Quote:

4 bolt mains don't mean anything unless they are splayed and doweled. thats the only way to keep them from moving around. the BBC merlin blocks with ductile iron caps without dowels have cap walk too. as i said before, splayed and doweled is the way to go. we routinely see merlin and dart blocks holding up to 1800-2200 HP without cap walk. don't you wish a mopar block would do that.
if it's worth doing it's worth doing right. don't skimp like MP did and have a heavy iron block that still has issues. it would be a waste of time and money in the investment and the same for the end user IMO.


You hit the nail on the head with the 'doing it right' statement!
I agree that the splayed bolts help keep the caps from moving as do the dowels, but from what I've seen, they are only keeping the bottom of the cap from moving and transferring metal, the rest of the cap is still having to deal with the harmonics which is why it's no surprise that I feel a girdle(in conjuction with whatever main cap you choose) is the only way to fully stabilize the bottom end on a BBM. The aluminum caps seem to dampen the frequency a little better than steel and iron, and are softer giving little or no signs of transfer, but I'm not a fan of aluminum caps on multi climate street cars. JMHO..