No
An RV cam is an aftermarket part.
Many RVs have them added but it was not standard from the factory.
yes
Yes.
yes but it has to be 83 or newer
No. The 400 is externally balanced and requires it's own flywheel.
No. Standard 350 engines have 4.00" pistons, standard 400 pistons are 4.125".
It should work well.
.030
its about 350
It depends on the cam.
The main journals need to be turned down.
It'll fit, but those big combustion chambers will probably reduce the compression ratio to an unacceptable level.
377