Motor Height and front springs

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • LateModel B23
    Senior Member
    • Oct 2012
    • 283

    #1

    Motor Height and front springs

    Working with a car that has motor raised 2", chassis book calls for 550's across the front. With all the physics, geometry and such that is always discussed - are the 550's still good? Afterall several hundred pounds has been moved higher which should affect the transfer - maybe?
  • Confused?
    Senior Member
    • Apr 2009
    • 418

    #2
    It depends on the front geometry. They could be perfect or way too soft. Have you driven the car like it is yet? Try it. Then change as needed.
    Bill W. and Dr. Bob......who could have known.

    Comment

    • LateModel B23
      Senior Member
      • Oct 2012
      • 283

      #3
      Raced it Saturday night for the first time with the 550's. Driver is someone who I have worked with for close to 10 years driving a late model for me - when I still owned late models. He felt like it was going onto the RF too much, almost to the point of taking LR drive out. It was also his first time back in a 4 bar car in right at 2 years.

      This is a Chevelle stub 4 bar car.

      Comment

      • Bcollins82
        Senior Member
        • Jul 2009
        • 322

        #4
        How much LR drop do you have? Sounds like you may need more?

        Comment

        • LateModel B23
          Senior Member
          • Oct 2012
          • 283

          #5
          LR is set per book - 19 5/8" chain length and LR shock is then adjusted accordingly. This is a Skyrocket.

          Comment

          • Confused?
            Senior Member
            • Apr 2009
            • 418

            #6
            Raising the motor is generally used for an extremely dry track. It helps with slower speed weight transfer. Remember, the book is only a base guideline. Adjust as needed. If you feel that's its too hard on the rf, up the spring or change the upper ball joint.
            Bill W. and Dr. Bob......who could have known.

            Comment

            • Confused?
              Senior Member
              • Apr 2009
              • 418

              #7
              If the car was set up for an aluminum headed motor and you are running iron heads, you should probably drop the motor back down.
              Bill W. and Dr. Bob......who could have known.

              Comment

              • LateModel B23
                Senior Member
                • Oct 2012
                • 283

                #8
                It is a USRA spec aluminum head motor.

                Comment

                • drtrkr244
                  Banned
                  • Dec 2007
                  • 1024

                  #9
                  Try adding more lf rebound and/or more rf compression to slow down the weight transfer. Give it a couple of races to get your driver acclimated to it, before you give up on it. If ur not bottoming out rf shock it should be ok.
                  Last edited by drtrkr244; 10-06-2014, 07:12 PM.

                  Comment

                  • save the racers
                    Senior Member
                    • May 2013
                    • 271

                    #10
                    Ive never seen one moved up 2inches that seems pretty extreme. I would cut it down to about an inch above standard. I would be looking elsewhere if i thought i needed to raise the motor 2inches. Unless they just had a god awful large pan they couldnt get clearence for i cant see raising it that high.

                    Comment

                    • DirtRacer9x
                      Senior Member
                      • Jul 2014
                      • 305

                      #11
                      I've seen 1.5" and 2" on a couple imca champs running crates. One was a jet car the other was a hole built chassis.

                      Comment

                      • old dirt racer
                        Junior Member
                        • Nov 2010
                        • 8

                        #12
                        When you say raise an engine 2" that would be 2" from where. What is the baseline? OEM hieght or minimun in the rule book?

                        Comment

                        • LateModel B23
                          Senior Member
                          • Oct 2012
                          • 283

                          #13
                          Raised 2" from where the car builder - Skyrocket - originally had the mounts.

                          Comment

                          • old dirt racer
                            Junior Member
                            • Nov 2010
                            • 8

                            #14
                            I am just returning to racing after an 18 years vacation. One thing that I remember is that car builders differed in engine hights and to compair one to the other you need to measure from the cranckshaft center to the ground as allthings relating to the center of gravity (cg) must reference to the ground and the roll centers be the same on both cars to compair cg differences that affect sidebite.

                            Comment

                            • RW57
                              Senior Member
                              • Dec 2007
                              • 662

                              #15
                              We moved the engine to the right about 2.5 to 3 in on my sons stock clip late model but did not raise motor the difference it made as far as getting on rf was unreal we have a1000 on rf 1100 on lf I think we are going to have to going to have to go back up on rf as I think it is going over to far on rf .It is not bottoming out though I was told if it ain't bottoming out it its not over too far but I ain't convinced of that.

                              Comment

                              Working...
                              X