Improved Racing LS Engine Oil Cooler Bypass Cover for Gen III/IV Small-Block – No Sensor Ports, FKM Gasket

The Improved Racing Gen III & IV LS Engine Oil Cooler Bypass Cover (No Sensor Ports) permanently seals factory oil cooler openings and restores high-flow internal routing for LS small-block pans without an external cooler.

If your GM Gen III or IV LS engine doesn’t use the stock oil cooler—or you’ve removed an external cooler—this billet bypass cover replaces the original diecast part to prevent leaks and improve oil circulation. Machined from durable material and supplied with a bonded high-temperature FKM rubber gasket and hardened fasteners, the cover is engineered to fit most LS-series small-block oil pans where the cooler ports are situated above the oil filter.

How does this bypass cover restore reliable sealing on LS oil pans?

The cover uses a precision-machined sealing surface with a bonded FKM rubber gasket that resists heat and oil degradation. That combination creates a leak-resistant joint without needing additional sealants, while the included class 10.9 mounting screws ensure consistent clamp load over repeated service intervals.

• Aluminum-bonded high-temp FKM rubber gasket for durable sealing
• Precision-machined flange for accurate fitment to pan ports
• Class 10.9 hardened screws supplied for secure attachment

Will this cover affect oil flow compared with the original diecast bypass?

Yes — the internal cavity is ported larger than the OE diecast cover to reduce flow restriction. By offering a less restrictive path, the cover helps preserve proper oil circulation in engines not using an external cooler, while maintaining pressure stability under normal operating conditions.

• Large ported internal cavity minimizes flow bottlenecks
• Designed specifically for LS Gen III/IV port geometry
• Maintains OEM-style routing without added plumbing

Which LS engines and oil pan layouts are compatible with this part?

This bypass cover fits most GM Gen III and Gen IV LS-series small-block oil pans that have the oil cooler ports located above the oil filter. It is intended for installations where no external oil cooler or cooler sensor plumbing is present—the unit does not include sensor ports.

• Compatible with many Gen III and Gen IV LS small-block pans
• For pans with cooler ports above the oil filter only
• Not intended for pans requiring sensor ports or external cooler plumbing

How simple is installation, and what hardware is included?

Installation is straightforward: remove the factory cover, clean mating surfaces, place the bonded gasket and tighten the supplied screws to torque specs. The package includes the bypass cover, a pre-bonded FKM rubber gasket rated for high temperatures, and class 10.9 mounting screws for a reliable assembly.

• Includes pre-bonded aluminum/FKM gasket—no additional sealant needed
• Class 10.9 mounting screws included for consistent clamping force
• Basic hand tools and torque wrench required for proper install

Who is this for: This Improved Racing bypass cover is aimed at LS engine builders, swap installers, restomod shops, and performance enthusiasts who have removed the factory oil cooler or are running engines without external cooler plumbing. It’s suited for anyone wanting a robust, leak-resistant replacement to the OE diecast bypass cover that improves internal oil flow without adding complexity or sensor ports.