Best Oil Cooler Delete Kit for LS, Subaru and Honda Applications

#1 · Best Overall

1. Improved Racing LS Bypass Cover

• Weight: 2.46 oz
• Package Dimensions: 6.18 x 4.06 x 0.75 in

Best for: LS stock-cover replacement.

Why it ranks #1: Fits most Gen III and IV LS pans with ports above the filter and includes a ported cavity, bonded FKM gasket and class 10.9 screws.

A large ported internal cavity distinguishes Improved Racing’s bypass cover, enabling oil to flow more freely than through the factory diecast cover. It replaces the original bypass cover on vehicles without an oil cooler, while the included bonded FKM gasket and mounting screws support a straightforward, sealed installation.

Fitment is aimed at most GM Gen III and IV LS small-block oil pans with cooler ports above the oil filter, so the location matters when checking whether this cover suits the engine. Its ported cavity offers better flow than the OE diecast bypass cover, while the aluminum-bonded high-temperature FKM gasket provides a sealing surface. Class 10.9 mounting screws are included. This is the no-sensor-port version; a separate version is available with two 1/8-inch NPT ports.

Skip it if you need sensor ports for temperature readings or turbo oil supply; Improved Racing EGM-109 is the listed ported alternative.

A practical choice for LS owners replacing the factory bypass cover on an engine without an oil cooler. Check that the pan’s ports sit above the oil filter, and choose another version if you need sensor ports.

Listed on Amazon as: Improved Racing Gen III & IV LS Engine Oil Cooler Bypass Cover (No Sensor Ports)…

#2 · Best Gasket Kit

2. CNRAQR LS Bypass Cover

• Weight: 5.6 oz
• Package Dimensions: 6.06 x 5.91 x 0.87 in

Best for: Black anodized LS cover.

Why it ranks #2: Its 6061-T6 aluminum cover fits most Gen III and IV LS pans with ports above the filter and includes an upgraded gasket.

A CNC-machined 6061-T6 aluminum body with a black anodized finish sets this CNRAQR LS bypass cover apart, while its large ported cavity targets smoother flow than the factory diecast cover. It replaces OE 12577903 and fits most Gen III and IV LS small-block pans with ports above the oil filter.

This cover targets most Gen III and IV LS small-block oil pans whose cooler ports sit above the oil filter, giving buyers a specific location to check before installation. Its large ported internal cavity is described as improving flow characteristics over the factory diecast bypass cover. CNC-machined 6061-T6 aluminum and black anodizing specify the construction and finish. The listing identifies an upgraded gasket, supporting the sealing role of the replacement cover, but does not provide further gasket material details.

Skip it if you need sensor ports in the bypass cover; this model is explicitly the no-sensor-port version.

A suitable option for LS owners replacing the OE bypass cover with a black anodized billet part and upgraded gasket. Its no-sensor-port configuration is a boundary for builds needing oil-temperature connections at the cover.

Listed on Amazon as: LS Engine Oil Cooler Bypass Cover Block off Plate Compatible with Gen III IV LS Engine Replace OE#12577903(No Sensor Ports)

#3 · Thick Aluminum Plate

3. Podavelle LS Bypass Plate

• Weight: 1.76 oz
• Package Dimensions: 5.55 x 3.46 x 0.31 in

Best for: LS pan bypass plate.

Why it ranks #3: The 6061-T6 plate is 1/2 inch thick and fits LS oil pans, but excludes GTO front-sump pans.

A half-inch-thick 6061-T6 aluminum plate bypasses the oil-cooler feed port to the return port in the oil pan, enabling internal oil routing when cooler plumbing is not being used. Its stated broad LS-pan compatibility has one important exception: GTO front-sump oil pans are excluded.

The plate installs at the oil pan above the filter, where it connects the cooler feed and return ports for bypass plumbing. Its half-inch thickness is described as allowing more oil to flow internally through the engine, while lightweight 6061-T6 aluminum and an anodized finish provide the listed material and corrosion-protection properties. Fitment is stated for LS oil pans generally, but not GTO front-sump pans, making sump configuration a key selection boundary.

Skip it if you have a GTO front-sump oil pan; this plate specifically excludes that pan configuration.

A fit for LS owners routing the oil-pan cooler ports internally and seeking a thick aluminum plate. The GTO front-sump exception is decisive, so verify the pan configuration before selecting this bypass cover.

Listed on Amazon as: LS Oil Cooler Bypass Block-Off Plate for Gen III IV Series Engines LS1 LSX LS3 LQ4 LQ9 LR4 LS6 L33 LS2 LH6 L92 L76 L98 L9H L20 L94 LZ1 L99 L96 LC8 L77 Port Black

#4

4. Saillong LS Block-Off Plate

• Weight: 1.76 oz

Best for: Simple LS sealing replacement.

Why it ranks #4: This lightweight aluminum plate is listed for Gen III and IV LS pans and is intended to replace a damaged or leaking original cover.

