4 bolt main conversion? Or 2 bolt main stud girdle?

Both options seem legit. But in my mind they do different things, kinda… seems like the girdle add rigidity to the caps from walking back & forth while the 4 bolt main keeps the cap clamped tighter to the block.

I Would Rather a Splayed 4 Bolt Conversion. Those get Pusback also I believe from some Builders.

2 Bolt Blocks are Pretty Tough as is Though.

A Factory 4 Bolt D0OVE Block Would be My First Go To if I Had the Choice and Could Not Get an A460 Block Though.

nedceifus wrote:Both options seem legit. But in my mind they do different things, kinda… seems like the girdle add rigidity to the caps from walking back & forth while the 4 bolt main keeps the cap clamped tighter to the block.

Some stud girdles are spaced-up from the caps and don't do much except hold the bolts in line.

A stud girdle which actually works at making it stronger requires the caps to be machined flat with the girdle laying right on top of the cap for the entire span.

The Engine in Post #5 in the Below Thread Looks Like The Best Deal to Me, When All is Said and Done, To Run.


https://www.429-460.com/t29067-holley-hi-ram-for-385-series

about the only thing a girdle does in my opinion is keep the parts inside when the damn thing blows up

One of my 460 blocks has 12-13 years of drag racing on it .You can see the evidence of cap walk this a d1 block two bolt main my bearings always look good .My spare d1 two bolt main has arp studs .I ran it 2-3 years bearings look good .But the block and main caps show very minimal evidence of cap walk .No stud girdle the nuts torque to 110 lbs. both blocks have been line honed .That block is now a 502 .My experience is with any two bolt block you will have some cap walk but maybe it isnt the end of the world .In reality pistons rods and 460 crankshafts are heavy so it is going to happen .Four bolt main conversions for a d1 block (or d9) is a tough go and expensive .I just keep my rpms under 6200-6300 so far so good maybe in a couple of years I will pull this 502 out and check it for cap walk I.installed a forged crank in this one most likely it is heavier than a factory crank. Doug