Edelbrock PRO-FLO XT 3527 User manual

1
Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
TABLE OF CONTENTS
Part #3527 and #3528
Introduction.................................................................................................................................................1
Components................................................................................................................................................2
Preliminaries...............................................................................................................................................3
Fuel System................................................................................................................................................6
Induction System ......................................................................................................................................10
Sensors ....................................................................................................................................................13
O2 Sensor Installation ...............................................................................................................................15
Main System Harness ...............................................................................................................................16
Ignition System .........................................................................................................................................25
Other Applications.................................................................................................................................... 26
Software Installation .................................................................................................................................28
Calibration Selection .................................................................................................................................29
System Start-Up........................................................................................................................................30
Electronic Engine Management .................................................................................................................33
Pro-Flo Quick Tuning Guide.......................................................................................................................34
Calibration Module Flowchart....................................................................................................................36
Parts and Part Numbers ............................................................................................................................37
Service & Warranty ...................................................................................................................................39
INTRODUCTION
Thank you for selecting the Edelbrock Pro-Flo XT Fuel Injection System. This Multi-Point Fuel Injection System has been designed for 350 c.i.d.
small-block Chevrolet engines, and is designed to provide excellent performance, fuel economy, and maintenance-free operation. Installation of
the Edelbrock Pro-Flo XT Fuel Injection System involves modifications to the fuel system, ignition system, induction system, and possibly the
valve train. Although there are steps that must take place before others, the modifications do not necessarily have to be performed in a particular
order. Each modification is described in a separate section in this manual. Please study these instructions carefully before beginning installation
of any part of the Pro-Flo XT system.
If you have any questions, do not hesitate to call our
EFI Technical Hotline at [phone], 7am-5pm PST, Monday-Friday
E-mail: [email protected]

2
Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
PRIMARY KIT COMPONENTS
❑Electronic Control Unit/System ECU ❑Fuel filter
❑Calibration Module ❑Fuel rail assembly
❑Distributor conversion kit ❑Fuel pressure regulator
❑Fuel injectors ❑High pressure fuel pump
❑ECU power relay/Fuel pump relay ❑Intake manifold
❑Manifold Absolute Pressure (MAP) Sensor ❑Four barrel air valve
❑Manifold Air Temperature (MAT) Sensor ❑Idle Air Control (IAC) solenoid, integrated with air valve
❑Coolant Temperature Sensor (CTS) ❑Main system harness
❑Throttle Position Sensor (TPS), integrated with air valve ❑Fuel pump harness
❑Oxygen (O2) sensor ❑Installation package
❑USB/Serial Converter ❑Ignition Harness
❑Software CD ❑MSD Blaster Coil
❑Mallory Distributor
Many Pro-Flo XT components, including the Manifold Absolute Pressure sensor, fuel pressure regulator, Coolant Temperature sensor, and the fuel
filter are standard OEM pieces. In the event that one of these parts needs to be replaced, you are likely to find a replacement at your local parts
supplier, in addition to your local Edelbrock dealer or directly from Edelbrock. For a list of part numbers, refer to the PART NUMBERS section at
the back of this manual.

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Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
TOOLS AND EQUIPMENT
Use the following checklist for items needed.
❑Box and open end wrenches
❑Socket set
❑Distributor wrench
❑Pliers (channel locks and hose clamp)
❑Screwdrivers (regular and Phillips)
❑Torque wrench
❑Hammer
❑Gasket scraper or putty knife
❑Timing light
❑Vacuum gauge
❑Rags
❑Water bucket
❑Drill and bits
❑Hole saw (1 1/4-inch or 1 3/4-inch)
❑Tubing wrenches
❑Tubing cutter
PRELIMINARY CHECKLIST
1. CAREFULLY STUDY AND UNDERSTAND ALL INSTRUCTIONS, BEFORE BEGINNING THIS INSTALLATION.
NOTE: This installation can be accomplished using common tools and procedures. However, you should have a basic
knowledge of automotive repair and modification and be familiar with and comfortable working on your vehicle. If you do
not feel comfortable working on your vehicle, it is recommended to have the installation completed by a professional
mechanic.
2. Examine the Pro-Flo XT system for possible shipping damage. If damaged, contact your dealer immediately.
3. The 3527 & 3528 kits are designed for use with a standard Small Block Chevy V8 firing order.
4. Check all threaded manifold holes.
5. Check all internal manifold passages with a light and wire, making sure they are clean and unobstructed.
6. Check automatic transmission shift points before removal of your stock manifold and adjust linkage after Edelbrock
manifold installation for same shift points (if needed).
NOTE::We recommend that you refer to this checklist again after installation to be sure that you have completed all steps.
HARDWARE AND PARTS RECOMMENDED
Use the following checklist for items needed.
❑Intake gasket; #3527 kits use Edelbrock gaskets #7201; #3528
kits use gaskets #7235
❑Pipe plugs, if needed
❑5/16-inch steel tubing (approximate equal length to fuel pickup
line in tank)
❑Edelbrock Gasgacinch #9300
❑Loctite 598 OEM High Temperature Silicone Gasket (O2Sensor
Compatible)
❑Radiator coolant
❑Wiring diagram for your vehicle
❑Teflon tape or liquid Teflon thread sealer
❑Manifold bolt kit; #3527use #8504; #3528 uses #8516
❑195° Thermostat
❑Resistor type spark plugs (Use correct heat range for your
particular application
❑Set of low-resistance spark plug wires with high EMI suppression
(DO NOT use solid core spark plug wires)
❑Dynojet wideband commander (Optional, not included)
❑DB9 Serial cable (Optional, not included)
❑Late model low profile water neck such as Trans-Dapt #9229 or
GM #12342034 (chrome)

