Originally Posted by conv90
Is there a specific side where the lifter hole should be in respect to the lifter bore??
(Hyd lifter in a roller block).
I know that it should be the same... but I remember also that someone one time said that there is a preferred side to put the lifter in the bore.
In all reality it does not matter. When the SBC was desgined it used flat tappet lifters which rotate in the lifter bore, so the lifters oil supply hole is constantly in a different location as the engine runs.
However with some roller lifters (which do not rotate) I do have a prefered method (for reason's I'll explain below) and it depends on the lifters.
Some roller lifters have the oil feed hole on the same axis as the lifter oil galley in the block. In this case I put the oil feed hole in the lifter facing the rear (bell housing)of the engine. In a SBC oil runs from the pump up the rear main cap and out to the oil filter . From the fliter it runs to the main oil galley located at the rear of the block. From there oil travels from the rear of the block to front of the block. With the lifter oil feed holes facing the rear of the block you put them in the direct path of their oil supply.
Other roller lifters have the oil feed hole 90* to the lifter oil galley in the block. In this case it really dosen't matter because you can't install them in a manner that directly intersects the oil flow.... but just so they are all the same I put the lifter oil holes facing each other towards the center of the block.