Seeing as parts are becoming less available for our cars. Dont really want to spend 15k for a built motor. What is a good price for a used one? Found one with 70k miles for 4500. Thinking of having a spare just in case.
This depends on a few things. Do you know for sure it has good compression? 4 thread or 9 thread heads? Are the heads loaded with cams, valves, followers, etc? How do the cylinder walls look? If it's a healthy setup with 9 thread heads I would say that's a pretty good deal. Even with 4 thread heads it's a good deal. It's kind of a gamble if your buying for a spare. It may come with a 30 day warranty but that won't really make a difference if it will just sit for a while. I have seen so many guys get burned buying assembled engines and when they get them in and running they have issues. Definitely make sure you trust the seller.
If it's going to be a spare why not go through it while it sits? You don't need to go crazy on it. Throw in new rings, bearings, and gaskets and you know you have a good engine ready to go.
You can do a spare engine build on a budget. Acquire all the parts yourself and bring to a local machine shop. Aluminum block $300, Cobra crank $400, used rods $400, Aviator DB/DC heads $300. In no way do you need to spend $15k