
OVERVIEW
Improved Racing designed this billet aluminum rear oil passage diverter (also known as the "barbell") for Gen III and IV GM LS series engines to improve oil flow and completely eliminate dirty engine oil from bypassing the filter. This part is an improvement over the plastic OEM diverter plug at a similar cost and is a perfect replacement in any engine build.

Improved Racing's oil diverter plug features a second O-ring that completely seals off the dirty oil from the clean oil, ensuring no dirty oil bypasses the filter. Sharp corners were avoided and machined as smooth fillets to improve oil flow, while the bullnose tip helps smooth oil flow to the oil filter. The shaft diameter is smaller than the OEM plastic barbell to minimize flow restriction. A threaded hole was added so that the barbell can be easily removed with any M4x0.7 screw.
How Does it Work?
Features and Benefits
- Direct replacement for plastic OEM barbell plug.
- Precision Swiss CNC-machined from billet 6061-T6 aluminum.
- Designed to reduce fluid restriction and maximize oil flow.
- Second O-ring completely seals the dirty side of the rear oil passage from the clean side, preventing dirty oil from flowing to the engine bearings.
- FKM (Viton®) rubber O-rings are used for its ideal compression set (for a long-lasting seal), high temperature resistance, and excellent chemical compatibility with engine oils.
- Threaded M4x0.7 hole allows for easy removal from engine block.
- Made in the USA.
- Lifetime Warranty.
Includes
- 1 x Swiss CNC-machined billet aluminum rear oil gallery plug "barbell."
- 2 x AS568 Dash Number 111 Size FKM (Viton) O-rings.
Applications
- Do not use with the LSX engine block. These engine blocks have a slightly different oil passage and use a rear cover design that will result in interference with the oil passage plug, resulting in leaks.
- Compatible with most General Motors Gen III and IV LS series Engines (including Vortec truck engines), except the LSX block.
| Part # |
EGM-501
|
|---|---|
| Primary Material |
6061-T6 aluminum
|
| Finish |
Plain
|
| Color |
Natural
|
| Brand |
Improved Racing
|
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