rebuild turbo engine from NA bare block

[911tracker85]

I need to rebuild my 951's engine. pulled head to replace head gasket and found very bad scouring on #2 cyl.

been searching for a 951 bare / short block.

I have read references to using a NA block, and basically understand the need to drill / tap an oil port on the intake side balance shaft cover.

I read that the BS covers must be a match for the block, but not sure if that is the case in later blocks with BS bearings as my 87 block has.

cant find a more detailed explanation, anyone know of a thread that explains what / how to do this?

[kdjones2000]

The later blocks (like the one shown) has the bearing bridge integral to the balance shaft cover. The '86 and earlier engines have separate covers and bridges.

The later ones are align-bored and therefore matched to the block, as are the bridges in the early blocks.

The cover itself on the early blocks may be possible to swap among blocks, but I believe that the workshop manual still states that they are matched to the block.

Look in your workshop manual for more information on this.

[DannoXYZ]

The '86+ NA engines have oil-port already in place for turbo. It's just blocked off with a plug.

[911tracker85]

The '86+ NA engines have oil-port already in place for turbo. It's just blocked off with a plug.

thanks I had found some info that suggested this but not sure.