hole,


                    for the loose in problem when slick,
                    does your car drop down the lr suddenly when you lift?

                    what are you using/doing with shocks thru night?
                    how is your lr travel limited (lr front shock or chain,etc)?
                    how much drop in lr suspension?

                    Comment

                    • powerslide
                      Senior Member
                      • May 2007
                      • 2696

                      #11
                      i think the simple answer is stay in the gas. If you watch richards and the big guys in the rockets they all trail brake pretty hard rarely lifting, even if someone is beside them. If your driver hasnt tried it, it is a good way to fix problems on entry once on the track.

                      Comment

                      • joedoozer
                        Senior Member
                        • Nov 2009
                        • 745

                        #12
                        Originally posted by powerslide View Post
                        i think the simple answer is stay in the gas. If you watch richards and the big guys in the rockets they all trail brake pretty hard rarely lifting, even if someone is beside them. If your driver hasnt tried it, it is a good way to fix problems on entry once on the track.
                        I have done this before. It's great when it works. But miss your mark or have to get out of the throttle once you are in the middle of the corner. And a WOOHOO moment turns into an OH SH!T moment real quick. lol
                        Crew Chief "Tip of the day":
                        Most handling problems can be solved by adjusting the screw-ball. It can be difficult to fine tune at times. Explaining yourself loudly and striking it on top of the helmet with a dead blow hammer usually works well.

                        Comment

                        • Jmfosnaught
                          Member
                          • Jul 2007
                          • 71

                          #13
                          RF shock has about 1" of travel left, it is not bottoming out.

                          Comment

                          • drtrkr244
                            Banned
                            • Dec 2007
                            • 1024

                            #14
                            If its a little loose, increase gas pressure in LF 25-50lbs.

                            Otherwise, increase LF sring, raise j bar on frame, or lower RR botom rod 2 holes.(if their .5 inch)

                            Comment

                            • 4bangerhotrod
                              Senior Member
                              • Dec 2008
                              • 374

                              #15
                              if your just alittle loose on entry raise your LF spring to a 550lb or 600lb spring. start with the 550 lb spring and if you need more the go to the 600lb. you could try putting rounds just in your LR if the car doesnt feel like its rolling over good this just helps the car get started easier, according to which shocks you have 8 turns or 16 turns per inch try droping the coil over adjuster down about an inch on LR only. and you said it's a steel block, is the engine raised up an inch.
                              thanks,
                              4bangerhotrod

                              Comment

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