Holley EFI
Magnetic & Hall-Effect Crank/Cam Sensor Setup
If your crank or cam sync unit isn't transmitting a signal, troubleshoot the cam sensor, wiring, reference voltage & ground, reluctor,
alignment, air gap (LINK), radial run-out problems (LINK), etc. If a regular datalog indicates an "RPM Error" when scrolling through
the problem area, then it's time for a System Log to confirm which sensor flatlines. FYI: Crank & Cam A/D means Analog To Digital.
It's not the +5V reference supply voltage. Troubleshooting 3-wire Hall-Effect sensors:
http://www.wellsve.com/sft503/Counterpoint3_1.pdf (Understanding/Troubleshooting Hall-Effect Sensors - "Troubleshooting", Page 2)
Record a System Log to verify crank & cam sensor signals. Check mark the "RPM", "Crank" & "Cam" channels. Look for a uniform,
uninterrupted crank or cam sensor signal pattern. The crank or cam sensor signal should never flatline (no pulse) or indicate an
RPM "Error" anywhere. Also, fully charge the battery and ensure the engine is cranking fast enough, at least 100+ RPM. Another
common issue, is trying to analyze a compressed view of a long System Log. Zoom In for detail - click & hold at one point of the
datalog, and drag & release to another point nearby. It's best to record short System Logs/Datalogs that capture the problem.
http://forums.holley.com/showthread....s-amp-Datalogs (Datalog & System Log Information)
Originally Posted by Holley "Help" Contents
CRANK/CAM SENSOR INSTALLATION AND SETUP
The following information is used to assist with the proper installation and setup of various crank and cam sensors and hardware.
Most of these settings are setup as a “Custom” ignition type in the software.
NOTE: You should have a balancer that is fully degreed or a timing tape installed on the balancer to perform the following settings.
1.0 CRANK SENSOR SETUP
1.1 Ignition Reference Setup – “one pulse per fire” trigger, Magnetic Pickup
The following shows how to setup the crank signal for a “one pulse per fire” RPM input using either a Magnetic pickup crank trigger or distributor.
A “one pulse per fire” trigger means there is one sensor pulse for every cylinder firing (on a V8 this would be a 4 pulse crank trigger or a 8 pulse trigger in the distributor).
NOTE: In the software, the Sensor Type should be setup as “Magnetic”.
1. Note the Ignition Reference Angle set in the software. This is typically set to a value that is 10° more than the highest timing you will run.
Do NOT set it higher than 75°. 60° is a common value. 60° is used for an example here.
2. Turn the engine over so that it is at the Ignition Reference Angle. For this example it would be 60° BTDC on cylinder #1.
The timing pointer should be indicating 60° BTDC on the crank.
3. Align/turn the crank trigger or distributor so that the sensor is perfectly inline with the trigger.
• For a Magnetic pickup crank trigger, this means the pickup and a magnet should be inline.
• For a Magnetic pickup distributor, this means having one of the reluctor teeth line up with the Magnetic pickup.
4. Tighten every thing up.
5. If you are not using a cam sync (if you are, continue to section 2.1), everything should be set close enough to start the engine.
It is recommended that you disconnect the injectors and crank the engine over.
Look at the timing with a timing light. It should be firing at the cranking timing value shown on the data monitor.
If it is off a few degrees, you can move the pickup slightly, or change the Ignition Reference setting to sync things up.
If you change the Ignition Reference value, note that you must cycle the ignition power for it to take affect.
1.2 Ignition Reference Setup – “one pulse per fire” trigger, Hall-Effect Pickup
The following shows how to setup the crank signal for a “one pulse per fire” RPM input using either a Hall-Effect pickup crank trigger or distributor. A “one pulse per fire” trigger means there is one sensor pulse for every cylinder firing (on a V8 this would be a 4 pulse crank trigger or a 8 pulse trigger in the distributor).
NOTE: In the software, the Sensor Type should be setup as “Digital Rising” or “Digital Falling”.
1. Note the Ignition Reference Angle set in the software. This is typically set to a value that is 10° more than the highest timing you will run.
Do NOT set it higher than 75°. 60° is a common value. 60° is used for an example here.
2. Turn the engine over so that it is at the Ignition Reference Angle. For this example it would be 60° BTDC on cylinder #1.
The timing pointer should be indicating 60° BTDC at the crank.
3. Align/turn the crank trigger or distributor so that the sensor is aligned properly. In the software, the signal should be setup as “Digital Rising” or “Digital Falling”. A Hall-Effect sensor typically uses a “shutter window/wheel” that has “openings” and areas of material that are in close proximity to the sensor that triggers the sensor output. Or it uses a toothed wheel that has “teeth” and “gaps”.
When the sensor sees the edge of an “opening” or a “gap”, this triggers the sensor in a “Falling” manner.
When the sensor sees the first edge of the material or tooth, this trigger the sensor in a “Rising” manner.
