109 Main and rod bearing tolerancing

[vacuum 6]

Both mains and rods should be .0015-.0020”

On a mid 10 sec engine you can run looser rods. How much more can you open it up? The car will be street driven.

 

[turbofabricator]

I shoot for a clearance of .0017-.0019 for both rod and mains. If running more than 700 then open them up to .002" The key word is "shoot", as it is not always possible to get a perfect clearance. Engine building is a compromise. I mix and match bearing shells to try and get the target clearance. A good machinist will make your assembly job easier. Find one and keep using them.

 

[vacuum 6]

Thanks Ken. Should be easy to target