Here are some numbers from factory literature
Challenger wheelbase 110 inches Cuda 108 inches
Challenger overall length 191.3 inches Cuda 188.4 inches
Challenger front track 59.7 inches Cuda 59.7 inches
Challenger rear track 60.7 inches Cuda 60.7 inches
Challenger curb weight(dry)(small blockV-8) 3390lbs Cuda 3370lbs
2 inches shorter wheelbase, less than 3 inches shorter overall length and 20lbs lighter for the Cuda
The floor pans are the same on these cars too, so the seat placement is the same.
If you ever driven a car that had low original miles, even versus a car that was fully restored, you'd see that the low mile original cars are so much tighter. Thats my personal experience.
Again, it's more of what is different between the cars you compare option and condition and equipment wise, then what the cars are different from the factory in an exactly same optioned car. even the alignment settings and torsion bar ride height can make a big difference in how these cars ride and handle.
I've owned over 40 of these cars, big block, hemis, small blocks, 4 speeds, 5 speeds keislers, autos, dana rear cars, you name it.
Carl is right on in that the small block cars handle much better than the big block cars in stock condition. My AAR was the best handling E-body I have owned, hands down. poly bushings but other then that and radials, a basicly stock car.