Well getting a used motor with the idea of building it up as you get spare funds and have it ready for action when needed while you continue to drive what you got ain't a bad idea. What you'd want would be a rebuildable core motor. Usually sold cheaper as a core than something sold as ready to go, ready to run etc.
Unless the truck is "down" and I need it back up and running again right away, that's how I usually do things. But if it runs fine as is, no oil pressure issues, etc it's a known quantity right now. Any motor you're gonna find no matter what a seller may say is an unknown. I've gone thru all the work of an engine swap not knowing that my "good runner" replacement was really a turd, and it doesn't make me happy. Even if you put the super 6 setup on this engine for now while you build up the replacement, that's not a bad thing. I'd hate for you to replace a known good engine and wind up with a turd. Lots of wasted effort.
At least you don't have to be in a hurry to find another engine if yours currently runs. Means you don't necessarily have to take the 1st thing that comes along, less chance of getting burnt. If a super 6 stack comes along in the meantime before you get your replacement engine at least by putting it to use on the current engine there's less chance of the carb going stale and getting gummed up from gas having sat in it while you build the engine.
That's what I'm doing right now. I have a replacement engine in the works, but my truck runs and drives as is. And others may say to backtrack to the lighter duty 904 if your 727 is working as it should, I'd leave it alone. I was surprised but glad too, that my truck has that trans vs the lighter one.
The only problem with building an engine in your spare time that you don't need right away, is when you have a goal or plan for how you want to build your engine to suit your needs, is going on forums like this and seeing what everyone else is doing and the " what if" thing gets in your head and the "pressure" to change what you started off doing, because that's what these guys are doing with theirs, you start 2nd guessing yourself and your build plan.
Don't get me wrong, we all need some guidance with such a project but as my goal is low rpm more grunt /because I'm building a motor for a truck that will be used like one, while someone else may be building a high rpm screamer, you get to thinking that you oughtta build yours like this guy's motor.... Or the "might as well's" kick in.
