[DeTomaso] adjusting rear camber with a bay brace

[JDeRyke at aol.com]

FWIW, the Pantera's rear body structure is flexible and needs some sort of 
rigid brace joining the upper ends of the rear coil-overs. GT-40 race team 
guy Carroll Smith once described the Pantera's rear suspansion as 'being 
connected to nothing at all' in racing terms. And this was with narrow, 
iron-hard OEM tires.... There is a gradual sag of the spot-welded rear structures 
over time that results in excess negative camber as the parts all shift a 
little under load. An adjustable bay-brace fixes this-first by being more rigid 
than stock, and second, by allowing progressive adjustments to push the 
structures back to near-stock settings.

Note- you CAN pre-load the rear structures to move them back- you just 
can't do it all at once, or buckling of some body panels will likely result. But 
small loadings over a period of weeks will restore the rear wheel 
alignments without the band-aid of extended upper a-arms, or cutting & welding the 
rear frame longerons as some vendors can do. I did enough adjustment as an 
experiment two decades ago on our '72 with a Hall bay-brace to restore stock 
rear alignment, and have successfully done this to others. But it absolutely 
requires patience AND the type of steel aftermarket brace that spans all the 
way from the  insides of the welded pockets. 
Trying to use only the flimsy flexible slotted attach-tabs or a stock 
bay-brace (or an aftermarket one that has short ends) just will not work. Note 
also that home-built bay braces with racy rod ends suffers the very same 
problems of depending entirely on those flexy slotted tabs. Not worth the bother 
IMHO. If you have one of the mostly-decorative aluminum bay-braces, it can 
be converted to actually work in the manner decribed by adding aluminum 
extensions to the ends so the length is correct. TIG-welding is ideal but it 
might be possible to bolt on extensions- I haven't tried. Nor have I tried 
welding doublers to the tabs or filling up the slots to strengthen them- the Hall 
brace fixes things adequately for me.

The way that worked for me is to jack up the car with a steel Hall brace 
disconnected on one side, then install the brace and crank about 1/4- 1/2 turn 
of pre-load in before lowering the car. After a week or two of driving with 
the brace set this way, jack it up again and crank no more than another 
half-turn of pre-load in. Repeat as necessary, until over time, the rear camber 
is again correct. Trying to hurry the process will cause major body 
problems, so be patient; it may be your car needs less pre-load or correction than 
ours did. The mentioned 1/2 turn should be the MAXIMUM pre-load done at one 
time. All Panteras have SOME rear structure collapse so there's no single 
adjustment procedure that can be done safely & effectively to all. But with 
the cost and rarity of suitable rear tires that fit out cars, this will at 
least extend rear tire life even if you don't drive hard enough to gain any 
handling benefits from correct rear wheel alignment; the inside tire edges will 
wear rapidly with too much rear camber. 

Bottom LIne- this CAN be done, at home, but you must be patient! You're 
trying to undo 40 years of progressive sag, and as with human bodies, fixing 
sags does not happen instantly with a "reset" button! Good luck- J Deryke