Description
This kit includes everything needed to cap a rear LS steam vent port: the billet aluminum plug, mounting screw, and port o-ring.
Why Steam Ports Matter
GM’s LS steam ports exist to bleed trapped air and steam from the highest points of the cylinder heads, the same air pockets you’re chasing when you burp the cooling system during a fill or after service.
Left trapped, that air collects at the back of the heads and creates hot spots that raise the risk of detonation and uneven combustion across cylinders.
Features and Benefits
| Easier cooling system bleeding | Purges trapped air pockets from the back of the cylinder heads, key to a properly bled cooling system. |
| Prevents hot spots | Air pockets in the back of the heads create hotter cylinders prone to detonation and engine damage. |
| Safer, more consistent tuning | Uniform cooling across all cylinders allows a safer, more aggressive tune without sacrificing horsepower. |
| Reduced detonation risk | Eliminating trapped steam prevents detonation and other combustion issues caused by uneven cooling. |
| System reliability | Venting pressure from the engine’s highest points keeps the cooling system working as designed. |
