Page 1 of 3 123 LastLast
Results 1 to 20 of 47
  1. #1

    Default zero index birdcage

    what is the benefit of running zero index birdcage plates?

  2. #2
    Join Date
    Oct 2018
    Posts
    482

    Default

    Quote Originally Posted by brett4 View Post
    what is the benefit of running zero index birdcage plates?
    As you index, the suspension gets stiffer and stiffer until it is almost locked up. Remember when guys used to hit a hole on the straight and bounce 3 times? Fast cars don't do that now. Second reason, what goes up must come down. When it unindexes, the shock mount is moving away from the load as the car settles down on entry. The shock and spring is not holding the car up, as their job requires.

  3. #3
    Join Date
    May 2012
    Posts
    24

    Default

    Race engineer,
    Would mind sharing your thoughts on best amount of indexing if any on the right rear of most cars? I'm liking no indexing on LR. Do we need to index into or out of RR ? Or go with none and work with springs?
    Thanks

  4. #4
    Join Date
    Jul 2009
    Posts
    1,380

    Default

    Quote Originally Posted by DJ16 View Post
    Race engineer,
    Would mind sharing your thoughts on best amount of indexing if any on the right rear of most cars? I'm liking no indexing on LR. Do we need to index into or out of RR ? Or go with none and work with springs?
    Thanks
    if you don't want indexing, just bolt the bottom of the shock to the top of the tube, lr, i could see that working, rr you'll get beat by some sharp people, unless you carry several rr shock/spring setups

  5. #5
    Join Date
    Oct 2017
    Posts
    1,361

    Default

    I think people get a little too caught up in this "how we race now vs. The old school way. The bars still work just the same as they always did and the objective is still the same. Every thing is a give and take situation it may be good for one reason but bad in another way. If your not changing bar position then the index ratio is constant so no consistency loss or question marks marks their. It's also something that can easily be measured so it's not a "un known". The principal of smashing springs is not to eliminate all the geometry in the car but to be able to tune on it in a dynamic state where it is used most. Sorry i just don't understand alot of the ideology that comes up with "we don't race that way anymore" mindset

  6. #6
    Join Date
    Oct 2018
    Posts
    482

    Default

    Quote Originally Posted by Jking24 View Post
    I think people get a little too caught up in this "how we race now vs. The old school way. The bars still work just the same as they always did and the objective is still the same. Every thing is a give and take situation it may be good for one reason but bad in another way. If your not changing bar position then the index ratio is constant so no consistency loss or question marks marks their. It's also something that can easily be measured so it's not a "un known". The principal of smashing springs is not to eliminate all the geometry in the car but to be able to tune on it in a dynamic state where it is used most. Sorry i just don't understand alot of the ideology that comes up with "we don't race that way anymore" mindset
    The bars still work the same. We just know better than to put the LR top bar down to 3.5" from axle centerline now. A birdcage anywhere near cam over is a killer of speed. We also understand that unhike on corner entry kills corner speed. We now know that corner speed beats drag racing as well. 20 years ago, no one thought those things.
    Last edited by RaceEngineer; 06-24-2019 at 09:07 PM.

  7. #7
    Join Date
    Oct 2018
    Posts
    482

    Default

    Quote Originally Posted by DJ16 View Post
    Race engineer,
    Would mind sharing your thoughts on best amount of indexing if any on the right rear of most cars? I'm liking no indexing on LR. Do we need to index into or out of RR ? Or go with none and work with springs?
    Thanks
    I don't know that there is a best amount. You just need to get the dynamic load curve that works for you.

  8. #8
    Join Date
    Oct 2017
    Posts
    1,361

    Default

    Quote Originally Posted by RaceEngineer View Post
    The bars still work the same. We just know better than to put the LR top bar down to 3.5" from axle centerline now. A birdcage anywhere near cam over is a killer of speed. We also understand that unhike on corner entry kills corner speed. We now know that corner speed beats drag racing as well. 20 years ago, no one thought those things.
    i agree completely. This one just struck a nerve because while helping someone over the weekend with an older car. A bar change was suggested and the reply was not that he thought it didn't work that way but that it wouldn't have the desired effect because we don't race that way now so it wouldn't have the same effect.

  9. #9
    Join Date
    May 2007
    Posts
    796

    Default

    Quote Originally Posted by Jking24 View Post
    i agree completely. This one just struck a nerve because while helping someone over the weekend with an older car. A bar change was suggested and the reply was not that he thought it didn't work that way but that it wouldn't have the desired effect because we don't race that way now so it wouldn't have the same effect.
    My go to adjustment in 2014 and 2015 for a slick track feature was to crank turns into the LR and get a high bite number. That car was so good in the slick.

