GrimmSpeed Head Gasket Set - EJ25 SAVCS STI / WRX / LGT 2004-2014 | 12400X

EAL the deal with a set of GrimmSpeed EJ25 Head Gaskets!

GrimmSpeed has set the standard for quality when it comes to aftermarket replacement gaskets so it’s only natural that we should offer our fans the MOST important gaskets their car will ever need: Introducing The GrimmSpeed EJ25 Head Gasket Sets! 

Feature-packed, these gaskets are a perfect fit for any engine build, from basic refresh to a high horsepower track monster. 

The GrimmSpeed Head Gaskets feature a multi-layer steel (MLS) construction, in which multiple grades are used to provide optimal surface and combustion chamber sealing as they are torqued down. The top and bottom layers feature a Nitrile Rubberized Coating that helps accommodate a rougher RA surface finish of up to 50microinch. This acts to better seal the non-critical areas of the gasket. In addition, the gasket edge includes a folded stopper layer that allows for optimal sealing for the combustion chamber. This is done to help reduce the chances of combustion gasses causing head gasket failures under extremely high cylinder pressures that built engines can experience.

After talking to numerous engine builders/tuners it was clear that creating a variety of gasket thicknesses was key for pairing them with the right build. With that in mind, we’ve made the gaskets available in multiple thicknesses (.78, 1.1, 1.5mm) to help fine tune each individual build. In addition, the slightly oversized bore diameters will allow for up to 0.5mm overbore.

The EJ specific gaskets include enlarged center head bolt holes to accommodate up to a 13mm head studs. This is a popular upgrade option for many higher power builds, where additional cylinder head clamping force is needed.

We’ve outdone ourselves this time, The GrimmSpeed Head Gaskets carry on the legacy of quality that you’ve come to know from our other extremely popular gaskets.

Quick Specs

• Sold as a Set/Pair - Single and Dual AVCS fitment
• Die Cut Multi-Layer [Stainless] Steel (MLS) Construction - Provides smooth edge finish and consistency from batch to batch, ±0.001” manufacturing tolerance
• Folded Stopper Layer to Better Seal the Combustion Chamber
• .25micron Nitrile Rubber Layer Coating - Reduces chances of leaking on imperfectly smooth mating surfaces over non-coated gasket. 
• Accommodates up to 100.0mm bore
• Compatible with up to 13mm, ½” studs
• 0.78mm, 1.1mm and 1.5mm thickness (after crushing)

Testing

GrimmSpeed High Performance Head Gaskets are designed to optimize combustion chamber sealing. This is done by using a unique gasket design feature which sets us apart from the competition. By strategically undercutting the middle layer of the gasket near the combustion chamber, we can control the crushing of outer layers, which in turn creates a perfect seal around the combustion chamber.  

We can visually demonstrate this feature by using pressure sensitive film and compressing the gasket in a manner which mimics the tightening of a head against the block. The film changes colors from white to pink to red as pressure is applied to denote areas of high and low pressure application. This information will then allow for easy visual verification of effectiveness in sealing of a gasket against a surface.

As seen in the results, the combustion chambers are sealed evenly and equally around the circumference of the cylinder by the deep part circles. This visual representation is showing that combustion gasses are going to be held in the chamber and directed towards pushing the piston instead of escaping. Failure of a gasket to seal with even pressure around the circumference of the cylinder would be detrimental for performance and reliability of a gasket and would most certainly result in failure.  

When combining the perfect sealing, nitrile coating and other features of the gaskets, we are able to ensure that your engine build is ready for anything that you throw at it. From basic engine refreshes to full blown race builds, The Mark of Innovation from GrimmSpeed keeps you in control under pressure!

Fitments

• 04-07 STI [EJ25 SAVCS]
• 06-14 WRX [EJ25 SAVCS]
• 04-08 FXT [EJ25 SAVCS]
• 05-09 LGT [EJ25 SAVCS]
• 08-20 STI [EJ25B DAVCS]

At JDMuscle, we understand that fast and reliable shipping is crucial. With multiple distribution centers across the nation, most in-stock items are shipped within 1-2 business days. On average, you can expect delivery within 1-5 business days for in-stock items. Please note, however, that some products may ship directly from vendors, which could result in additional delays. Products sourced from overseas may also take longer to arrive.

Free Shipping over $199 Policy

• Free shipping is available only for the 48 contiguous states in the U.S.
• Ground shipping applies to regular-sized items only.
• Oversized items such as lips, hoods, and trunks requiring freight shipping are not included in the free shipping program.
• Some manufacturers may impose a shipping surcharge, which will be excluded from the free shipping program.
• The most accurate shipping costs will be displayed at checkout. If you believe the shipping cost is incorrect, please contact us at sales@jdmuscleusa.com for further review.

Carriers

We ship via FedEx, UPS, USPS, and DHL. While we strive to use the most efficient option, we cannot guarantee which carrier will deliver your order. Your items may arrive in multiple packages through different carriers.

Processing Time and Shipping Cut-off

Orders typically take 24 hours to process, with shipping cut-off at 3:00 PM EST. Transit times vary based on location and carrier. Some items, especially those requiring freight shipping, may have extended processing and delivery times. For freight shipping inquiries, contact us at sales@jdmuscleusa.com.

