Yeah, I was pretty amazed when I saw the leak down results. Remember, this is not the original engine from the factory. It is a parts store engine installed in 1988 at a repair shop in Portland OR. That's all I know about it. I can't attest to the quality of the rebuild job prior to putting it in my car in 1988. Kinda wish I had the original numbers matching motor. Anyhow, it's remarkable that the engine runs at all, but that's a testament to the durability of the slant six. My concern with the spare engine that I have in my garage is this: If I put the money into the engine swap (not going to do it myself because I don't have the tools and facility to do it with), what's to prevent something else happening to the replacement engine in 10K miles? Now, I just went and threw good money after bad.