I need a rear sway bar, any ideas on stock 7/8 or 1 inch. I have 1 1/4 in the front with after market boxed rear upper and lower control arms. Thanks

There is ration of fronto rear sway size. Maybe some where on PST or some suspension site.

I would guess the 7/8's would be fine, that's what came with the F41 suspension isn't it?

I think you are right about 7/8 being stock and I also heard that there was some ratio with the front and back but cannot seem to find it. Just have to keep looking, its out there somewhere.

I have 1 1/4 Trans Am front and 1" Hellwig rear sway bars on a 68 chevelle and it handles very well.

"Hellwig", not familiar with them? Are they any different from any other aftermarket sway bar? How about price?
Thanks

I think you can buy Hellwig Sway bars from summit. They are made from heat treated 4140 alloy steel which is a lot stronger than the cold bent bars.

Rod,
Use the stock one. I'm sure there is some magic formula, but the main thing is keep the rear bar smaller than the front. Save yourself some bucks. Unless you plan on some serious road racing, you will not be able to tell the difference.
John

I ran a stock 7/8" bar but prefer the 1" with my combination - stock rubber bushings, boxed factory control arms, moog 5380 front, 5409 rear springs. This combination is more balanced than the 1 1/4 fr 7/8 rr combination I had before. It all depends on your setup what performs best. Aftermarket rear control arms/bushings will probably flex less so you will need less bar. Hope this helps.

I'M RUNNING 11/4 FT. W/ 1 REAR,POLY BUSHINGS FT & REAR,SSM LOWER REAR BARS, CUSTOM REAR SPRINGS W/ BAGS, IROC STERRING BOX AND PUMP REGULATOR, CAR
DRIVES LIKE NO OTHER 70'S CAR I'VE EVER DRIVEN !!
ROB....

Everyone should read all the info on the Global West "A" body pages.
http://www.globalwest.net/1964-72%20A-BODIES.htm

Interesting, especially where they have you using no rear sway bar at all!
http://www.globalwest.net/1964-72%20A-BODIES.htm

I admit to having trouble with that idea especially since I've done my mods in steps.
I guess for their plan to work it should all be done at once.
BTW: Any ratio formula GM might have used for sway bar sizes was probably to ensure it still understeered when they were done. (IMHO)
In my case I used a 1" Addco rear sway bar with the stock (13/16"?)front bar mounted in poly bushings.
This was on a 6 cyl 64 Malibu 2 dr.
I think a lot of times there is not enough thought given to whether the car is a 6 cyl, sb, or bb; 2 dr or wagon; early or later model.
(Check the factory curb weights)
Suppliers and car owners seem equally guilty of this.