rwhite65,
I have 17x8 TT2's (4 3/4 backspace) on my 66. I am lowered about 1 1/2", running 4 wheel disc, Trans Am Racing power dual master. I run 235/45 front and 245/45 rear. Before I switched to 17's I was having a problem of "squating" the body onto the tires when I would nail the throttle. I added subframe connectors and traction bars before going to 17's and have had no problem with any contact at all.
I will give you the advice I was given for the rims: HAVE THEM CLEAR POWDER COATED. Unless you want to polish them every other day. I just wash mine like the car and they are good as new.
You can see pics of my car at my site:
2MFF Fab Shop
Brake booster info is at(make sure Java is on):
Trans Am Racing
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347 (Coast High short block), 279/284, TFS TW heads, Stealth, 750 Holley, Flowtech hdrs, Dr. Gas X, 2 Chmbr Flowmaster, MSD 6AL-Dist.& SS coil, March serpentine pulley system, Art Carr C-4 (Soon to be a Richmond 6 spd), Currie 9" w/3.50, alum Drv Shft, susp mods, Total Control subframes & tower braces, Trans Am Racing power dual master, 4 wheel disc, 17x8 Torqthrust II's
Something up my sleeve
In a 66 coupe