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Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
MANIFOLD & CARBURETOR HEIGHT VS.
PRO-FLO XT HEIGHT
1. Lay a straightedge (such as a yardstick) across the top of the air
cleaner from front to back.
2. Measure from block and manifold end seal surfaces to
straightedge.
3. Record these measurements (height A and height B).
4. Add height A and height B and divide by two to get the average
height.
5. The Pro-Flo XT manifold is 9” tall at the center and 9.125” at the
throttle body flange.
6. Compare this to your original measurements. If the Pro-Flo XT unit
is taller, subtract this amount from the hood clearance figure to
determine new hood clearance.
CAUTION: You must maintain at least 1/2-inch clearance between the
hood and manifold because of engine torque. If you have insufficient
clearance, a hood scoop may solve the problem.
EMISSION CONTROLS
The Edelbrock Pro-Flo XT system will not accept stock emissions
control systems. Check local laws for requirements before installing
the Pro-Flo system. Not legal on pollution-controlled motor vehicles.
DETERMINING HOOD CLEARANCE
NOTE: Check hood clearance before removing stock manifold.
1. Use modeling clay or putty to make five small cones, two or three
inches high.
2. Position cones on air cleaner at front, rear, each side, and on
center stud.
3. Close hood to locked position and re-open.
4. The height of the cones indicate the amount of clearance
between the hood and the air cleaner. Record these
measurements.

5
Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
FUEL REQUIREMENTS
Because the Pro-Flo XT system uses an Oxygen sensor, you must use unleaded fuel only. Leaded fuels will damage the O2sensor. If you do use
leaded fuel in your vehicle, do not install the O2sensor and do not operate the vehicle in the closed loop fuel mode.
AUTOMATIC TRANSMISSION CHECK
For best performance, economy, and emissions, the shift point must be checked before and after the manifold change.
NOTE: This check should be performed ONLY at a sanctioned drag strip or test track.
With the shifter in Drive, accelerate to wide open throttle from a standing start. Hold in this position, noting speedometer MPH when the
transmission makes the first 1-2 shift. After the Pro-Flo XT system has been installed, make the same test, again noting MPH of this first shift.
The transmissions in certain vehicles require precise adjustments. We recommend that you consult a reputable transmission shop for final
adjustments once the Pro-Flo system has been installed. Incorrect shift points can result in transmission damage.
ENGINE CLEANING
Edelbrock recommends that the Pro-Flo XT system be installed on a clean engine in order to prevent dirt from falling into the engine lifter valley
or intake ports.
1. Cover ignition. Use engine degreaser and a brush to thoroughly clean the manifold and the area between the manifold and valve covers.
2. Rinse with water and blow dry.
EXHAUST MANIFOLD HEAT RISER VALVE
If your vehicle is equipped with an exhaust manifold heat riser valve (typically located on the passenger side of the vehicle below the exhaust
manifold), remove the valve for proper operation. If applicable, any air injection tubes must be removed and holes in the exhaust manifold
plugged for proper operation.
HEADERS
For best performance, headers are recommended. For this application, header primary tube diameter should be 1-3/4 inch, approximately 31
inches long and terminating into a 3 inch collector. The remainder of the exhaust system should consist of dual exhaust and tail pipes, at least 2-
1/4 inches in diameter with low back pressure mufflers.
COOLING SYSTEM
The minimum requirements for the thermostat are 180° but the ideal thermostat is 195°. When the vehicle is at 175 or below, system will stay
in cold start mode and not perform properly.

