M50 stroker build

[huyatgr]

I think I'm actually serious about going through with this. I've been looking for a new project, and I've wanted to build an engine, so this seems like the perfect idea, since it won't be that hard and relatively cheap for an engine build.

The compression on the M50 checked out great - 240 psi all across. The guy might actually have been honest when he said it has 60k. I'm hoping to pull it out of the parts car this weekend if I have time.

The reason I made this thread now is because I need to know what to look for as far as the M54 rotating assembly. I'm hoping to spend about ~$500 on the M54B30 crankshaft, rods and pistons. I'm not sure how to tell if it's good or not though. How can I check the bearings? And I'm guessing I would have to get the piston rings measured to make sure they are good? I'm hoping to get help from a local BMW shop for actually swapping the internals, but I need to find the parts myself. Is it risky to buy the block from an overheated M54? Any things that I should check?

I think that's all the questions I have for now, but there will probably be many more coming.

[Jack Dabsy]

The block should be fine as its only the top-end that gives way under overheating conditions...
If you're serious about the build then drop the crank (numbering the bearing-shims and caps) and notice shininess and make certain the bearings have not spread/flattened slightly, if there is any scoring then that item and its friends should be replaced and the crank re-grinded !!
Draw the cons/pistons and have a look at any "scoring" to the rings and liners.
By doing this you can also clean the oil-pump/strainer etc giving you peace of mind....
HTH