Installation Guide

Read it all.. everything is important.

Red is a safety/danger warning

Blue is for really important that will save you time if followed

Italicized is for description 

Use of generators is discouraged as the alternator provides cleaner, less noise, and steadier power for the EFI system.  If you plan to use a generator, it is highly recommended to install a power conditioner (capacitor box) inline to minimize the power spikes.  One wire alternators (Converted LM) are easily obtainable and at swap meets and other Corvair members/vendors. Early model swaps will require a new Delcotron and Alternator.  On late models (1965-1960) cars, the ECM/Relay panel is designed to be mounted at the old external regulator location.  Remember to add a diode on the gauge side of the alternator to prevent  a”running-on” condition due to feedback through the bulb (Details below). 

The Corvair EFI installation is simple if taken in small areas and verify each operation as you install.

Installation Steps
Disconnect battery power (Neg cable)
Remove Carb System
Modify Fuel Sending Unit to Accept Internal pump
Drill Hole for Return Line
Install Fuel Pressure Regulator (FPR)
Install Fuel Return Line (FPR to Filler Tube)
Install Timing wheel
Install exhaust bung
Install Injection Fuel Lines
Remove Choke rod on passenger side head
Mount Control Panel w/ECM on the drivers side firewall.
Install wiring harness over engine.
Install ETS (Engine Temp Sensor)
Install Carb Spacer and Gaskets
Install TBIs
Install Ignition Coil Pack/Distributor
Install Crank Sensor Bracket
Install Crank Sensor (Adjust .30 to .60)
Connect Crank Sensor wire
Install Main Ground wires and DIS ground cables
Connect all sensors.
Connect the large ground terminal at the left rear of engine compartment.
Connect a 14 gauge (Red) wire from the harness to your electric fuel pump.
Connect the 14 gauge (Red) wire to a full-time fused 12 Volt Battery
Connect the 16 gauge (orange) wire to the 12V Switch (12V when key is on)
(Optional) WBO2, Idle Air Control Valve
Check with Tuner Studio.
Check for Leaks
Check for Leaks
Test start and establish stable idle
Log test drive and make notes

Safety:  Have a fire extinguisher or other items handy for your safety when working with fuel. Gasoline is very flammable and can get out of hand very quickly.  Minimize the use of rubber hose as it does not resist fire or abrasion.  If you are not comfortable doing your fuel line work, you may want to find someone more experienced to help.  You may lose your car or even your life…. so think about safety in all aspects of installation, testing, repair and driving.

Remove Carb System:  Before removing your system, make sure that your engine is pointed to #1 plug wire position.  This will aid in the installation and ensure a quick and easy start after installation.  You must remove the Carbs, Fuel Lines, round fuel pump and fuel pump rod. (take the Linkage off also and lay aside as you will reuse these items).  Do not remove the inside Carb stud as it needs no adjustment.  The outside stud will need 1/2″ removed from the bottom (course threads) to in sure proper fit of the throttle body.  

Fuel System:

Tank Condition:  You must first ask yourself….. and be honest about the condition of your tank.  If your tank has rust and garbage, these items will go through the pump and destroy it…. period.  If your tank is not in good shape or is suspect, remove tank, have it cleaned or install a new one.  Corvair tanks are over 50 years old and most have rust and is recommended that tank is removed and cleaned.  This will put your Corvair on the side of the road and one of the last things you want to scrimp on.  The 68/69 and Turbos have a return line already built in, but is very restrictive due to its small size.  

Fuel Pumps:  Before you start, You must decide which method of fuel delivery is right for you.  They are 3 fuel system methods:

  1.  Fuel Pump in Tank: (most difficult, but quiet and low failure rate)
  2.  External High Pressure pump: (Pump under passenger floor) Noisier than all others
  3.  External 2 Pumps:  One (1) low pressure pump under passenger floor and One (1) high pressure pump behind firewall area (above differential/starter area).  This allows the repair or replacement of pumps without removing tank and also has a filter between the low and high pressure pumps for high pressure pump protection. 

We highly recommend using an internal in-tank pump due to noise and reliability concerns.

Fuel Pump Internal: Bosch #69225 or equivalent should only be used. A new fuel sock , (Bosch #68001) is also required as any trash entering the pump will destroy it in short order. The sending unit must be modified with a bulkhead connector for the fuel pump and ground and can be accomplished with instructions from some Corvair websites for electric fuel pump conversion. This bulkhead connector from Revolution Electronics is recommended for an easy conversion.  You can also fashion your own bulkhead connector using “JB” weld, but be sure to use the special wiring designed for for submersion in fuel.







