Fuel Injector Modification

Are your current fuel injectors meeting your horsepower needs? Perhaps you inadvertently purchased a set of fuel injectors that were meant to fit another vehicle? Have you changed cars but kept your trusty injectors?

Fuel Injector Clinic can offer solutions to many fit and flow modification issues!

Since there are so many different injectors available both OEM and aftermarket, the best way to determine if we can modify the injectors you have is to take a few pictures and email them to us (Service@fuelinjectorclinic.com), then call to discuss the possibility of modification.

Our modification services are listed below:


Once we have determined that your fuel injectors are eligible for flow modification we will flow test and modify them to the desired flow rate*. Once the modifications are complete we will replace any standard injector seals and you will receive a flow data sheet outlining the new flow rates of your injectors. 

*Flow modification requests should be discussed with a technician PRIOR to shipment to Fuel Injector Clinic. We request this in order to ensure that the desired flow rate is attainable and so that we can advise the customer of any potential issues.


Many injectors both OEM and aftermarket can be adapted to fit other vehicles. Fit modification may involve the removal of material from the injector or sealing surface, or could require the addition of spacers, cushions, extenders, and/or seal retainers in order to fit properly*. The cost for fit modification is $20.00 and includes any standard injector seals.

*Fuel Injector Clinic cannot modify the electrical connector on an injector. The connectors are molded into the injector during manufacture and cannot be changed. If you need to resolve a plug difference, please refer to our 'More Products - Plugs / Adapters / Pigtails' page for the correct plug and play adaptor.

MAILING INSTRUCTIONS: Simply print our service form and fill it out, then put it in a package* with your clean, dry, carefully packed fuel injectors (they should be packaged so that they don’t bang into each other.) Once we receive your injectors we will begin the flow testing and/or cleaning process.           

*In order to reduce turnaround time, Fuel Injector Clinic suggests USPS Priority Mail flat rate as the fastest most cost effective shipping method. Don’t forget the insurance!

RETURN SHIPPING: Fuel Injector Clinic uses USPS Priority Mail service with insurance and tracking unless otherwise requested. All return shipping charges are the responsibility of the customer. Typical return cost for a set of four injectors via USPS Priority Mail to an address in the US with $300 insurance is between $8 and $12. We will E-mail you your tracking information to you if you have included an E-mail address on the service form.

* Policy on unclaimed items: Please note that unclaimed items will be held for a maximum period of 3 months from the date of receipt. After this period, we reserve the right to dispose of the items. To avoid any inconvenience, we encourage customers to claim their items promptly. Additionally, it is important to be aware that we do not cover replacements for items that remain unclaimed beyond the 3-month period. We appreciate your understanding and cooperation in adhering to these policies.