6
Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
FUEL SYSTEM
Because your Edelbrock Pro-Flo XT system controls fuel delivery very differently than a carburetor, some conversions to your fuel system are
necessary. Pro-Flo XT electronic fuel injection requires high and constant fuel volume and fuel pressure. For this reason, a good primary fuel
line is critical. The Pro-Flo XT system includes a 3/8-inch high pressure fuel line which must be used as the primary fuel line. The fuel that
bypasses the injectors must be returned to the fuel tank via a return fuel line. If your vehicle is already equipped with a fuel pump bypass line,
this line can be used as the return fuel line. If not, the original primary line may be used as the return line. If desired, a 15 foot length of 3/8” ID
Pro Classic hose is supplied for use as the return line.
Many late-model cars are equipped with an additional fuel line which runs to a charcoal canister mounted on the driver side of the vehicle. This
line MUST be re-installed after the fuel system conversion and MUST NOT be used as the return fuel line.
Tank Side
Engine Side
FUEL PUMP AND FILTER
The Pro-Flo XT system uses a single Edelbrock high-pressure electric fuel pump which is
capable of pumping 50 psi. The pump relay will shut down the pump if it does not receive an
engine-run signal from the ECU, as in the case of a stall. This safety precaution is necessary
when using a high-pressure fuel line. The provided fuel filter should be mounted between the
engine compartment and the fuel pump to allow fuel to be pushed through the filter rather
than drawn through. Electrical connectors should face the front of vehicle. Make sure the
fuel pump is mounted at or below the bottom of your fuel tank. If the pump is mounted above
this point, fuel pump failure will occur.
FUEL PRESSURE REGULATOR AND FUEL SUPPLY LINE
Fuel pressure is as important as fuel volume, particularly in fuel injection. The Pro-Flo XT fuel pressure regulator maintains a constant pressure at
the injectors with a spring loaded by-pass to the return fuel line. Manifold Absolute Pressure references the regulator diaphragm to maintain
constant pressure across all 8 injectors, regardless of fluctuating manifold pressure (vacuum) level. The fuel that is not injected is returned to the
fuel tank via the return fuel line.
RETURN FUEL LINE
Due to the high fuel pressure used by the Pro-Flo system, the supplied 3/8-inch Pro Classic high pressure fuel line MUST be used as the
primary fuel line, and a bypass fuel return line must be installed. There are three options for installing a bypass return line.
1. Use the 3/8” Pro Classic rubber fuel line provided with the system as the fuel return line.
2. Use the vehicle’s existing primary line as the fuel return line with modification to the pick up as described below.
3. Use the vehicle’s existing return line (if so equipped) as the fuel return line. This option applies only to vehicles previously equipped with fuel
injection. If the vehicle is not already equipped with a return line, some fuel tank modifications are required for routing the return line
through the sending unit plate back into the tank. The first two methods listed below require some welding and should be done by a
professional radiator or fuel system repair shop.
Return Side Supply Side

RUBBER RETURN LINE METHOD
Drill a 5/16-inch hole in the sending unit plate adjacent to where the main line enters the tank. This will be the hole for your return line. Insert a
short length of 5/16-inch hard line (available at most radiator shops) into the hole and weld it to the sending unit plate. The hard line should
extend through the hole 1 to 2 inches on each side of the plate. Connect a length (at least 4 inches) of 5/16-inch rubber return line hose to the
hard line that will extend into the tank. Connect the rubber line to the fuel pickup line using tie wraps.
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Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
BULKHEAD FITTING METHOD
Drill a 9/16-inch hole in the sending unit plate adjacent to where the main line enters the tank. This will be the hole for your return line. Insert a
#6 AN bulkhead fitting (available at most radiator shops) into the hole, the narrow end of the fitting on the inside of the plate. Apply a rubber
washer or RTV sealant and fasten the fitting to the plate with the nut. Connect a length (at least 4 inches) of flexible return line (rubber or
braided hose) to the fitting end. Connect the return line to the fuel pickup line using tie wraps.
NOTE: THIS METHOD REQUIRES NO WELDING OF THE FUEL SYSTEM.
NOTE: Whichever method you use to install the return fuel line, be
careful to keep the end of the line away from the fuel pickup, as
shown. Otherwise, aerated return fuel can be drawn into the pickup.

