I know the advantages of running the control arms in the lower holes in the relocation brackets, but are there any disadvantages to it?

 

From what I understand, if you get it too low, it can cause problems under braking. Upsets the suspension

 

More likely to get brake hop.

During hard cornering, the rear axle may want to run a little wide. You'll probably have to be a little more careful about adding lots of throttle as you exit corners.

The above situations are more noticeable when the car is left at or close to OE ride height than when lowered.


Norm

 

It'll hop like crazy when you're backing up too...

You can overdo it, and have the rear end jump, and remove weight off the tires after a few feet down the line. Set the LCARB bolt holes for your best 60' time.

 

With they're to low you can induce roll steer. - As one side compresses the arm gets closer to level, while the other side extends, thus getting even further away. So the compressed side is pushed back, while the extended side is pulled forward, thus turning the rear end under the car.

Also, as Sonic noted, excessive angle will cause too much initial "hit" thus causing the tires to unload. Tighter shock valving would negate much of this, but would also hurt the supensions' reactions down track and make the car considerably more stiff.