6.0 Swap - NEED HELP ASAP!!!!

**SkreaminHawk** · 12-17-2006, 02:03 AM

Ok, so I finally got my Firehawk done away with for the most part, and waitin to make arrangements to get the headache gone. I'm starting my 99 Z buildup and I've got a junkyard LS1 and a 6.0L LQ4 (LQ9 maybe?), and am going with a budget buildup in a wrecked LS1 Z chassis car. What I need to know is this. Providing that the pistons and rods and bearings are still good in my LS1, can I use the factory 6.0 crank and mate with the rods and bearings with the 5.7 LS1 or no? If not, can I take my 6.0 Crank/Rods/Bearings and use them with the 5.7 pistons and wristpins and mate them all together? If not, my 3rd question is this. If I use my 6.0 shortblock, should I use my 317 heads or should I use my LS1 heads. I know the 6.0 heads flow more but the compression is lower, therefore, resulting in a loss of horsepower. But, if I use the LS1 heads with my 6.0 head gaskets, will I see any kind of performance difference than using my 6.0 heads? And if so, what EXACTLY would the difference be? Just a few particular things I need to know. Thanks for all the help guys, I sure do appreciate it!!

~Jonny

**SkreaminHawk** · 12-17-2006, 02:06 AM

I forgot. Also this. Which would run better with a 99 factory tune (factory wiring harness and all), the LS1 heads on the 6.0 shortblock or the 6.0 heads on the 6.0 shortblock? Either way, I'm using the factory 99 model year .500"/.500" lift cam and factory intake. Thanks a bunch!!

~Jonny

**9T8W66** · 12-17-2006, 07:00 AM

Everything (crank rods bearings( is the same except the pistons between the 2 shortblocks. You should be able to bolt up the LS1 heads and see a compression boost. you should look into getting maybe a Hotcam and LS6 intake to accent your extra cubes. Either way you would need a tune to see the best performance.
You also may need new front springs because the 6.0 blocks are heavier (Iron vs Aluminum)

**12secSS** · 12-18-2006, 08:33 AM

Do not just swap internals from the 5.7L to the 6.0L or vice versa, either way you will need to rebalance everything. The 5.7L is balanced for lighter piston then a 6.0L, so if you use the crank and rods from the 6.0L in your 5.7L pistons, it will be catastrophic and have vibration issues. Just use the 6.0L short block as is. I would actually use the 6.0L long block, what heads are the LS1 (853, 806, 241)? If anything other then 241, I would use the 317 6.0L heads.