HARD RETURN LINE METHOD
Drill a 5/16-inch hole in the sending unit plate adjacent to where the main line, enters the tank. This will be the hole for your return line. Insert a
length of 5/16-inch hard line (available at most radiator shops) into the hole and weld it to the sending unit plate. The hard line should extend
through the hole 1 to 2 inches on the outside of the plate. On the inside of the plate, the hard line should follow the contours of the fuel pickup
line. Bend the end of the return line away from the sock on the end of the fuel pickup line. Solder or weld the return hard line to the fuel pickup
line.
8
Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
BULKHEAD FITTING METHOD
HARD RETURN LINE METHOD

9
Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
NOTE: ALL WELDING AND SOLDERING OF THE FUEL SYSTEM MUST BE PERFORMED BY A
PROFESSIONAL RADIATOR AND/OR FUEL SYSTEM REPAIR SHOP.
FUEL SYSTEM INSTALLATION
1. Drain the fuel tank.
2. Remove all fuel lines from the tank and from the carburetor.
3. Remove the fuel tank.
NOTE: While the fuel tank is removed from the car, it is recommended that it be professionally
cleaned in order to remove any rust or dirt that may have accumulated inside and which could
damage the injectors.
4. Remove the sending unit from the fuel tank. Refer to the RETURN FUEL LINE methods above for
installing the bypass fuel return line.
5. Install the provided 3/8-inch primary fuel line directly above the original line, which may
now serve as a return line. Use large radius bends. Avoid the exhaust pipe and any
sharp edges.
NOTE: The 3/8” Pro Classic high pressure fuel line supplied with the Pro-Flo system
must be used as the primary fuel line. See the following section for assembly
instructions.
6. If you do not use the original fuel as the return line, route the return line directly
alongside the provided 3/8-inch primary fuel line.
7. Mount the fuel pump between the tank and the fuel filter as low and as close to the
fuel tank as possible. The pump is directional. Electrical connectors should face the
front of vehicle. The fuel pump needs to be at or below the bottom of the fuel tank.
8. Mount the fuel filter between the fuel pump and the engine.
9. Re-install the modified sending unit plate to the clean fuel tank.
10. Reinstall the fuel tank.
11. Attach the primary line and return line to the sending unit plate on the tank.
12. Re-attach all other fuel lines at the tank (vapor purge lines, etc., if so equipped).
13. Secure the primary and return fuel lines with the provided tie-wraps, or with Adel clamps if
available.
14. Re-attach all fuel lines to the induction system once it has been installed.
15. Use the 10-foot wiring harness to connect the fuel pump to the Main System Harness. Route the
harness away from the exhaust pipe and any sharp edges. This harness may be cut to length.
Replacement terminals are provided with the Pro-Flo XT system. Cover the connection to the
positive terminal with the sleeve and tie wrap provided. Refer to the MAIN SYSTEM HARNESS section of this manual for details.
16. Before starting the engine, turn the ignition key to the ON position 4 or 5 times to prime the electric fuel pump, fuel lines, and fuel rails. You
should hear the pump run for approximately 2 seconds each time. Check the entire fuel system for leaks. Refer to the SYSTEM START-UP
section of this manual for details.

10
Pro-Flo EFI Installation Instructions
©2008 Edelbrock Corporation
Brochure No. 63-3527
Catalog #3527, #3528
Rev. 8/08 - AJ/mc
INDUCTION SYSTEM
The Edelbrock Pro-Flo XT system delivers fuel and air to the engine via the induction system consisting primarily of a manifold, 90mm air valve,
fuel rails, and fuel injectors. The induction system is fully assembled, tested, seal checked, and flowed at the factory and is as easy to install as a
manifold. DO NOT DISASSEMBLE any of these components during installation.
INTAKE MANIFOLD
The new Edelbrock Pro-Flo XT manifold has been designed specifically
for electronic fuel injection applications.
90mm THROTTLE BODY
The Pro-Flo XT system uses a throttle body with 90mm air valve. The
air valve can flow up to 1000 cfm at 1.5" of mercury when wide open.
FUEL INJECTORS
The Pro-Flo XT #3527 & #3528
systems use high impedance pintle-
type fuel injectors. The injectors
are capable of flowing 29 lbs./hr. at
50 psi. The injectors mount directly
onto the manifold, one at each port,
for fuel delivery that is precisely
controlled and instantaneously
injected.
FUEL RAILS
The extruded aluminum rail assembly routes the high pressure fuel to
the injectors. Aluminum rails have an advantage over soft rails both in
terms of style and safety.
ASSEMBLING PRO-CLASSIC HOSE
Step One: Cut hose to length,
as straight and square as
possible, with razor blade-type
hose cutter or shears.
Step Two: Unscrew socket
from hose end. Push hose into
socket, turning counter-
clockwise, until hose is seated
against step in socket. Make
sure rubber part of hose does not
protrude into socket threads.
Step Three: Apply Russell
assembly lube to threads on
nipple assembly and in socket.
Insert nipple into socket/hose
and start threads by hand
(clockwise).
Step Four: Hold socket/hose in
vise. Turn nipple with wrench
until there is less than 1/16"
between nipple hex and socket.
Repeat Steps 1-3 for other end of
hose. Then, flush hose assembly
with solvent or soapy water and
blow clean with compressed air or
let air dry.