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  1. #1
    Join Date
    Nov 2014
    Location
    South Carolina
    Posts
    54

    Default Too much TRACTION!

    This may sound silly but I'm having a problem with too much traction. We are very fast at our bull ring tracks. We qualify on the pole and run top 3 at all different tracks. But we have a few tracks around that are very fast momentum tracks with minimal throttle lift during qualifying. Went Saturday and didn't lift for both qualifying laps. The car is bogging very bad on exit, we have tried everything but for every positive we do for exit its a negative for entry and center. We are currently at a 425 LF spring, 325 RF spring, 200 LR, 250 RR, with a 250 5th at 35". The J-bar is 9" on frame and ½" above center of pinion. We have 53.4% L/S and 52.9% rear with 107 pounds of bite. Also when the track starts slicking off and taking rubber it starts picking the LF up and hunkering down on RR. All bars are standard except the left bottom and its one up, this is a 2008 Mastersbilt Smack down. Any and all help will be appreciated!

  2. #2
    Join Date
    Jun 2007
    Posts
    3,123

    Default

    Quote Originally Posted by TLM4t4 View Post
    This may sound silly but I'm having a problem with too much traction. We are very fast at our bull ring tracks. We qualify on the pole and run top 3 at all different tracks. But we have a few tracks around that are very fast momentum tracks with minimal throttle lift during qualifying. Went Saturday and didn't lift for both qualifying laps. The car is bogging very bad on exit, we have tried everything but for every positive we do for exit its a negative for entry and center. We are currently at a 425 LF spring, 325 RF spring, 200 LR, 250 RR, with a 250 5th at 35". The J-bar is 9" on frame and ½" above center of pinion. We have 53.4% L/S and 52.9% rear with 107 pounds of bite. Also when the track starts slicking off and taking rubber it starts picking the LF up and hunkering down on RR. All bars are standard except the left bottom and its one up, this is a 2008 Mastersbilt Smack down. Any and all help will be appreciated!
    Less bite and maybe go up on the top right bar so the car will turn better on the gas.
    If you're on the gas entering the corner like you describe, take everything anybody has told you about changing handling on corner entry and scrap it. Think more in terms of making changes that would normally be thought of as corner exit adjustments even for corner entry.
    If you're truly on a momentum deal track, see about getting your RF shock rebound pretty stiff to keep it buried (but not bottomed out) all the way around the track. This will also help the car turn while on the gas because it decreases dynamic wedge while on the gas.

  3. #3
    Join Date
    Nov 2014
    Location
    South Carolina
    Posts
    54

    Default

    Thanks for the Matt49, I really don't need the car to turn anymore I just need to lose traction. I like your suggestion with the RF. I know there's quit a few guys running around here with a 250 spring on RF. Could I soften the RF, add rebound, and take some j-bar angle out? Most people are running center of pinion or 1 below, we are 1 above center with all of our lead down low. I'm really stumped here!

  4. #4
    Join Date
    Jun 2007
    Posts
    3,123

    Default

    Quote Originally Posted by TLM4t4 View Post
    Thanks for the Matt49, I really don't need the car to turn anymore I just need to lose traction. I like your suggestion with the RF. I know there's quit a few guys running around here with a 250 spring on RF. Could I soften the RF, add rebound, and take some j-bar angle out? Most people are running center of pinion or 1 below, we are 1 above center with all of our lead down low. I'm really stumped here!
    Then I guess I'm confused on what you mean by "too much traction". I took that to mean that you had too much LR drive on the throttle (what most people refer to as forward bite) not allowing the car to turn. What is the actual handling condition you're trying to fix?

  5. #5
    Join Date
    May 2009
    Posts
    1,336

    Default

    How much are you traveling 5th? Could you use the traction you have if you delayed when the traction comes in?

  6. #6
    Join Date
    May 2015
    Posts
    856

    Default

    I think ur too soft and or long on 5th coil. I experienced the same thing on blue Rocket. We went from a 300@36" to a 250@38" and picked up WAY too much drive. I would try a 300 in the same hole and then move it back if that wasn't enough.

  7. #7
    Join Date
    Feb 2008
    Location
    Illinois
    Posts
    3,734

    Default

    Never too much traction, just not enough horsepower. Gear change for a start. If that don't work, more cubic inches. Why do you think they run them monster 500 inch motors or turn up the RPM at places like Knoxville or Eldora. You can hear them grunt. There can be some disadvantages to overpowering a track, but can anyone see any advantage to under power one? This is why some carry up to 4 different power packages. This is why some stay off so called big motor breaker tracks.

    The good thing is your doing a lot of things right.
    Last edited by Bubstr; 05-11-2015 at 05:21 PM.

