Welcome to the forum first off.Ultraz said:Here's the deal, I have a 1986 Astro Automatic and it has the 4.3 L. It's not going to run much longer. Here's my opions......
A. Rebuilt the 4.3 L motor
B. Put a used one in
C. Put a 350 V8 that I have just sitting in the garage that has a fresh rebuilt?
What other year 4.3's would work without the wire harness hassle?
I would like to get pretty good gas mileage since I travel a lot.
Let me know your thoughts, Thanks
Might I suggest you haven't told us what is wrong with the current 4.3,so it make it hard to suggest to rebuild it.The 1986 is a TBI if I am not mistaken,so that does give you a wide range of choices for used ones.You might want to take a look at this link to see pricing and availability at junk yards.
Now that brings us to the 350.Question is did you have other plans for it???.Seems you built it for a reason that didn't include a install in the Astro.What is the overall condition of the Astro comes into play as well.In terms of gas mileage with the 350,many report the same as the 4.3 or better primary because the engine doesn't work very hard to move the Astro.
Hope this helps and let us know what you have decided.