Special Engine S961 1997 2.8 - Alumasil or cast iron block?

[Mijnagol]

What the title says...When I decoded my VIN I got the code S961, which basically means a U.S. spec 2.8. I am new to BMW's and in my reading on the Nickasil/Alumasil/Cast iron block problems from the late 90's I can't seem to find a definitive answer to something. I have a 2.8, built in January of 1997...so do I have a cast iron block or an alumasil block, and if its aluminum, does it have cylinder liners or not? Just curious as I have found threads on this and other forums with all sorts of "opinions" but I would assume someone actually knows the answer. It seems that early 6 cylinder M52 Z3's had aluminum, but I have seen other opinions...anyone know for sure or got a source?

[328 Power 04]

You have the aluminum block.

Also, a magnet around the exhaust manifold side can check that quite quickly.

[BimmerBreaker]

All Z3 non-M 6 cylinder engines are aluminum blocks

[BladeRunner919]

If you are trying to find out because you're worried about Nikasil, then don't be. The fuel that caused the problems is long gone, and any engines that were going to be affected would have done so years ago, and been replaced. I have a Jaguar with a Nikasil engine, and they are probably actually better than the cars with steel liners.

[BimmerBreaker]

Oh yeah, Nikasil was only a V8/V12 thing. All 6 cyl aluminum blocks were Alusil

They overheat if the coolant gauge looks at em wrong though - that's their main reliability issue

[Mijnagol]

If you are trying to find out because you're worried about Nikasil, then don't be. The fuel that caused the problems is long gone, and any engines that were going to be affected would have done so years ago, and been replaced. I have a Jaguar with a Nikasil engine, and they are probably actually better than the cars with steel liners.

I understood the I6 weren't made from nikasil, i was just curious as to whether the early 2.8s in the US were aluminum with no sleeves or sleeved cylinders...I even found a thread in this forum that said they were cast iron, but I think they were confusing the rest of the BMW line with the Z3 blocks...evidently the z3 blocks were made in a new factory and could be produced in the aluminum easily so they were, but seems to be some confusion as to whether sleeved or unsleeved...so just wondered from an engineering perspective. Thanks for all those that responded.