. . . 94 ram 250 w/ 318 . Getting ready to rebuild the motor a& trans and I am trying to find some good suggestions over the next couple of months
1st question is what's your budget? 2nd one is what do you want to accomplish?
There are LOTS of things you can do to a 318 to really "wake it up" for more power & better fuel mileage both, but the best options are expensive. Same goes for the transmission (assuming automatic), but getting an aftermarket valve body and/or shift kit isn't really all that expensive -- if you want to change the torque converter, that's a different matter.
And I always say "think system" rather than individual parts -- the best parts $$$ can buy won't do you any good if they're not designed to work together. For example, you can put 360 heads on a 318, but since the combustion chambers are larger your compression ratio will go down, so you'd need new pistons to bring it back up.
Edelbrock makes a really neat EFI system for a 318 with 360 heads which will give you a lot more power & better fuel mileage too, but it definitely ain't cheap! But if you can get away with it (inspections, emissions), a good aftermarket intake manifold & a Carter AFB 4-barrel carb will work great too & not "break the bank". Headers & a good dual exhaust system isn't all that expensive either -- unless you have to use catalytic converters (for inspections).
So you have LOTS of options & really the only limiting factors are 1) what you're willing to spend & 2) which combination of parts will work together to accomplish your goal.
"One of the problems with 'majority rule' is the majority is usually wrong." -- Thomas Jefferson