International and Special Shipping Considerations

• International orders are subject to higher shipping fees. If you would like to review your shipping cost, email us at sales@jdmuscleusa.com with your full address and items you plan to purchase.
• In some cases, shipping costs may be incorrectly calculated for international or oversized items. We reserve the right to adjust the shipping fee and will work with you to negotiate a fair cost if needed.
• Customers can challenge and request a review of international shipping fees, and we’ll do our best to find a lower rate where possible.
• Customs Fees & Import Taxes: The shipping charge you pay does not include customs fees or import taxes. These charges vary by country and are the customer’s responsibility. Please check with your local customs office for more details before placing an order.
• Shipping Cost Adjustments: Shipping rates fluctuate, and while we strive to provide the most competitive rates, there may be instances where the shipping cost you paid is significantly lower than the actual cost. In such cases, we reserve the right to request the difference to ensure we cover our basic expenses. We appreciate your understanding and will always aim to keep shipping costs as affordable as possible.

Address Modifications and Fees

• Any modifications to a shipping address after an order is placed may be subject to additional fees.
• For single, small packages, the flat fee is $20. For larger or multiple packages, the fee may be up to $60 or more.

Freight Shipping Guidelines

• Freight shipments require you to be present at the time of delivery.
• The delivery driver may provide a delivery receipt (Bill of Lading). It is crucial to inspect the shipment before signing.
• Carefully check the packaging for any visible damage (dents, punctures, rips) and notate it on the Bill of Lading.
• Open the package and inspect the product itself. If damage is found, document it in detail on the Bill of Lading, take photos, and contact the shipping company to initiate a damage claim.
• Do not refuse the shipment. Contact us at sales@jdmuscleusa.com for guidance.
• If the delivery driver is unable to wait for inspection, note this on the Bill of Lading.

Failure to document damages before signing the Bill of Lading will void any claims for refunds or replacements.

Pre-Installation Inspection Policy

We strongly recommend inspecting all parts or items upon arrival before installation. If you identify any damage, imperfections or missing components, report them immediately to sales@jdmuscleusa.com. Do not install the item. Please note that reports of damage, defects, imperfections or missing components after installation will NOT be honored.

Package Protection

We do our best to ensure your items arrive to you safely but sometimes things happen. If you utilized our Checkout+ feature, rest assured that your package is protected! With package protection, in the event that your package is lost, stolen, or damaged while in transit, we will replace it free of charge. To start a shipping claim, please click here.

Need Assistance?

If you have any concerns about shipping costs or transit times, or if you notice discrepancies during checkout, feel free to reach out to us at sales@jdmuscleusa.com. We’re happy to assist you and ensure a smooth delivery experience.

Our policy lasts 30 days. If 30 days have passed since your purchase, unfortunately, we can’t offer you a refund or exchange. To initiate a return, please email us at sales@jdmuscleusa.com.

Eligibility for Returns

✅ Items must be unused and in the same condition as when received.
✅ Items must be in their original packaging.

Non-Returnable Items

❌ Gift cards
❌ Special-order or custom products

How to Initiate a Return

📧 Include the following details in your return request email:

Order Number

Item(s) to be returned

Reason for return

Important Notes:

Do NOT send your purchase back to the manufacturer.

Do NOT return any items without first setting up a return request with us.

Partial Refunds

Partial refunds may be granted under the following conditions:

⚠️ Items not in original condition, damaged, or missing parts not due to our error.
⚠️ Items returned more than 30 days after delivery.

Restocking Fees

Some manufacturers may charge a restocking fee, which includes but not limited to:

ManufacturerRestocking Fee

ESR30%

JDMuscle15%

PLM & Option Lab 20%

Cancellations

Before placing an order, please confirm availability.

Cancellations within 7 days may be subject to fees to cover third-party transaction costs.

Once the order has been processed (packaged or tracking generated), cancellations are not allowed. Eligible items may be returned instead.

Special-order items cannot be canceled.

Refund Process

🔄 Once your return is received and inspected, we will notify you of the refund status.
💳 Approved refunds will be credited back to your original payment method within 3-10 business days (depending on the payment provider).

Late or Missing Refunds

🔍 Check your bank statement — sometimes the refund may not appear as a new entry but as the disappearance of the pending charge. 📞 Contact your credit card or financing company — they may require additional time for processing.

If you’ve done all of the above and still haven’t received your refund, email us at sales@jdmuscleusa.com for assistance.

Sale Items

Only full-priced items are eligible for returns and refunds.

Exchanges

We replace items only if they are defective or damaged. To request an exchange for the same item, email us at sales@jdmuscleusa.com.

Gifts

🎁 If the item was marked as a gift when purchased and shipped directly to you, you will receive a gift credit for the return value.
📩 If the gift giver had the item shipped to themselves, we will refund the gift giver.

Return Shipping

📦 Customers are responsible for return shipping costs unless the item is damaged, defective, or incorrect (in which case we will cover shipping both ways).

Initial shipping costs are non-refundable.

Return shipping costs will be deducted from the refund amount.

For items over $75, consider using a trackable shipping service or purchasing shipping insurance. We are not responsible for lost or damaged items during return shipping.

Return Shipping Address: Please use the address provided in the RMA/return instructions, as it may differ from the initial shipping address.

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