Honestly...how good was the 318...mpg / durability / hp

I still have a couple teens, one in a 75 power wagon, it still runs smooth, no smoke or tick, shame I am going to use it for a parts truck.

I have another one sitting under the work bench, I went thru it, nothing fancy, it was siezed when I got it. PO had yard driven it around, with the soft plugs rotted out in the heads.
I had a heck of a time getting it apart, the wrist pins had semi seized from over-heating of the engine.
A member here gave me a stock set of rods and pistons out of another engine.
I had the machine shop dip the block, turn the crank, new cam bearings etc. Put it together with a fresh set of 2.02 J heads, and a summit 6900 cam.
I think that I am going to stick it in my 70 challenger, with a 671 on top, and see how long it will stay together.
I have all the parts, just need to buy a new clutch kit.