400 B block
www.pro-gram.com for steel 4-bolt main caps
http://stankemotorsports.com/ for aluminum 4-bolt main caps for big block Chrysler
[ame="http://www.ebay.com/itm/261190453435?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT#ht_90wt_1153"]383 400 440 Chrysler Mopar Side Bolt Billet Aluminum Main Capes | eBay[/ame]