    If I try that now the car doesn't turn and I'd get lapped twice in a 25 lap feature.

  10. #10
    Join Date
    Jan 2012
    Posts
    332

    Default

    Quote Originally Posted by cjsracing View Post
    My go to adjustment in 2014 and 2015 for a slick track feature was to crank turns into the LR and get a high bite number. That car was so good in the slick.

    If I try that now the car doesn't turn and I'd get lapped twice in a 25 lap feature.
    Yea I used to be the same way. Now days all I mess with is LF droop, LR droop, packers, rear end lead, and spring rubbers. A lot less work that's for sure.

  11. #11
    Join Date
    May 2007
    Posts
    2,929

    Default

    I guess it cant hurt to ask, but would you comment on your LF and LR Droop changes? What impact etc.

    Just say no...

  12. #12
    Join Date
    Oct 2017
    Posts
    1,361

    Default

    I think a lot of you missed the point .I was referring specifically to a bar angle change. It still does the same thing that it always did. Some changes have less or minimal effect because of the fact that we maintain attitude better now and there is less movement in certain Corners than there used to be

  13. #13
    Join Date
    Oct 2017
    Posts
    1,361

    Default

    My main point was I see a lot of people outsmarting themselves chasing load numbers Etc the mechanics of the racecar haven't changed fundamentals of it are the same we just go about achieving what we need a different way now if you understand a lot of this stuff you can look back at your old setups and kind of start to understand why you had to do certain things because of what we know now and how those changes affected other corners

  14. #14
    Join Date
    Oct 2018
    Posts
    482

    Default

    Quote Originally Posted by Jking24 View Post
    My main point was I see a lot of people outsmarting themselves chasing load numbers Etc the mechanics of the racecar haven't changed fundamentals of it are the same we just go about achieving what we need a different way now if you understand a lot of this stuff you can look back at your old setups and kind of start to understand why you had to do certain things because of what we know now and how those changes affected other corners
    I agree with that 100%

  15. #15
    Join Date
    Dec 2008
    Location
    thedirtysouth
    Posts
    4,004

    Default

    i agree also jking , one thing i guess you could say theses " new " set ups has done is cause you to change or redesign the chassis , especially the front end.......

  16. #16
    Join Date
    Jan 2012
    Posts
    332

    Default

    Quote Originally Posted by Jking24 View Post
    My main point was I see a lot of people outsmarting themselves chasing load numbers Etc the mechanics of the racecar haven't changed fundamentals of it are the same we just go about achieving what we need a different way now if you understand a lot of this stuff you can look back at your old setups and kind of start to understand why you had to do certain things because of what we know now and how those changes affected other corners
    I hear what you're saying. I think we're all smarter than we used to be and take a piece to the track that is a little more dialed in than it used to be.

    I drop the LF out a little more if I need the RR to do a little more work in the center

    And i take LR droop out just to control roll steer a little better.

    I hadn't tried it til the guy I get info from tested with me once. I went from cranking wedge in a car and rolling the tool box out, to making small adjustments and not working near as hard. But that's why I source my info because I'm simply not smart enough nor do I have the time or resources to test or make educated guesses.

  17. #17
    Join Date
    May 2007
    Posts
    2,929

    Default

    Thanks King1, i was thinking along the same lines with LF and LR, but i always like to check my thoughts about what affects what.

    Anyway, i agree with the small adjustments. I am in the process of learning spring rubbers etc, and after sitting with my spring smasher and adding in and taking out rubbers and packers you can make some big changes, and with minimal work. After this last couple weeks where i dialed the car completely out, i am going to change my approach, to small adjustments etc.

    Just say no...

  18. #18
    Join Date
    Jun 2018
    Posts
    12

    Default

    @RaceEngineer. Why do you suppose a nearly cammed over birdcage kills speed? On the LR, the solution might be to raise the lower bar on the frame, or lengthen the lower, or index the birdcage back at ride height, to decrease upper bar angle at full droop. But what do those changes accomplish?

  19. #19
    Join Date
    Oct 2018
    Posts
    482

    Default

    Quote Originally Posted by Nesmith14b View Post
    @RaceEngineer. Why do you suppose a nearly cammed over birdcage kills speed? On the LR, the solution might be to raise the lower bar on the frame, or lengthen the lower, or index the birdcage back at ride height, to decrease upper bar angle at full droop. But what do those changes accomplish?
    The system has little to no compliance. The spring cannot function. The shock cannot function. That is bad for maintaining traction over bumps. You can rock the cage back to compensate.

  20. #20
    Join Date
    Jun 2018
    Posts
    12

    Default

    Thanks. Now you have me thinking...

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

All times are GMT -5. The time now is 05:35 AM.


Powered by vBulletin® Version 4.2.0
Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.