Differences in 1 3/4" round vs 2" square tube chassis

I had heard from a few people that mastersbilt has been making chassis just for crate racing in mind. I was just wondering if there was any truth to that. I just bought a 2006 smackdown 2" square tube chassis that I plan on running in crates this yr. Several guys running supers locally are having great success with these square tube chassis and I really like the idea of square tube for the main frame rails, but I also know that they would have to weigh quite a bit more than say a 1 3/4 round tube chassis. So I guess what I'm trying to ask is anyone running the 1 3/4 chassis? I've done as much research as I can about the differences in the two. People say they usually preferred 2" square over round because they tended to last longer and was more rigid. (I posted this in the crate section also, but I figured you guys running supers would have more info about the subject)

We ran both styles, I'll take a 2x2 heavy rail car over a 1.75 round mastersbilt any day. The 2x2 car was more responsive to adjustments, and had more sidebite and drive than the 1.75 round car IMO.

Thanks for the quick response and info I really appreciate it. Just out of curiosity, I wonder how much the 2"round and 2"square are alike as far as stiffness and and responsiveness to adjustments. I know the square is going to still be the better choice, but the 2" round has gotta be better than the 1 3/4" right? Also another question, I've been told that some of the square tube cars were made from thinner wall tubing than others. For instance I've helped raise the ride side frame rail in 2 smackdowns and they both had 2x2 .120 tubing. But like I said I've heard some were made with thinner wall.

The square is the way to go. My 2012 main rails are .083.

Hey guys I really appreciate the insight, y'all have saved me a lot of headache. If anyone would like to comment on the subject I'd really like to hear your info/opinion as well. I'm really excited to see how this car is gonna run, before this car all I've had is Rayburn's on 4 bar.

Seen both win.

I was told the Mars MasterSbilts had the thicker frame rails. I have not seen for myself though.

There are a lot of more important things to worry about when getting a chassis than what shape the rails are. What thickness tubing is the halo and supports made of? How does the car survive hard hits of all kinds? Is there extra bracing? Is it chromoly or not? What kind of support does the builder offer? Do you understand how to adjust that make of car? What frt end design is it? I have had both round tube and square tube cars. I feel square tube cars last slightly longer but would look at all the other factors first. JMHO.