Ls2 Heads On My 5.3

doubl3you · February 7, 2009

i just got a set of ls2 heads off of an 05 t-blaze ss. (we did the 6.2 head swap on it.) and the cam as well. i was just wondering if anyone has done this swap or if im going to have to go at this alone? i was wondering what all i was going to need. i have.........

complete heads

lifters

pushrods

cam

intake manifold

i know i have everything i need except for things like the intake manifold gaskets, head gaskets and such.

any help would be apreciated.

Ryan00TJ · February 7, 2009

The LS2 heads are probably #243 or #799 castings. Both have the same below specs. The heads used on the LS2 do not have the sodium filled valves, just 24N stainless. They should be a nice improvement over the stock 5.3L heads you currently have. The stock LS2 cam is a tad more aggressive than your stocker but for all the work involved of the swap, I would put in something more aggressive. Something in the 210-220 range with .550+ lift on a 110+4 LSA. Strong lowend and midrange with decent topend without having to rev much past 6000rpms.

BTW... 07+ 5.3L's come with them stock.. Mine has the #799's.

243

Heads: 2001+ LS6 5.7 liter passenger car

Material:Aluminum

Part Number: 12564243

Combustion chamber Volume:64.45cc

Compression Ratio:10.5:1

Intake port Volume:210cc

Exhaust Port Volume:75cc

Intake valve Diameter:2.00-inches

Exhaust valve Diameter:1.55-inches

What you need to know:

The LS6 cylinder heads is essentially a tuned-up version of the LS1 head. At 65cc, the combustion chamber is slightly smaller and more efficient than the LS1. The more efficient design shortens burn times and ultimately means less ignition timing advance is required to produce the same power. And because less timing allows more efficient combustion, the Ls6 heads allow the engine to produce more torque. The exhaust port is a unique D-shape that improves flow. LS6 heads are the best choice only when all-out power is needed. Be prepared for a big price tag at the dealer or steep core charge from your head porter.