how much can you safely bore a lq4 block

 

.060 i think

 

.04 is the most I would do need to get it checked to see if it can go anymore after that

 

so you can't take it to 4.125

 

Its going to be iffy it will require testing the block and retesting it after each .005 or so is bored out of it. Im going to try it with the 418 block when I pull it back out this summer if I do and try and get the most out of it possible then order pistons to match my bore. Mjhoward did some quick measurements on my block and he said he "thinks" it could be done on the 6L in his garage or mine cant remember which one it was that he checked and it would "probably" bore out to 4.125 but I wont know for sure till I try it. Like I said Im going to bore it as big is at will go and then we will know for sure how big a 6L block can really be bored. You also need to take into account casting imperfections some cylinder walls are thinner than others too.

 

yeah so it will probably cost alot in machine work huh.

 

GM sleeves the 427 which has the 4.125 bore. I've read that the 6 liter only goes 30 over but that's hard to believe. But what the hell..... sleeve it if you want cubes!!!!!!!!!!!! If you can afford to buy 4.125 pistons and a 4" stroke and ??????? other parts you can put a couple bucks in sleeves HUH? Love them cubes.

 

Jim the sleeved block you are referring to is the C5R block which is aluminum with iron sleeves in it. The LS1 block can only be bored over about .01 safely some ahve done more but not recommended at all. Thats why they sleeve the aluminum block its lighter than a cast steel one and can be jsut as big. Thats why I think the 4.125 bore is pretty possible with a iron 6L block we will find out for sur this summer if no on ebeats me to it and I pull the motor. Im never going to be satisfied with how my motor runs so I will continue to pour more money into Im sure until it comes time to get a house and all that good stuff after I graduate college.