A sealing-only role makes the Saillong plate a straightforward LS oil-pan replacement for an original cover that is damaged or leaking. It is listed for Gen III and IV LS pans and is intended to seal the oil pan without modification or added components, rather than change engine combustion operation.

The plate’s stated job is to seal the oil pan and help prevent leakage during LS engine installation, which suits replacement of a damaged or leaking original cover. Compatibility is listed for Gen III and IV LS oil pans, with installation described as requiring no modification or additional components. Its aluminum-alloy construction is characterized as durable and lightweight. Because the plate functions solely as a sealing component, the listing does not present it as a device that alters combustion or engine operation.

Skip it if you want a cover whose large ported cavity is specified for smoother flow; CNRAQR’s LS bypass cover lists that feature.

Choose this plate when replacing a damaged or leaking cover on a Gen III or IV LS pan and a sealing-only part meets the need. The listing does not specify a ported-flow design or other plumbing function.

Listed on Amazon as: Saillong 1 Pack LS Billet Oil Cooler Block-Off Plate, Black

#5

5. Kaas LS Billet Plate

• Weight: 2.08 oz
• Package Dimensions: 2.83 x 2.48 x 1.26 in

Best for: Broad-fitment 6061 LS plate.

Why it ranks #5: Its 6061 aluminum plate is listed for multiple LS engines, including LS1, LS3, LQ4 and 5.3L applications.

The Kaas plate names a broad set of LS engine families and displacements, from LS1 and LSX through 4.8L to 6.2L applications. Its 6061 aluminum construction and stated direct-fit role support oil-pan sealing during LS installations while keeping the plate lightweight.

Kaas lists compatibility with LS1, LSX, LS2, LS3, LQ4, LQ9, LS6, L92, L99, and L33 engines, including 5.3L, 4.8L, 5.7L, 6.0L, and 6.2L references. That breadth helps buyers compare the named engine against the application. The 6061 aluminum alloy is described as durable and lightweight, while the plate’s stated job is blocking off the oil pan to prevent leaks and maintain proper oil flow. A black anodized finish is also specified.

Skip it if you need a cooler-delete part for a Subaru, Honda, or Volkswagen engine; this plate is listed for LS applications.

A relevant choice for an LS installation matching one of the named engine families or displacements, with aluminum construction and an oil-pan sealing role. Its stated application is LS-specific, not a cross-brand fitting.

Listed on Amazon as: Kaas LS Billet Oil Cooler Block off Plate on Oil Pan for LS1 LSX LS2 LS3 LQ4 LQ9 LS6 L92 L99 L33 5.3L 4.8L 5.7L 6.0L 6.2L Black, Aluminum Alloy 6061

#6 · Two-Cover Package

6. TIGYMSD LS Bypass Kit

• Weight: 3.2 oz

Best for: Billet LS replacement cover.

Why it ranks #6: The listing identifies a 12577903 replacement for most Gen III and IV LS pans with cooler ports above the filter and says the package has two covers.

CNC-machined 6061-T6 billet aluminum gives this TIGYMSD bypass cover a different construction from the factory diecast part, while its large ported cavity targets smoother oil flow. It replaces OE GM 12577903 and fits most Gen III and IV LS small-block pans with cooler ports above the oil filter.

The specified port location—above the oil filter—helps narrow the fitment check to compatible Gen III and IV LS small-block oil pans. Its large ported cavity is described as offering smoother flow characteristics than factory diecast bypass covers, making internal passage design a practical distinction. CNC-machined 6061-T6 aluminum and a black anodized finish provide the stated material and surface treatment. The listing identifies a kit containing two bypass covers and four zinc-plated screws, though further package contents are not specified.

Skip it if you need a cover for a pan with cooler ports in another location; this listing specifies ports above the oil filter.

Consider this kit for a compatible Gen III or IV LS small-block pan when billet construction and a ported cavity are priorities. Confirm the cooler-port location against the stated above-filter fitment before choosing it.

Listed on Amazon as: 12577903 LS Engine Oil Cooler Bypass Cover Block Off Plate Kit

#7 · Sensor-Port Option

7. AWL Brothers LS Bypass Cover

• Weight: 3.2 oz
• Package Dimensions: 3.5 x 3.03 x 2.05 in

Best for: LS replacement with NPT ports.

Why it ranks #7: Its title specifies two 1/8-inch NPT ports and Gen III/IV LS fitment, though its key features conflict by describing a no-sensor-port design.

Two 1/8-inch NPT ports are called out in this LS bypass-cover title, offering a defined connection detail for buyers considering ported plumbing. The listing also identifies OE 12577903 replacement fitment for Gen III and IV LS engines and says installation requires no modifications.

The stated Gen III and IV LS application and OE 12577903 reference help identify this cover as a factory bypass-cover replacement. The title specifies two 1/8-inch NPT ports, a useful detail when planning connections that use those threads; the feature text separately describes a no-sensor-port design, so the listing is inconsistent on port purpose. High-strength aluminum alloy and tight machining tolerances are described as supporting durability and a secure fit under high temperatures.

