I have 1" lowering ball joints on my 88. I am interested in upgrading the front brakes but most of the descriptions for the brake kits say the lower arm will interfere because of the balljoints. Is there and kit that will fit?

Me too!

The one with the best "chance" is the 13" Viper rotor kit from WCF. I say "chance" because I haven't ever tested them...

The 12" C4 ones are 2.19" deep and can rub the nose of the lower a-arm with the stock ball joints (depending on how low you go).
The Viper rotors are 1.71" deep, so they "should" have enough room to work with the lowering ball joints again possibly depending on how low you go.
http://www.westcoastfiero.com/brakes/13/index.php

[This message has been edited by 1MohrFiero (edited 05-07-2015).]

Are these a problem with Grand AM/Beretta brakes?

quote Originally posted by 1MohrFiero: Are these a problem with Grand AM/Beretta brakes?

First, its only an issue on the 88's because their front lower a-arm is closer to the backside of the rotor.
Second, its only an issue if the upgraded rotors are deeper than the stock 88 rotors, because that is what moves the rotor closer to the front lower a-arm.

The grand am rotors are the same depth as the 88's, but they wont fit over the flange on the 88 front wheel bearings unless you turn them down. Several in years past have modified their bearings to allow the use of the grand am rotors vs. the stock 88 Fiero rotors because they were cheaper.