Radium Engineering FPD-XR Direct Mount 3/8 NPT Fuel Pulse Damper Kit - Universal

• Universal

THIS IS A UNIVERSAL FITMENT PRODUCT, PLEASE ENSURE YOU HAVE VERIFIED FITMENT PRIOR TO PURCHASE.

The opening and closing of fuel injectors creates pressure pulses in the fuel rail which can lead to unstable fuel pressure. In order to achieve a safe and consistent rail pressure, a fuel pulse damper (FPD) is often necessary. The FPD's internal diaphragm will absorb oscillating pulses and stabilize fuel pressure. This correction can be measured throughout the RPM range and can often help idle surge, especially with high flow injectors. Furthermore, a fuel pulse damper can help solve erratic lean air/fuel ratio spikes, commonly experienced as "stumbling", that are difficult to tune out. 

What makes Radium FPDs unique?
Along with having the flexibilty of using common fittings, Radium Engineering FPD's use a vacuum/boost reference port which allows for proper fuel pulse damper performance even at elevated fuel pressures. This becomes essential for boosted systems that use a 1:1 rising rate fuel pressure regulator.

What is the difference between FPD-R and FPD-XR? 
The FPD-R (green top) is slightly shorter than the FPD-XR (black top) allowing it to be used in space-contrained applications.

 

WHICH DAMPER DO I CHOOSE?
The FPD-R (Fuel Pulse Damper-Range) and FPD-XR (Fuel Pulse Damper-Extra Range) both have unique base "static" fuel pressure requirements:
FPD-R base pressure requirement = 40 - 70psi (static)
FPD-XR base pressure requirement = 40 - 120psi (static)
Base pressure is the fuel pressure measured when the fuel pump is running WITHOUT a vacuum line connected to the regulator.

IMPORTANT: The ranges above are base static fuel pressures only. Any dynamic fuel pressure created by a rising-rate FPR outside of this range is acceptable, but only when the base "static" fuel pressure is set within these ranges and the vacuum/boost reference line is connected.

Example 1: 
Vehicle: Mitsubishi EVO
OEM Base Static Fuel Pressure: 43.5psi
Boost Pressure: 20psi
Rising Rate Pressure Regulator?: Yes
Notes: Even though fuel pressure is 63.5psi at full boost, either FPD-R or FPD-XR can work in this example because the base static pressure was set within the requirements. Vacuum/boost reference line must be hooked up to the FPD.

Example 2:
Vehicle: BMW E46 M3
OEM Base Static Fuel Pressure: 72.5psi
Boost Pressure: 20psi
Rising Rate Pressure Regulator?: Yes
Notes: Even though fuel pressure is 92.5psi at full boost, the FPD-XR will work in this example because the base static pressure was set within the requirements. The FPD-R cannot be used in this scenario. Vacuum/boost reference line must be hooked up to the FPD.

Features
The anodized aluminum housing features two selectable threaded male fittings. The 8AN ORB (3/4"-16 UNF threads) version seals using a Viton O-ring while the 3/8" NPT variation seals with the tapered pipe threads.


The FPDs can be mounted at any possible angle including upside down. For best results, the damper should be mounted directly onto the fuel rail(s). 

This product is safe for use with all fuel types including alcohol blends such as E85. Download the installation instructions for more info. 

Included

-Anodized and laser engraved aluminum top, R=range or XR=extra range
-Anodized aluminum body with male threads, 8AN ORB or 3/8" NPT
-Stainless steel hardware
-Rubber vacuum hose, 4mm ID
-Vacuum hose Y-fitting 
 

This item is non application specific. Please verify compatibility before purchase. May require some modification for proper installation.

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.

Limited Manufacturer Warranty*

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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