Fuel Sending Unit w/Pump:   First, Insert the fuel bulb and then bend the filter edges inward so the pump can be installed after the bulb.  The pump should mount up and and will need the ring attached to secure the sending unit.  Remember to install new rubber seal on the tank to sending unit to prevent future leaks. 

Fuel Sending unit with “S” tube attached (Not included in kit)

Return Fuel Line Hole:  You will need to drill a 3/4″ hole next to the factory hole for the return fuel line.  This support beam is double walled and will require a bit long enough to reach through.  Be careful not to drill to far in and damaging the fuel tank.

Hole with Ground wire using same hole

Fuel Line Return:  It is recommended to remove the fuel inlet nozzle *neck”, braze in a 5/16″ steel tube (2″ in length) and attach to the return line.  An alternate way would to drill and install grommet with fitting as as it will not require brazing, but the neck must still be removed.  Excess fuel will flow from FPR to tank to be recycled through system. Line must be brazed/epoxied in some leak proof way of routing fuel back to tank in a manner that allows for reassembly of the nozzle back into the Corvair fuel door/slot opening.  DO NOT PERFORM WHILE ON THE CORVAIR – IT MUST BE REMOVED.


Fuel Pressure Regulator/Filter:  This Regulator was chosen for its compactness, GM design, price and its dual function as a filter.  This is the slip-on type of connector for the main feed and the “IN” and “RET” lines have been modified to accept rubber fuel line.   The feed line from the tank sending unit is connected by HP rubber hose and clamp attached to an “S” tube.  The “S” tube is then connected to the FPR “IN” nipple by 3/8″ HP rubber hose and worm clamp.   Return lines are connected by HP rubber hose from the FPR  “OUT” to the return on the filler tube.  Remove the tunnel pan to expose the existing fuel line and cut the line where it will allow enough room to connect the HP hose to the line.  Use a device (flaring tool) that will install a bubble or bump on the line that will not allow the HP hose to back off under pressure.  The other end of the 5/16″ line connects at the rear of the engine bay and will be connected to the engine “T” adapter fuel line.

FPR Mounted and Connected

“S” Fuel Tube from Sending Unit to FPR “IN”

Fuel line from engine bay “T” to Fuel line

Factory Fuel line in Tunnel

USE ONLY HIGH PRESSURE EFI RUBBER LINE.  All others will fail and when they do fail you will  have pressured fuel spraying on the exhaust system.   This is one of the last things you want to “Cheap out”  on as you will lose your car and maybe something more valuable.

Installing Engine Fuel Lines:  The fuel lines to the TBIs are 1/4″ steel with double flare ends and connect to our fuel injector adapter.  Normal amount of Torque is necessary to install the fuel lines to the Fuel “T” and normally tightened to where they will not leak. ALWAYS use Line wrenches and proper tools to prevent fuel leaks. The lines are pre-bent to accommodate routing, but can be bent slightly for ease of installation or customer preference.   Fuel is under 58 lbs of pressure and leaks can ruin you day, so always think safety when working around fuel.


Taken while being installed

Engine Temp Sensor:   This is a thermistor type sensor that screwed into the shroud bolt location at #4 plug wire.  Install this sensor before installing the TBI to permit routing and tighten to 15ft lbs. Ground to the screw located next to the Carb pad and route wires so they will not interfere with throttle body operation.  This sensor tells the ECM if the engine is cold, warm or hot, and also adjust the timing when higher engine temps are indicated.

Install the Throttle Body Units:  Use gaskets for a good seal along with the insulator on both sides as the linkage will “bottom out” on engine tins if the insulator is not installed.  You should install the thin gaskets (not thick) along with the insulator as the thickness of these are pre-engineered on the Corvair for linkage height. 

The TBI will be installed as a unit already assembled and the outside stud will be “shortened” by 1/2″ (course side) and not interfere with the installation of the TBI.  If the stud is too high, it will hit the bottom of the injector bung.  The nut will have to be started on the stud as the TBI is installed. 

The TPS has a factory setting of 10%-20% TPS to allow for linkage adjustments, etc. and should not be software calibrated until completely installed.   If you have to remove the injector for any reason, during reassembly be very careful NOT to over tighten the hold down screws as it will cause the injector to malfunction.  Later designs (May 2019) have sleeves that will prevent over-tightening of the injector and aid in proper alignment.  DO NOT ADJUST THE TPS unless instructed by Tech support.

