what is the benefit of running zero index birdcage plates?
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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.
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 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.
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.
I guess it cant hurt to ask, but would you comment on your LF and LR Droop changes? What impact etc.
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
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 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.......
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.
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.
@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?
Thanks. Now you have me thinking... :)