Skip it if you need unambiguous confirmation of sensor-port configuration; the listing conflicts between two NPT ports and a no-sensor-port design.

Consider this cover only if the LS replacement fitment and stated NPT thread size suit the build. The listing conflicts about sensor ports, so that uncertainty matters when planning instrumentation or oil plumbing.

Listed on Amazon as: LS Engine Oil Cooler Bypass Cover Block-Off Plate for Gen III/IV LS Engines, Durable Aluminum Replacement for OE#12577903, 2 x 1/8" NPT Ports

#8

8. Subaru OEM Delete Fitting

• Weight: 2.39 oz
• Package Dimensions: 3.2 x 2.9 x 0.8 in

Best for: Genuine Subaru EJ fitting.

Why it ranks #8: This genuine Subaru fitting is specifically identified for EJ engines and WRX STI, but the listing provides fewer fitment details than the LS kits.

Genuine Subaru part number 15018AA090 identifies this oil-cooler delete fitting for EJ engines, including WRX and STI applications named in the title. Subaru states that the fitting came stock on vehicles without an oil cooler and is used to remove the cooler from the engine.

The OEM identity and part number provide a direct reference for buyers seeking the Subaru fitting rather than a universal plate. Its listed purpose is removing the oil cooler on Subaru EJ engines, and the description notes it came standard on vehicles not equipped with one. That original-equipment context helps frame the part’s role in a cooler-delete setup. The supplied information does not state additional hardware, sealing materials, or a broader fitment range beyond EJ engines and the WRX/STI title reference.

Skip it if you are building a GM LS engine; this is a Subaru EJ oil-cooler fitting, not an LS cover.

This fitting suits a Subaru EJ owner seeking the genuine component used on vehicles originally supplied without an oil cooler. The stated scope centers on EJ engines and WRX/STI, so it is not a universal delete fitting.

Listed on Amazon as: Subaru Oil Cooler Delete Fitting 15018AA090 EJ Engines WRX STI Genuine OEM

#9

9. SFriding Honda Delete Hose

• Weight: 16 oz

Best for: TRX450R post-failure cleanup.

Why it ranks #9: The delete hose is explicitly listed for the 2004–2005 Honda TRX450R and replaces specified cooler and hose OEM numbers.

For Honda TRX450R models from 2004–2005, this delete hose lets owners remove the oil cooler after a catastrophic engine failure, helping avoid debris left in the cooler reaching replacement engine parts. It also replaces three specified Honda cooler and hose references and is listed to reduce vehicle weight by about two pounds.

The listed TRX450R 2004–2005 fitment gives this hose a specific ATV application rather than broad cross-model coverage. Removing the oil cooler can help address debris remaining after catastrophic engine failure, a practical consideration when replacing engine parts. The product also replaces the specified cooler and two oil hose references, and its stated approximate two-pound weight reduction may matter to riders tracking vehicle weight. The listing describes a cleaner appearance and easier daily maintenance after cooler removal.

Skip it if you own a different ATV or TRX450R model year; this hose lists only 2004–2005 fitment.

This hose suits a TRX450R owner removing the cooler during post-failure engine work, especially when debris is a concern. Its listed application is limited to 2004–2005 models, so other years are outside the stated fitment.

Listed on Amazon as: Oil Cooler Delete Line Oil Hose for Honda TRX450R 2004-2005, 15600-HP1-003, 15510-HP1-000, 15520-HP1-000, Silver

#10

10. EMPI VW Cooler Bypass

• Weight: 11.04 oz

Best for: Volkswagen Type 1 oil routing.

Why it ranks #10: This part fits VW Type 1 engines but is described for using an external cooler or oil filter, not as a direct cooler-delete part.

Compatibility with Volkswagen Type 1 engines lets this EMPI bypass adapter support use of an external oil cooler or oil filter. Its stated airflow benefit is specific: the bypass eliminates airflow blockage to cylinders three and four, making it relevant to builders considering cooler or filter plumbing on a Type 1.

The adapter is listed for Volkswagen Type 1 engines and enables use of an external oil cooler or oil filter, tying its application to a specific engine family and plumbing setup. EMPI also states that it eliminates airflow blockage to cylinders three and four, a benefit relevant to engine cooling around those cylinders. The product title includes a gasket and hardware, but the available details do not identify their specifications, so installation planning should rely on the supplied kit contents rather than assumed dimensions.

Skip it if you are working on an LS or Subaru engine; this adapter is listed for Volkswagen Type 1 applications.

This adapter suits a Volkswagen Type 1 builder planning an external cooler or filter and considering airflow around cylinders three and four. The stated fitment is Type 1-specific, not a general-purpose oil-cooler delete.

Listed on Amazon as: Oil Cooler Bypass with Gasket & Hardware