I have a 1973 Roadrunner with a siezed 340 and 4 spd. I bought it very cheap due to the stuck engine and rust issues. I also bought a 1976 motor home with a 440 and automatic transmission. It was also very cheap as there is no reverse in the transmission. (I'm planning on using the motor home as a chicken coop)
Now the question, how difficult will putting the 440 into the roadrunner be? I read the thread below with the other motor home however it had an automatic transmission. I know I will need to replace the bell housing and get motor mounts.
Or would it be easier to find a 360 and put it in?

 

the 360 will be alot easier it will drop right in the 440 will be more work you will need a bigger radiator big block motor mounts a beefier rearend and probably a few things i am forgetting about but hey its your car your build do it how you want thats the fun of restoring mopars good luck which ever way you go

 

It would be cheaper and less headache to rebuild the 340 motor. THEY ROCK!!!
But if you decide to put a 360 in it, make sure it's an LA 360. (pre 1992 engine)
After 92 they are magnums and since that is what I have, they are a pain in the a$$ to convert to 70's style cars.
273 to 360 engines will bolt right up to that A-833 4 speed tranny. And parts are really common to find.

If you put in a 440, you have to change engine mounts, tranny bell housing, driveline, carb/shifter linkage, exhaust manifolds/headers/collectors.......I'm sure I missed something else.
That motor home tranny won't work in that car.

Chicken coop??? What kind of chicks do you hang out with?

Good luck with your Mopar project car.
Let us know what you decided and post some pictures....

Mopar_71

 

while it is your car i do agree with mopar 71 about rebuilding the 340 they are good engines i have a 340 4 speed set up in my dart and i love it granted it might not get you down the road at the speed of light but if built right you will not be disappointed you can get very good hp out of a 340