Torque boxes have got to help and subframe connectors should be a bigger improvement. You guys that installed them, did you see a big difference and describe the difference if you would. Thanks
On both of my cars I installed the torque boxes and the subframe connectors at the same time, so, I can't really say how much they help individually. On my Duster I also installed J-bars and a tubular radiator support brace while I was adding all the chassis stiffening. It makes a big difference over stock, especially with improved suspension and tires. Without the stiffening there's a lot of creaks and rattles, and when you start pushing the car harder in the corners I could feel some vagueness in the response that was eliminated after the chassis stiffening. With my Duster is wasn't as significant as my Challenger, but the challenger has rust issues in structural places. That car would actually give me a "spooky" feeling when I was out in the mountains having fun, the chassis flex was that evident. But again on the Duster it was never that obvious, but it doesn't have any rust issues.
I haven't had the Dart back on the road since I did the subframes and torque boxes on it. I did pretty much the whole USCT stiffening kit on that car as well, so it also got the inner fender braces and radiator support brace. I know it'll make a difference, but on that one I don't have much of a reference because the only times I had it on the road it had the stock suspension and skinny little radials on 14" rims.
