I I'm loking to build a ls race motor have found a few 6.0s but dont know how to determine what they are one is a bare block with messed up crank rods pistons and 317 heads no idea what year or block next is a iron head 6..0 and the other is a 07 engine code k in the vin trying to figure out witch one would be the best choice for a 408 build could I refresh the iron headed motor and put the 317s on with a mild cam and have a peppy replacement for my tired 5.3 in my dd or should I look for one with better heads to begin with

 

317's come on an LQ4/LQ9. Which is an iron block 6.0 with a 4in bore. If you want to shave weight, you should find an ls2 block or something that is aluminum.

 

You can use the iron headed motor with a 80e trans with out issue. blocks are all the same as far as i know. Just need to do a set of heads,.

 

Try to find a 6.0 built after 2001, the piston rods in the older ones are weak and don't hold much added power. If these motors don't have years listed or are unknown, I honestly wouldn't bother with them. When I got mine I personally went and watch them start it in the Esky, and came back like 4 hours later after they got it out. That way there was no question.

 

The LQ4's with the best rods are 2005+, with the full floating pin design. Some guys have 04's with them but that is hit or miss at best. LQ9's 2003+ for sure..... some 2002's still had the pressed pin rod.