Rear bars on gm 4 link

[Hammadown]

Can someone explain what moving the top bars down on the chassis would do? Or why someone would do it? On a car I bought the original owner lowered the front of the bars down roughly 4 inches and the mounts on the rear end are forward of center and about a inch above the housing.. car works pretty good just curious why some one would do it,

[billetbirdcage]

Can someone explain what moving the top bars down on the chassis would do? Or why someone would do it? On a car I bought the original owner lowered the front of the bars down roughly 4 inches and the mounts on the rear end are forward of center and about a inch above the housing.. car works pretty good just curious why some one would do it,

Typically in factory position the upper bars run slightly uphill to the frame ride height. Doing what they did added downhill angle to the frame in the upper bars, so when the rear end pinions up (on throttle) it lifts up on the chassis instead of pulling down on chassis.

[JustAddDirt]

I would think that would effect roll centers as well.
I believe it would move roll centers higher I believe

The roll center for a GM metric chassis is found by drawing a line between the theoretical intersection of the upper links and the theoretical intersection of the lower links . The roll center is located where the line crosses the vertical center line of the axle.

[Manymore]

I watch the street stock guys at the UMP tracks and nothing there doing in theBack of the car makes sence to me. They drop the left lower to the ground and Run a hike up shock, with the upper arm angles the roll center seams to highBut the top runners are all doing it. Seams like there mocking a modified setupBut how could they get any forward bite or are they getting just enough rear Steer to make a diff?