I know the topic is about the size of a front sway bar, just responding about the difference and I don't have the answers.
A friend of mine used to own a '64 Vette with the 365hp 327. He purchased a rear sway bar from one of the aftermarket manufacturers and one Saturday we got together to install it. It was not possible with the drum brakes. I got online to read about this problem and found some interesting info on the topic. Only the Vettes with the big block used a front and rear sway bar due to the extra engine weight. From the factory, the front bar for the big block is larger in diameter than the small block. A rear sway bar for the small block Vette was not a factory option even at the parts counter. Vettes were way better engineered to take turns with the independent rear suspension/shorter wheelbase/less weight and adding a rear bar to the small block upset the handling and would cause the car to spin out in a turn.
I realize a shoebox is not a Vette. Just trying to point out that the size of the bar does make a difference.
Last edited by shoeboxpaul; 11-15-2019 at 10:17 AM..
My 2 cents, we chose the smaller sway bar. It makes a big difference, but it also makes for a stiffer ride overall. For our purpose with 15" wheels and a raked stance along with a bench seat, handling isn't a priority. For me, the smaller sway bar was perfect. It made a huge impact in handling for basic corners. It was a good compliment to our mintubbed rear with 4link and still a nice ride quality. I didn't do the rear sway bar because the way it is now it handles better than the smaller front tire and the ole bench seat can handle. Sway is no longer a limitation.
To each their own. I have friends with very good handling (AM chassis) trifives, but it just wasn't for me. I wanted an old fashion hot rod that was comfortable and safe on the street. I've got other cars that are more appropriate for carving it up. Either way, you will be happy.