After some core shift issues I have experenced with the mopar 340 siamese replacement block P5153478AB, I have located a 318 Magnum P5153579 with a finished bore of 3.910". Before I outlay more cash I was wondering if anyone has played with/or has more info on this P/N block. Am I correct in saying that all 59 deg siamese blocks are of the same casting and just finished differently in the bore size and in the main tunnel for 360 Mag block. If this is the case one would think that there would be plenty of material to play with if mopar state max bore 4.220?????
And can you use standard LA oiling to the heads with this P/N block?

Thanks in advance
Macka