Main cap girdles re-discussed

gagembassett said

I was just rereading a thread I commented on a long while ago about main cap girdles and the ending consensus was a no..... HOWEVER I did read it and it seemed to me that everyone was only implying it to 2 bolt main girdles on an LA factory block. Now I do understand that some people still run 4 bolt caps and leave the outer bolts unused just to help transfer the stress across a more broad surface area. So my question is what does everyone think about running 4 bolt caps for that and adding a girdle on top? Yay? Nay? Why?

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Rover found fretting on the Aluminium blocks under the main caps. This was the reason that Rover went to cross bolted mains. Originally designed by the General with two bolt mains. I do not know how the Buick/Olds blocks stood up in that regard. I have one on an engine stand but not ready to tear into it yet. Would seen to be a prime candidate for a main cap girdle.
Back to the Mopar question, IMHO it would depend on the build. If building a somewhat mild engine, then a girdle is not needed. However if building a boosted engine or intending to wind it to the moon, a girdle would be advised. In that case, hardened washers under the inner bolts of a four bolt to allow a girdle to clear the outer bolts will not do any harm. There is David Vizard's 100pHP Ford block Youtube to watch that discusses the issues. Another is I think Unity Motorsports Garage Youtube that compares the SBC, SBF and SBM blocks and compares strengths, weaknesses and a quickmention at weight. Combine the information to get an idea of how to proceed. I noticed an UTG header for one of Tony's episodes that hints at a design flaw. Let'a face it, all the manufacturers have their strengths and weaknesses. For the most part the American engines have been pretty good designs, but they all have put some crappy ones out.