Stage 1 or 2 ??


Oct 27, 2003
I found a 4.1 00016 Stage I virgin block that has all billet caps (4 bolts on the center two with splayed bolts) and 6 boltholes per cylinder. What's the difference between this and an actual Stage 2 block? Thinking of purchasing this block.
Someone will correct me if I'm wrong, but the last I remember is that a 016 block is a Stage II, not Stage I.
And what you describe is a STG II. I.E. four bolt splayed center caps and 6 bolt/stud head bolt holes.
STage I blocks have the provisions for 6 bolts per cylinder but don't come machined that way.
I thought this might have been a Stage I block that some had converted by installing all 4 billet caps w/ bolts and machining the extra bolt holes for the cylinder heads. Either way, is there any difference now? Thanks.
Yes, If is realy is a S1 block the oiling will be different.

S1 and S2 blocks are made from the same casting and that is why both blocks have the 016 casting number. S2 blocks had the oil pump pickup machined at #1 main and the oil feed galley to the lifters doesn't run thru the lifter bores...just outside the lifter bores.

S1 blocks have all production oil provisions with the oil pump pickup at #2 main.

All S2 blocks got 4 bolt #2 and 3 main caps. Early 016 blocks had production cast #1 and #4 caps and steel #2 and #3. Later blocks got #1, 2 and 3 steel caps and #4 cast. The last 016 block got all 4 caps in steel with BBC rear main seals.