Pre Stage Block

[Bakn2Gns]

I have a line on a block I’ve never heard of. It’s a pre Stage Block although stronger and beefier than early production blocks. Possibly a 4.1L with two center 4 bolt main caps. Possibly has an x in the casting number. I’ll know more soon but any info would be a great help. I can’t seem to find much on this early pre Stage Block. Thanks!!!!

 

[750H.P.V6]

If you have a copy of the Buick Power source manual it seems to me there are a couple pictures of Stage II blocks that aren't off center blocks. They appear to be of an earlier vintage. There were heavy duty blocks cast that per-date the Stage I and II blocks. If you end up getting it post some pics it would be cool to check it out.

Neal

 

[Spooln1]

I also have an X block that is currently being built. I don't know if it was pre stage 2 stuff or during as an experimental testing for the Buick race teams. Its an on center block with all 4 bolt caps. I'll try and post some pics here to reference.

 

[750H.P.V6]

4X castings were pre-production parts. There were quite a few as the Buick Motorsports program progressed thru the years. The block that the OP was asking about would be much earlier. If it really is a Buick H.D. block which pre dates the Stage blocks it would be from the late '70's possibly very early '80's. I still want to see pics.

Neal