Originally Posted by COPO9560
If you already have a LS3 block, dry sleeves are your cheapest option. If you have a LS1 block, only option is wet sleeves - more money but stronger build.
Take a look at ERL's website - many options to work from.
Least expensive option really depends on what you have on hand. If you have a complete LS1 engine, covers etc it will be less overall to wet sleeve this versus buying new LS2/3 block, covers etc and dry sleeving. Short block is one thing - 4.125 bore opens up a lot of great but expensive head options. Overall a fantastic engine can be built but it will be costly to complete. Need to ask yourself if the gains over 408 are worth the cash you will have to pay.
I do not have a block yet. I was planning to go LS3 but I really wanted to maximize cubic inches with out running a long stroke. The LS7 block is way too much $ for me.
I've seen some aluminum 5.3 blocks for sale on Ebay cheap. Not sure if they would be a good candidate. What is the max bore size on the 6.2 block using wxisting sleeves?