Are you even reading what's been posted? Adding 80 HP is not 'easy' with the Challenger, and you're tossing your powertrain warranty in the trash when you try. The PCM cannot be tuned without actually hardware modifying the PCM itself, or buying another one. That puts you in the $1K mark,
just to be able to tune. Doesn't touch the cost of the other parts
or the tune itself. Also, have fun finding a shop to tune the Mopar stuff, they're few and far between just because of these issues.
As far as the torque deficit in the mustang, unless you're adding forced induction ($5K+ and bye-bye warranty) or turning the motor into a stroker (see previous parenthesis), there is no replacement for displacement.
Adding power without major mods is not 'easy' anymore. The motors coming out these days are pretty damn optimized by the factory, out of the box.
Again, LOLWHUT?
Comparison on chevy.com.
Go ahead, look it up. We'll wait.
That's $19k. Here's a simple numeric line diagram:
$37k ---------------$56k
Numbers to the right are higher than the numbers to the left.
In all seriousness, they're not in the same ballpark. The vehicles are in two different categories, as far as utility and performance go.
The problem is, dealers don't order base cars. They add every damn option under the sun in the highest trim models for the lot, because they've got the 'wow' factor and the highest profit margins. Easy fix, requires a bit of patience? Order what you want.