For Sale: Pair of Bare GM 243 LS Cylinder Heads

Up for sale is a fairly clean matched pair of genuine GM 243 casting cathedral port cylinder heads. These are the desirable heads commonly found on LS6, LS2, and many 5.3L/6.0L Gen III/IV engines. They are completely bare (no valves, springs, retainers, or rockers) and have been thoroughly cleaned with an aluminum-safe degreaser.

Key Features:

OEM GM 243 castings

Cathedral port design (great for LS1/LS6/LS2 performance applications)

Combustion chambers, intake/exhaust ports, and valve guides appear in good visual condition

Heads have been disassembled and degreased for a much cleaner appearance than typical used LS heads

All visible passages and surfaces look solid with no major cracks or heavy corrosion

Condition Note (Important - please read):

The only issue is one broken exhaust manifold stud on one head, with a small amount of aluminum material missing around the broken stud. This is a very common occurrence on LS aluminum heads due to the design and heat cycling of the exhaust bolts/studs. The rest of the head (including all other manifold bolt holes) is intact and undamaged. These heads are otherwise ready for machining, valve work, or porting as needed.

These would make a great base for a rebuild, porting project, or direct replacement on an LS1, LS6, LS2, or compatible 5.3/6.0L engine. 243 heads are popular for their relatively good flow and smaller 64cc combustion chambers compared to earlier 241/853 castings.

Buyer responsible for any additional machine work, valve job, or repairs needed for their specific application. No core charge — these are sold as-is.

Shipping:

Heads are heavy — please expect realistic shipping cost based on your location.

I pack carefully with plenty of protection on a pallet or reinforced box if needed.

Local pickup available in the Jefferson City, Missouri area.

Payment: PayPal or eBay managed payment. Payment due within 3 days of auction close.

Returns: No returns accepted due to the nature of used automotive parts. Please ask any questions before bidding/buying.