supertech 85mm pistons?

[mprhead5]

I think that core shift would be a concern.  you might end up with a thin side.  btw, burying the block is just ridiculous!

who the hell know why the guy did it. He built some pretty competitive motors for world of outlaws and was a chief engineer at MSD ignition.

I found this explination
when a piece of iron rusts it actually pulls the molecules tighter together therefore creating a denser thus stronger iron.

John Deere dose this with their big tractor blocks to "season them" out in the air anyway not buried.

another source said

Used to be an old engine builder's trick to take a stripped engine block and bury it in the ground for a year. Then to dig it up and perform a complete rebuild on the engine. Theory being 2 fold. All the stresses would be relieved from the engine block and the molecules would "line up" with the earth's poles making for a stronger bond

[CharlesE]

mprhead5:

I'd be interested in seeing the source for your quote about rusty iron pulling the molecules tighter.

The structures that I design, are as well protected from corrosion (rust) as the client can afford.  We use epoxy paints, galvanizing, stainless steel, and electrical systems to prevent corrosion, simply because the rusting process changes the steel into larger iron oxide molecules which flake off the base material easily.  One of the biggest concerns with steel reinforced concrete is that the steel corrodes, creating a layer of iron oxide, which is larger than the steel molecules it replaces.  That larger size presses outward from the rebar, eventually cracking the surrounding concrete.

I'm not a large person, but  I've driven a carpenters hammer through a 1/2"  thick steel bridge plate that was heavily corroded.  Even weathering steel, which was supposed to limit the corrosion to a tightly adhered iron oxide layer, has been found to not protect, let alone strengthen steel in practice. 

I know of no engineering practice that recommends letting unprotected steel get damp, and usually quickly rusty (Arizona may be an exception to getting rusty!). 

[mprhead5]

Well blocks are iron not steel. Ill get some sources and post up some links. I searched for seasoning engine blocks and came up with a story about john deere letting cast blocks weather outside saying that oxidation strengthened the iron. The other source was a referance to burying the block as a practice done by old school engine builders like the MSD guy i met. Ill post some links and you can decide for yourself.

['95MSM]

Of course I can't speak for the metalurgy of the Belfab rods, but the finish work is gorgeous.  At arms length the parting line for the cap begins to get hard to find.

[mprhead5]

Found this inreresting thread in a machinist forum that talks alot about seasoning iron castings. Seem letting castings sit outside to season for a year was a common practace in the first half of the 20th century which it probably why it was an old engine builders "trick". Due to the way castings where done at the time it would create a hard skin that when machined could cause weak points. Letting the blocks sit out to season aleviated some of this problem. However modern casting processes are more refined due to better casting and heat treating.

Have a read
http://www.practicalmachinist.com/vb/general-archive/seasoning-cast-iron-87355/

The most seasoned block it still one out of a higg milage car that has seem as many heat cycles as possible. Hence why bmw used 2002 engines for their high power turbo motors

[mr_hyde]

The most seasoned block it still one out of a higg milage car that has seem as many heat cycles as possible. Hence why bmw used 2002 engines for their high power turbo motors

That's interesting if not counter-intuitive.  The best candidate for us to build a block would be a '94 1.8 with 400,000 daily driver miles provided it wasn't too cut up.  Common intuition would tell you a brand new OEM casting would be best.  Thanks for the link.

[scotty b]

The best candidate for us to build a block would be a '94 1.8 with 400,000 daily driver miles provided it wasn't too cut up.

If that were true, though, automakers would probably buy back blocks on cars getting scrapped and then charge a premium on the special edition cars they put them in.  Yes, some things get better with use (I once read how '50s era Soviet tank engines would grind off pounds of metal when brand new, and ran better afterwards), but nothing mechanical gets better forever, and nothing can withstand stress forever.  I would expect that after 5k or 10k miles a block is the strongest it will get, having seen quite a few heat cycles and before the inevitable forces (like pressure from combustion) acting upon it have had time to really take a toll.

[CharlesE]

Hmmm......My engine has about 170k miles on it.  If anyone would like to pay a large premium for the stress relieved block, please let me know.

[mprhead5]

Well im sure there is a limit to the effect. Im not saying it improves forever but its fairly well documented that older block are sought after because they are believed to be stronger after many years of service.

BMW wouldnt have used old 2002 engine blocks for their F1 turbo motors if it wasnt true. Although since most new engine blocks are aluminum this practice is pretty much in the past.

Interesting side note. I read that a ton of the megatron motors got stolen from a warehouse and ended up in the hands of a dutch company  that was selling them for as low as 10k before they got caught.

['95MSM]

Back when Indy had mechanical variety and was worth watching, stock blocks were often given more boost.  One of the notably fast cars had a block pulled from a school bus.

[mprhead5]

And here we are thinking 20 psi is a lot of boost lol

[scotty b]

And here we are thinking 20 psi is a lot of boost lol

It's all about perspective.  The Saleen S7 Twin Turbo only ran 6.5psi from the factory, but made something like 700hp.  Imagine that 7.0L racing derived V8 running 13psi like a lot of MSMs do!