isnt there differnt letters or series with them whats teh difference in them i hear the h series ones are the best but im having trouble even finding which main bearings i have they say MB 2122H and the other half says MB2121H , then the rod bearings say CB 1227p i cant seem to find those exact ones either anyone have any clue though which ones are the better ones to run as far as series and if you can identify those it would be awesome thx.