Install Fuel Pump Block-off:  In most cases the Fuel pump block-off does not need a hold down screw and should be secured by tapping into place.  Remember to remove the pump pump rod from the bore to eliminate another moving part that is not needed. 

Mount Control Panel and Wiring Harness:  The Control Panel should be mounted with the attached “self tapping” screw through the holes provided.  Ensure you have the “stand offs” attached to the rear to prevent bending if the screws are over-tightened.  After the control panel is mounted, attached the ECM, Relays, and MAP sensor as shown in photo. 


Control Panel with item mounted                    The ECM is water resistant, but not waterproof and care should be used to keep water directly away from the ECM.  All connectors are weather pack or water tight, but care should always be used with liquids and electronic components.   The Fuel pump connector is a spade terminal and needs a wire ran to the pump(s) and is not included in the harness.  Black heat shrink tubes are included in kit to seal spade and bullet terminals and will seal after heated (do not use open flame).  They should only be installed after installation and testing has been completed as they will need to be removed to open connection.  On FC/Vans, the ECM will be mounted mounted on the firewall along with relays and MAP sensor.  The Control Panel  is mounted in the old external regulator location for late model cars (1965-1969).  You may modify your location and route, but cutting the wiring harness violates your warranty. 

Connect Map Sensor:  The MAP sensor is mounted on the Control Panel and push green weather-pak connector until fully seated. 

Trigger Wheel:  The 36-1 trigger wheel is designed to be bolted to the front of the Harmonic Balancer using 3/8″ bolts with a spacer between the HB and the trigger wheel.  You can install the trigger wheel first then install the HB with the trigger wheel attached.  If your HB is already installed on your engine, you can attached the trigger wheel without removing the HB.  It is usually best to put the bolts, and spacers on the trigger wheel as to be installed and use light glue or heavy grease to hold the spacers in place until the bolts are tightened.  The crank pulley used on early model and low HP models are attached to the provided bolt holes, but the spacers are not required.  The trigger wheel is mounted with the engine at 0 degrees and the open slot at approx 10 o’clock position  (to the left of the degree indicator).

Install Pickup Sensor Bracket:   The sensor bracket is mounted to the existing bolt hole for the Corvair fuel pump hold down.  It should be mounted reasonably level and may be bent slightly for correct alignment.  A/C versions of this trigger wheel need to be mounted to the outer ring of the harmonic balancer and will require you to send us your Harmonic Balancer for modification.


Connect Throttle Position Sensor:  The TPS is located on the front of the driver’s side TBIU (not mounted) and is connected with a weather-pak 3 conductor connector.  After the wiring harness and TPS is connected, It is now time to calibrate your TPS. (Future Video and instructions go here)

Connect Injector Electrical Connectors:  The injector connectors are the GM LS type and are push and click to connect.  They have a clip on the side to disconnect.

Test for Fuel leaks:  You can bypass the fuel feed to pump wire directly to the battery or other 12V ground source and check for leaks.  The Fuel Pressure Regulator will direct fuel back to maintain the proper fuel pressure.  Have a fire extinguisher and a friend handy for this test. Having a leak free system fuel system is very important for operation and your safety. 

Connect Fuel Pump Feed Wire:  The very last item to connect to prevent accidental fuel spillage and fire danger during testing or accidental activation of the ECM. 

Alternator In-Line Diode:  Installing the Diode will prevent a “continue to run” situation after the ignition is turned off.  This is caused by the ALT lamp in your dash which has just enough resistance to keep the relay open, in-turn keeping 12V to the engine through the #1 relay. For detailed instructions, click here ALTERNATOR DIODE


Idle Air Control Valve:  The IAC valve assembly is placed inline by cutting the PVC hose and inserting at this cut.  The bottom of the IAC assembly is route by vacuum hose to fresh air breather/cleaner.  The Idle control box is mounted to the passenger’s side throttle body.   *An optional Idle advance purge valve for A/C models should also be used in conjunction with the IAC to maintain and supplement the idle levels during compressor engagement.  This valve is NOT controlled by the ECM, but by the 12VDC supplied to the compressor. 

Install Guides for the following ignition options.

Install TSP Distributor

Install Pertronix/Factory Distributor:  

Install Corvair Distributor w/Vag Coil:  

Install GM Smart Distributor-less Ignition:


Revised:  7 Apr 2019


Brown EFI systems are intended for off-road use only.