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Hey guys, I have been looking around lately at buying a forged LS2 short block to swap into my 2004 Z06. I recently finished by build and am making way more power than I expected on the stock LS6 bottom end, 829 / 747 at 13 psi.
Here is my build list: A&A V3 Ti with 3.6" pulley 80# Deka injectors 52mm Turbosmart BOV NGK TR6 plugs 2 bar MAP sensor IAT sensor spliced post MAF
ATI stock sized balancer - pinned ARP crank bolt Katech C5R timing chain C6 PS pulley Melling 10295 high pressure oil pump (red spring / black o-ring)
Dewitts cut down radiator / cradle at stock height SPAL fans Stock thermostat
LG pro long tubes 1 7/8" with catless x Borla stingers
ECS diff brace Mantic twin disc ceramic with lightened steel flywheel Hurst short shifter Antivenom mod New TOB New stock slave cylinder AEM wideband Autometer boost gauge
Air pump delete / exhaust block off EVAP delete from driver's intake manifold
Vibrant vacuum block to T fitting in brake booster (2 lines to external fuel pump hobbs at 4 psi / 7 psi, 1 line to BOV, 1 to boost gauge, 1 to alky meth kit)
New fluids (diff / trans / oil / clutch / PS) New intake manifold gaskets New valve cover gaskets New water pump gasket New front timing cover gasket New rear main seal
I have considered several options including just sending the LS6 block for a forged rotating assembly, but thought the added cubic inches would be a plus since I'm pulling the motor. Based on some searches, I think the LS2 would be the way to go. I do not want to replace a bunch of items that I recently bought and would hope they transfer over to the new block.
Can I reuse my stock LS6 243 heads and intake manifold on the LS2? Would my LG long tubes fit clearance wise with the new block? Also does the LS1/6 ATI balancer fit the LS2 crank?
What compression should I aim for with 13-14 psi?
Finally, could you tell me what modifications would be required to make this motor fit (tap for knock sensors, relocate cam position sensor, new cam cover, grind bracket near the engine mount, etc...)? I would plan to buy everything new with a 24x reluctor wheel and not run a Lingenfelter box.
I was under the impression that the LS3 swap required more modification? I might be wrong here. If they are the same in terms of swap, I would definitely consider the LS3.
Also I’ve heard using the LS6 top end on the LS3 block will create higher compression and isn’t ideal whereas the LS2s used the 243 heads.
Is there anything that needs to be changed in terms of the 2004 PCM with either of these motors other than the usual tune after swapping?
Last edited by pianoman90; Mar 19, 2023 at 05:52 PM.
When you pull the LS6 short block I am highly curious what the rod bearings look like. Especially on the rod end (where the piston would be pushing down)
When you pull the LS6 short block I am highly curious what the rod bearings look like. Especially on the rod end (where the piston would be pushing down)
Forged LS2 swap