  8. #8
    Join Date
    Jul 2009
    Posts
    1,380

    Default

    don't know what engine combo your running but there have been several times that we have run a lot more gear than most just because we were tractioned up so much,im just guessing here but this sounds like a crate car

  9. #9
    Join Date
    Nov 2014
    Location
    South Carolina
    Posts
    54

    Default

    It is a crate car, my super car is spot on. We have the j bar an inch higher on pinion than super plus different shock combination. I'm gonna agree on the 5th, I'm gonna put a 300 on at 35" which is standard. The 250 at standard works well with the open motor. As of now on the crate I'm getting around 3¼" of travel. What's puzzling me is when it tractions up it stays on the bars but it puts a squaring effect on the car laying it over on the RR and pulling the LF up on exit. Thinking about putting a 275 - 300 on RR to also try and hold that corner up better. But thanks for mentioning the 5th, come to think of it we softened it on the super car to try and stop blowing the tires off of it on exit.

  10. #10
    Join Date
    Nov 2014
    Location
    South Carolina
    Posts
    54

    Default

    Squating effect sorry!

  11. #11
    Join Date
    Mar 2011
    Posts
    3

    Default

    are you saying add gear takes traction away ?

  12. #12
    Join Date
    Apr 2015
    Posts
    234

    Default

    Not really takin away traction just changing where ur torque and horsepower come in. I have done this before an it does help

  13. #13
    Join Date
    Feb 2008
    Location
    Illinois
    Posts
    3,734

    Default

    If you have the traction, use the hey out of it. Drive it in harder, roll the center faster. More speed brings you farther into torque curve. If your flat footing it, higher numerical gear, will get you into torque curve farther. More RPMs = more HP. If you have the traction to use that HP, use it. Changing grooves can improve your corner speed at times and get you farther into the torque curve and have the wheel speed to take advantage of it. High side momentum. If the track is agreeable. Warning the end of straight a way RPM has a live or die number, dictated by you pocket book and how well built your engine is.

  14. #14
    Join Date
    May 2009
    Posts
    1,336

    Default

    But he said its a Crate Car.......

  15. #15
    Join Date
    May 2009
    Posts
    1,336

    Default

    You're running a crate with higher then normal bite if its a 604 or 602 on a RUBBERED UP race track which is its own animal. Which CRATE engine are you using 602, 604, 525? with your lack of HP are you sure its not you lugging the engine down instead of too much traction I mean its kind of the same kind of different. You're not over traveling the 5th by any means. Maybe you might want to think if you're running to much upper bar angle on both sides. You could have to much dynamic thrust for your motor and your track conditions. Maybe think about dropping both upper bars a hole.

  16. #16
    Join Date
    Nov 2014
    Location
    South Carolina
    Posts
    54

    Default

    I stiffened the 5th to a 300, also put a 300 on RR along with a super high rebound RF. Helped the car tremendously! Now I still have a tick too much traction. Car has a hopping effect on exit but I'm kind of leaning to putting a dummy on LR.

  17. #17
    Join Date
    Nov 2014
    Location
    South Carolina
    Posts
    54

    Default

    And its a 604, if I put more gear in it then it hits limiter or falls on its face. I can't drive the car any harder, flat footing it now. Thanks for all the help, we getting a lot closer!

  18. #18
    Join Date
    May 2007
    Location
    tulsa america
    Posts
    2,686

    Default

    how much slack in RR chain?

  19. #19
    Join Date
    Jul 2009
    Posts
    1,380

    Default

    Quote Originally Posted by TLM4t4 View Post
    I stiffened the 5th to a 300, also put a 300 on RR along with a super high rebound RF. Helped the car tremendously! Now I still have a tick too much traction. Car has a hopping effect on exit but I'm kind of leaning to putting a dummy on LR.
    shorten the lr chain limiter,but it will only take a little say a 1/4 inch,just remember if it gets super slick you need to let it back out,there is also alot of different areas to take away traction so its hard to say,i guess my question would be where does it have to much traction(I'm guessing off the corner and causing a push)you could lengthen the rr or more stagger,if the right side tires are in the track to hard you could go up on your left side%,just need to know where in the corner to help,if the rear tires are in the track to hard you could loose some rear weight,see what I'm saying there are alot of different ways to free up a car,if you have it that close you could try a 1" spacer on the rr as an easy adjustment that way when it slicks off you can take it back off
    Last edited by grt74; 05-20-2015 at 08:26 AM.

  20. #20
    Join Date
    May 2015
    Posts
    856

    Default

    On the Smack cars I worked on, we would start with a 300 in the second hole forward.When the track slicked off, we would put a 325 in the first hole.This is what the house car was doing at the time along with several other adj to tighten it up.As a crew chief, I never worked so hard between heats and feature, trying to get the car tight enough.There was a lot of time consuming adjustments.

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