Wheel hop....isn't getting better either. :(

[LS6 Tommy]

So the angle of the arms intersecting, no mater where they originate, don't change the instant center? If that's the case the anti hop bars don't recreate instant center either right?

Alex.

The angle of the mounting points is what makes the difference. The way you modified the arms doesn't change the angle of the mounting points, just the angle of the arms themselves. Anti hop bars raise the axle end mounting points.

Tommy

 

[Alex41]

Ahhhhhhh....I get it now. Well at least I've fixed the pinion angle. Haha. Looks like I'm getting the anti hop bars and some different uppers soon.


On another note, do F body lowers fit? Thanks guys. Alex.

 

[greer_racing]

i don't. the arm looks easily 2 inches higher at the back from were it was, even moved his pinion. how did it not change? i can see it rotating under load though

 

[LS6 Tommy]

i don't. the arm looks easily 2 inches higher at the back from were it was, even moved his pinion. how did it not change? i can see it rotating under load though

It doesn't have anything to do with the angle of the arms. It's about the mounting points. Adding the tabs like he did in the picture raised the arms, not the mounting points. No matter how high the pumpkin end of the arms get moved, if the bolts are still in the stock locations, there will be no change in IC.

Tommy

 

[greer_racing]

ok, so that tabs not solid on his rear end. it still has the bushing in it?. i know what you mean now because my lower brackets have the holes drilled on an angle from each other. if those tabs were solid on the rear end and the bushing in the control arm, that should work because the short arm is the reason its angled down. the car must not be very low if you can fit that or no hop bars

 

[grizwald]

I'm not sure I'm understanding your interpretation, because the bushing doesn't have anything to do with it. pretend for a second that he has a stock, un-modified control arm on the rearend. it would be mounted in the stock location, right to the ear on the housing. now, imagine that the ear on the housing was raised by 2", and the mounting hole for the control arm is now 2" higher. the stock control arm bolts to that now, moving the pivot point of the control arm 2" higher, and as a result, changes the control arm angle, and instant center. that's the idea with relocation brackets. they raise the mounting point for the upper control arm on the housing. for the record, I'm using 2" as an example. I'm not sure what the exact ideal height should be.

 

[Alex41]

The way I understood it (kinda felt stupid I didn't think of it before) is to imagine the two bolts on the arm as a line. No matter where the arm is, the line the two bolts make and continue forward make the imaginary line to intersect with the lower control arm imaginary line, thus measuring the instant center.

Long winded I know but I hope that clears it up. Now I just need to ACTUALLY fix this problem. haha

 

[LS6 Tommy]

You understand it perfectly. Here's a really clear diagram from Baseline Suspension. It's obviously not setup the same as a stock G-body, but it shows the basic concept:

http://www.baselinesuspensions.com/info/4_LINK.pdf

Tommy

 

[greer_racing]

looks like its time to spend some money, i have bmr lower brakets on mine and wouldnt recomend them for a lowered street car but they do work

 

[Alex41]

Small update....

Today I bought some 3/16" plate from Lowes and made myself some lower control arm relocation brackets, this time ACTUALLY changing the instant center. I don't know what else to say but time wasted.....

I'm starting to think the F body springs and old 255 45 17 tires are the culprit here. I am planning on buying some new wheels and tires soon. 275 60 15 BFG street tires should be better than those 2004 low profile things. Thoughts? Thanks. Alex.