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DIRT69
12-10-2012, 05:54 PM
has anyone had much luck indexing the 4 links on the bird cages and if you do which ones do you move? one person says to do it and the other way says he nevers moves his?

Matt49
12-11-2012, 09:01 AM
has anyone had much luck indexing the 4 links on the bird cages and if you do which ones do you move? one person says to do it and the other way says he nevers moves his?

"Indexing" is the rotation of the birdcage on the axle. The angle and length of the links each have their own affect on how the birdcage will index.

MasterSbilt_Racer
12-11-2012, 10:08 AM
Some people call moving the links closer or farther from the axle "indexing". Which do you mean, DIRT69?

charcoal01
12-11-2012, 12:26 PM
Or are you talking about statically indexing the cage into or out of the cage?

4bangerhotrod
12-11-2012, 03:06 PM
we call indexing, moving the bar closer to the axle tube which index's the BC. we do it some in qualifying on LRT when we need the car to stay about the same but need alittle more traction off and it help's free the car in alittle bit. it will help get the car on the bar's alittle quicker and because your speeding up the BC rotation. it that what your talking about or are you talking about shorting top rod and lengthening the bottom rod

DIRT69
12-11-2012, 09:29 PM
i was talking about indexing it on the birdcage. like dropping the top rods on the bird cage or raising the bottom rods on the bird cage. i heard about running a 6/7 inch dop mount on LR shocks for the slick and something about a 2 inch drop mount for the rr ??

4bangerhotrod
12-11-2012, 11:43 PM
i dont understand what your talking about a 6/7in drop mount on your shock and a 2 in drop mount on rr shock. why would you need a 6"-7" drop mount for your LR an a 2" for your RR and what would that have to do with indexing?

MasterSbilt_Racer
12-12-2012, 07:53 AM
Shock drop (distance from axle centerline to birdcage shock mount) and indexing as you describe it, can be tuning tools. Indexing is a powerful adjustment and you better understand what it will do before you do it.

jason29a
12-12-2012, 03:33 PM
Shock drop (distance from axle centerline to birdcage shock mount) and indexing as you describe it, can be tuning tools. Indexing is a powerful adjustment and you better understand what it will do before you do it.

Ok help the guy out. If understood it he wouldnt have asked the question.

MasterSbilt_Racer
12-12-2012, 04:15 PM
Ok help the guy out. If understood it he wouldnt have asked the question.

He asked if it worked and which ones to move. I can find reasons to move all 4 of them. I didn't really have the time or desire to describe the process for each one.

Moving a bar closer to the axle puts more thrust load in the bar.

Moving a bar closer to the axle makes that bar's effect on birdcage rotation more pronounced.

Example: Lowering lru on cage will increase loading on the bar, angle of the bar, and birdcage index into spring during chassis hike. All of these lead to increased lr wheel weight. The increased bar angle and birdcage rotation will also lead to additional roll steer.

lm17g
12-13-2012, 06:22 AM
iam woundering what degree the birdgages should be set at our set up book doesnt say what the angle should be just that you have to lenghthen top and shorten bottom or vice versa to change or is there a web site or book i could read up on it thanks

jedclampit
12-13-2012, 09:15 PM
Never had much success with the lowers, but never put alot of time into working around the bad tendencies I noticed. The uppers I have done on both sides as handling required. Dropping the rr on the cage will really help loosen up a tight car, from the center out.The lr can go either way.

but generally any time you add angle upward toward front of car to a 4 link rod you add drive to the closest tire and more loose steer overall, sometimes one outweighs the other(drive vs steer) in handling change (usually lr index) or compliments the handling change(rr index).

jedclampit
12-13-2012, 09:28 PM
iam woundering what degree the birdgages should be set at our set up book doesnt say what the angle should be just that you have to lenghthen top and shorten bottom or vice versa to change or is there a web site or book i could read up on it thanks

Generally.......... you set the link rods to a predetermined length in a baseline set of mounting points on the frame and that will clock the cage straight up and down, at the correct ride heights.The lr may be rolled forward a bit at the top with higher bite setups.

There are variances in every car built for sure!!!(and they seem to be getting worse not better) ... there is a way to clock the cages perfectly,but I don't have time to peck it out on a keyboard!

And is not going to make a huge difference unless they are way off.