I didn't realize what I was looking at the first time I saw it and that was during the rebuild of a .030 over, stock crank, stock rod engine that was probably making between 500 and 600 hp...it wasn't until I had the engine back in the car that a buddy at the track ask if my main caps were walking...???? ...oh well they were still bouncing when I took it apart about 500 passes later... ...after that I started making more horsepower, added studs...then aluminum caps and studs...still bouncing/walking caps... I guess it's just something to live with until I install a girdle, cross bolt it of buy an after market block...