I've purchased four crate engines form a "dealer in Mass" this year, 3 big blocks were dated 2011. There isn't a ton of stock on the 502 marine crates right now so they probably had to find one somewhere else. I can understand how you'd feel at first glance finding it's an '06 but as others have stated it's really not a big deal. The only downside for some is that it probably doesn't have a mechanical fuel pump boss like the new ones do. Other then that the materials and technology have not changed so there is no difference in value to a new one. The Merc package you referenced that is a few years old has older technology, programming, calibration, external parts, etc.

For all the valve spring guys.. Do you know how much the valve spring on a 502 is compressed with that tiny cam and a lifter that has its plunger fully depressed?..
Bob Teague also says that synthetic oil is too slippery..
I have witnessed and tested with my Rimac the same results as cubicinches. Although not for as many years and as many engines.. :ernaehrung004:

That Bob teague thing about oil being too slippery for roller cams came to mind when I was reading this too, I do agree that a valve spring can lose some seat pressure from sitting in the open position for too long but knowing how low the valve lift on a 502 crate engine is too I would not worry about it. I used to crank my motor over once a month in the winter but I quit doing it because I think its harder on my motor to keep cranking it in the cold (wash down) than just leaving it alone, yeah I could disable the fuel pump but it hasn't made any difference with my .610 lift cam I am running. Now, if I had a 1400 hp all out race engine with a .800 plus roller cam, I WOULD be backing the rockers off it was going to sit too long, Smitty

What causes a valve spring to weaken is fatigue from reapeated cycling over and over again from heat and compressing, not sitting in one position.

Building a street engine for a GTO does not make a person an expert in metallurgy.

Put the engine in and run it

:cuqui:If you could comprehend (that means understand) my previous posts...I said that there were other factors involved in spring fatigue. My whole point to this was that if he did find a "new" motor from '06...that I would be suspicious, and look very closely at all the internals on a motor thats been sitting in a warehouse for 5 years.

And no where did I state I was a metallurgist...lol. I happen to be a skilled trades tool & die welder at GM...so I have a LITTLE experience with tool steels. Thanks for your input tho. :op: