Sir Harmony

Lowered
I don't get why people say the car must have an aftermarket PHB when lowered. I've been lowered 1.5 for about 4yrs, and on 315/30/18 with spacers for nearly 2years. My rear has looked fine (albeit the gap over the tire on one side being slightly higher than the other side). I rolled my fenders last year, and haven't had any issues with the 315's or suspension in the rear. As for the front, the 275's end up balding on the inside. I thought it was from aggressive cornering, but after the second set or tires, I now know its from not getting an alignment. The car ran straight as an arrow, which was why I never bothered.

LCAs
I have an adjustable phb, adjustable LCAs, and LCA relocation brackets. I get the adjustments for the PHB in order to center the axle, but what can I accomplish with the LCA's? I adjusted them toward the rear if the vehicle, and I'll admit it looks 'different'. I haven't driven the car yet, pending other upgrades, so I don't know what to expect. How would this affect driving, as opposed to either centering the wheel in the wheel well, or positioning them toward the front in the wheel well?

PHB
One small note. I adjusted the PHB all the way in with the passenger wheel down, and noticed that the wheel was rubbing on the inside. So the next day, i adjusted the same wheel out with both wheels suspended. The driver side seems to always be .5" further out than the pass side. I dropped the driver wheel and adjusted the PHB so that the pass side appeared to be even. As soon as I dropped the pass side with everything on the ground, it shifted, resulting in the driver side being the initial .5" further out. What am I doing wrong?

JD_AMG

The people saying its a "must" are likely the ones selling the parts.
No, its not something you "need", but it does center the rear end and in many cases prevents tire/wheel inner fender rubbing.
As for the front, you lowered the car which changed the geometry, it doesnt matter how strait it drives because you likely have too much negative camber which can wear the inside of the tires (too much toe will do this too).
Adj rear LCA's are generally used for fitting big slicks/radials in the back. Usually pushing the axle back some so the tires don't rub the inner fenders (the front of the inner fenders are closer to the tires then the rear, the rear has more space).
Doubt you will notice a difference in driving.
When adjusting the PHB you need the rear to be sitting level on the ground, not hanging. You adjust it to center the rear at ride height, then drive it and make sure nothing is rubbing. If one side is rubbing you can adjust it away from that side (or do more BFH mod to that side).
With a PHB setup the rear doesn't move strait up and down, it moves in an arc like this:

So as the axle moves up it also shifts to the right, and when going down it shifts to the left. This is where tire rubbing issues can come in and why companies make adjustable PHBs (and also watts links to get rid of the arc movement).

therabidweasel

iTrader: (5)

Adjustable lcas can also get you deadnuts on the axle thrust angle.

Sir Harmony

JD AMG, I couldn't have anticipated a more thorough response. Many thanks.

I was going to create another thread on adjusting the front, but perhaps I can ask it here.
I went to an alignment place, and explained the inner balding issue on the front. The guy behind the counter (has a Belair) seemed to know about the suspension design and explained that it can be adjusted slightly to correct the issue (he made a reference to either the mount or LCA if I recall). Can someone explain to me how the camber can be adjusted, because I've looked at the mount and entire shock setup and don't see how it can be done. I know suspension shops have their ways, but since i made the assumption that it was only the camber that was off, i was looking for just a way to adjust the camber. Is it possible that the whole front (toe, etc) is off? I considered purchasing adjustable lower control arms, but that would mean going even lower (1" or so) than the ultra low 1.5" I currently am. That would made driving more of a task than a thrill.

JD_AMG

You shouldn't need anything aftermarket to align the front suspension. Have the shop put it on a rack for you and align it to the specs you want.
Scroll down this page to see some specs:
http://www.angelfire.com/my/fastcar/suspension.html

Ive seen a DIY thread for front alignment but looks like too much of a PINA without the machine IMO.
edit: found the thread:
https://ls1tech.com/forums/suspensio...alignment.html

brigade24

checking and adjusting camber is not difficult...its checking toe that poses challenges.

changing your camber will require you to change your toe because both points of adjustments are at the bottom. There is a camber bolt connecting the LCA to the k-member which needs to be loosened to make adjustments (the camber nut faces the rear of the car). the caster bolt (caster nut faces the ground) also needs to be loosened so the LCA can be adjusted out meaning you are adding negative camber. Adjusting in the LCA (pulling in the LCA towards the k-member) will add positive camber. So if positive camber is added without adjusting toe, you will have (in short order) inside tire wear because it creates a "dragging" condition (left tire wants to go left; right tire wants to go right...looking from the top of the car think of your front tires forming a "V"). The car will track straight if you have perfect toe out (toe out equal on both sides)...

so yes the inside tires will occur wear if you have too much camber but they will wear out exponentially faster if you have toe out condition.

youtube is littered with "how to check alignment" videos but i haven't found any for our f-bodies.

Sir Harmony

Thanks for the great info guys. I'll take it to the shop to have it aligned as soon as I finish the summer project; Just a few things left - reprogram ecu, and do something about my nitrous delivery.