Guys I have a M60 that I am building up to put in my car. I got a great deal on a M60 with the Nikasil block and I just expected to buy the Alusil block from the dealer. But before I buy the block from the dealer I have a quick question for you all. Can I just get the Nikasil block sleeved if I am building this motor to 400+ hp?? Or would I be better off getting the Alusil block and sleeving that? Thanks for your help.

They talk some about sleeving in this thread:

http://forums.bimmerforums.com/forum/showthread.php?t=288073

From what I gleaned, it is very possible, but the cost involved is rather high. Plus, just because it's Nikasil doesn't mean it is bad. If it passes compression testing, it should be fine for use with today's gas. America switched to low sulfur gas back in the late 90's, so pretty much all the blocks that were going to blow have done so. (much to their owner's chagrin) Case in point, my Nikasil block is still going strong, and I'm at 125k miles. Come to think of it, a BMW dealer should not even sell the Nikasil block. If it's an Ausil block, the need for sleeving is questionable, based on my limited knowledge on sleeving.