Boost on a 427 darton?
Keeping the heads down is the problem, not the sleeves. A good thick deck head will help as will APR studs. What's the limit on the amount of boost you can run? I don't know, but I wouldn't think 16 psi would be a problem at all... anything over that you get into that grey area as with any of the LSx blocks.
From what I understand, the wet sleeves are superior to the dry sleeves... the down side is the cost. If you have the money, a LS6 Darton sleeve 427 is a tough combo to beat if you don't want to go with an iron block.
what Wet1 stated is correct. the import guys with the b16 blocks and nisan guys with the vq35's (350z motors) and viper guys are running boost amounts to put them in the 1000-2000rwhp range.
bottom line is the darton sleeves will handle more then what you can think off. just have the block done by someone who is qualified; Steve is the man. if not, hit up Howard Wolf.
i'd be worried about keeping the heads down and my fuel system before i worried about a darton block.
for an all out boost/n20 motor the wetsleeve is the way to go. for a street/strip motor i'd look into the darton LS2 dry sleeved blocks. it'll run you a couple hundred bucks less. you cant beat an aluminum block with 4.160 capabilities for under 3k.
with the iron blocks your limited to .080 on a rare sonic tested block, .030 for the common 408. the darton sleeves will go 4.160 on both the wet and dry liners. the 4.200 sleeves should be out shortly.
Greg



