Edelbrock 7137, 7138, 3629, 3644, 3657 Installation Instructions Manual

©2009 Edelbrock Corporation

Brochure #63-3627

Part #3627, 3629, 3644, 3657
Rev. 8/09 - AJ/mc

ALUMINUM FUEL RAIL KIT

For Use with Pro-Flo XT Intake Manifolds

Part #3627, 3629, 3644, 3657

INSTALLATION INSTRUCTIONS

PLEASE study these instructions carefully before beginning this installation. Most installations can be accomplished with common

tools and procedures. However, you should be familiar with and comfortable working on your vehicle. If you do not feel comfortable
performing this installation, it is recommended to have the installation completed by a mechanic. If you have any questions, please
call our Technical Hotline at: 1-800-416-8628, 7:00 am - 5:00 pm, Pacific Standard Time.

• DESCRIPTION: These Aluminum Fuel Rail Kits are designed to be used with the Edelbrock Pro-Flo XT intake manifolds, see the
table below for specific applications. They are intended to be used with compact injectors that have a 1.50” o-ring to o-ring
length, such as our high impedance Edelbrock Pico injectors, or standard height injectors with a 2.50” o-ring to o-ring spacing
such as our Edelbrock MotoTron injectors when used with the supplied adapters. See our catalog under

“EFI Replacement Parts”

for details. NOTE: Fuel Rail Kit #3629 may require modification to the brackets to clear large body aftermarket injectors.

Kit includes the following:

❑

2 - Machined Fuel Rail Extrusions (ends tapped for 3/8" pipe)

❑

4 - Fuel Rail Brackets

❑

4 - ¼”-20 x 1-¼” Socket Head Capscrew

❑

4 - ¼”-20 Nyloc Hex Nut

❑

8 - ¼” AN Washer

❑

4 - ¼” Lock Washer

❑

8 - ¼”-20 x 5/8” Socket Button Head Capscrew

❑

4 - ¼”-20 x 1-1/2” Hex Head Bolt

• FUEL RAIL KIT: Install fuel rail kit and your injectors using the included 1/4”-20 nuts and bolts. Apply an o-ring assembly lube
to the injector o-rings before installing them into the manifold and fuel rails. Brake system assembly lube works well. Make sure
that the o-rings of the injectors create a complete seal with the fuel rail and the intake manifold to prevent any air or fuel leaks.
Most applications will require a fuel pressure regulator and crossover, which are not included with this kit.

• INSTALLATION: Use 1-1/4” long socket head capscrews to mount the fuel rails directly to the raised bosses located on the
runners only when using Pico style injectors. For standard height injector applications, attach the four brackets using the supplied
button head screws. Do not use washers underneath the button head screws as this will limit thread engagement. The brackets
have a slight compound bend in them to compensate for the thickness of the material. Orient the brackets so that the top portion
is closer to the plenum than the bottom. This will keep the rails aligned with the injector provisions of the manifold. Then use
the longer hex head bolts, washers and locknuts to mount the fuel rails to the brackets.

• FINAL CHECKS: After finishing assembly, check the following:

❑ Check the fit of each injector. They should be able to rotate freely. The O-rings should be fully inside their respective bores.
❑ Activate the fuel pump and fully check the system for any leaks prior to starting the engine.

Edelbrock Corporation • 2700 California St. • Torrance, CA 90503

Tech-Line: 800-416-8628

IMPORTANT NOTE:

Proper installation is the responsibility of the installer. Improper installation will void warranty and may result in

poor performance and engine or vehicle damage.

Application

Fuel Rail Kit

Part Number

Pro-Flo XT Intake Manifold

Part Number

Small Block Chevy 3627

7127 / 7128

(‘55-’86 Cyl. Heads / Vortec)

Chevy Gen III/IV

(LS1, LS2, etc.) *

3629 7139

Big Block Chevy 3657 7135

Big Block Chrysler 3644 7144

*Does not include engines equipped with L92 heads.

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