tsteinmetz53

Does anyone know of anyplace that stocks the 2nd overbore piston for an MC engine. I am planning on doing an upgrade to my urquattro, already bought the motor/rods/bearings/etc. and now the machine shop tells me that the pistons are no good. Any help would be greatly appreciated.

gmbchef

Did the shop give you specific measurements? When I had mine measured, i went through the specs with him. The pistons and cylinders were worn, but still within spec.
HTH

tsteinmetz53

the shop gave me the specs - he said the pistons were ok but the block was too far worn.

urq20vt

Apparently they end up with a lot of taper, requiring boring and new pistons and rings. This work is not cheap by any means. The correct Mahle pistons are ~$100+/each as I recall. Factor in bearings (AAN for durability), machine work, etc. and you can hit $2k on the bottom end.

audiurq

When I had my 3B rebuilt (the engine had 250K miles) it needed a re-bore but I couldn't find
over sized pistons. I ended up using the
original pistons and having liners installed
in the original block. You wouldn't know that
they are there when you look at the top of the
block. You might want to ask your machine shop
if they do this?

Cheers, Mike

urq20vt

I was quoted $40 a cylinder by reputable shop here a few years ago.