Putting larger engines into Plymouth Valiant-based cars
Greg Purcell wrote that putting the 440 into a Valiant is fairly easy:
The "elephant ears" are easy, but they are quite outdated..the "state of the art" piece right now is a mount made by Schumaker Creative services. They have a system to bolt the big block to either a 6 or an 8 cylinder k-frame depending what your duster had in it.(and what year it is). Their number is:
Schumacher Creative Services
2025 N.E. 123rd
Seattle, WA 98125
As far as the front suspension, it depends on what you're doing with the car...If it's a race only car, Mopar Performance recommends the 6 cylinder torsion bars..this gives the same effect as 90/10 shocks, causing the front end to "lift" upon acceleration...but handling is nonexistent!
The Heavy Duty bars are available in ratios up to road race capability, but 340/360 bars have always worked well for me.
The trans mounts in the same position as the small block or 6 cylinder.
You need an 8 3/4 rear with gears matched to your cam..(again it depends on what you want the car to do)
Exhaust manifolds or headers are the hardest part of the swap...there are fenderwell headers (easy to install but reduce turning radius) or "underchassis" headers which are a bear to get in! I use a stock "log" manifold on the driver's side and mill it to half thickness (to clear the steering column) I use a B-body HP manifold on the right. (Schumaker also sells manifolds guaranteed to fit).