To set the Hall-Effect pickup properly:
• If set as “Digital Rising”, the pickup should be located such that the sensor is aligned where the shutter window/wheel or tooth edge first hits the center of the Hall-Effect sensor.
• If set as “Digital Falling”, the pickup should be located such that the sensor is aligned where the “opening” in the window/wheel is or the tooth gap starts (also meaning where the sensor leaves the edge of the shutter window/wheel or tooth edge).
4. Tighten Everything up.
5. If you are not using a cam sync (if you are, continue to section 2.1), everything should be set close enough to start the engine.
It is recommended that you disconnect the injectors and crank the engine over.
Look at the timing with a timing light. It should be firing at the cranking timing value shown on the data monitor.
If it is off a few degrees, you can move the pickup slightly, or change the Ignition Reference setting to sync things up.
If you change the Ignition Reference value, note that you must cycle the ignition power for it to take affect.
1.3 60-2 Wheel
The following covers the installation of a 60-2 crank trigger wheel Holley offers.
Holley offers kits for Small and Big Block Chevy engines to mount the sensor and wheel.
Four different diameter 60-2 wheels are available that can be custom mounted on any engine.
The “60-2” alludes to the fact that crank trigger wheel has 58 teeth with “2 missing”. This is also known as a “58x” wheel.
The “missing” teeth are used as an identification, so the ECU can recognize the exact angular position of the crankshaft.
Having 58 teeth allows the ECU to much more precisely calculate engine speed compared to a trigger wheel with less teeth.
To setup a 60-2 wheel:
1. Rotate the engine to #1 TDC.
2. The software has a parameter called “TDC Tooth Number”. This is typically set to “10”. The example below will use 10 as this value.
Do not set it below a value of 9 for best timing accuracy.
Values higher are acceptable, but you need to make sure the cam sensor is installed appropriately if one is used (see section 2.2).
3. With the engine at TDC on #1 cylinder, the sensor will be positioned such that it is lined up with the “TDC Tooth Number” (for this example 10).
This is the 10th tooth “after the missing teeth” on the crank trigger wheel in the direction that the engine rotates.
Install the crank trigger wheel and align the bolt holes on it such that the sensor will be near this position.
Most all engines rotate clockwise, except for Honda engines which rotate counterclockwise. If you are confused about which tooth this means, put the trigger wheel on the engine and rotate just the trigger wheel (leave the engine at TDC on #1) in the direction the engine rotates. Rotate it until the missing teeth/gap line up to where the sensor will be mounted, then continue turning it and count 10 teeth. Take a marker and mark this tooth. It will be the tooth you need to align with the sensor.
2.0 CAM SYNC POSITIONING
A cam sync pulse is required if you are running sequential fuel injection. This tells the ECU which cylinder is cylinder #1 (or the first cylinder in the firing order as entered in the software). The following describes setting this up for a “one pulse per fire” crank input as well as a “60-2” crank input.
2.1 Cam Sync setup when using a “one pulse per fire” crank input
For a "one pulse per fire crank” signal (e.g. a 4 pulse crank trigger on a V8), the cam sync signal must occur in a specific range to properly identify which cylinder is cylinder #1. If this is not done properly, individual cylinder trims will not be performed on the correct cylinder, or worse, if using individual coils, the wrong cylinder will be fired, potentially damaging the started, flexplate, or worse.
The best way to determine the proper range is by using the following basic formula to determine the crank angle range that the cam identity can occur. An example is give afterwards along with a table that has certain combinations already calculated.
Cam sync location (degrees BTDC #1) = "Ignition Reference Angle" + “A” + (“A” / 2)
“Ignition Reference Angle” = Taken from Crank Sensor Setup in software
“A” = Angle Between Crank Pulses (crank degrees between triggers on the crank sensor)
“A” for a 8 cylinder = 90°
“A” for a 6 cylinder = 120°
“A” for a 4 cylinder = 180°
Using the formula above, plug in the “Ignition Reference Angle” you are using and the proper “A” value depending on the number of engine cylinders.
The location calculated is the “ideal” location and can vary +/- 30° or possibly more.
If you are out of this range contact Holley Tech Service for options.
Example - 8 cylinder with a Ignition Reference Angle of 60°
Cam Sync Location = 60 + 90 + 90/2 = 195 degrees BTDC #1
Cam Sync Location = 60 + 90 + 45 = 195 degrees BTDC #1
195° would be the centrally "perfect" location for this specific example.
However, this location can vary by +/- 30 degrees from this nominal target value with no issue.
Number of Cylinders Ignition Reference Angle Cam Trigger Location Range (BTDC #1)
4 60 330 +/-30 degrees
6 60 240 +/-30 degrees
8 60 195 +/-30 degrees
NOTE: If it is mechanically not possible to install the cam trigger in the proper location, the engine firing order can be changed to compensate. For details on this, contact Holley Tech Service at 1-866-GOHOLLEY.
2.2 Cam Sync setup when using a 60-2 crank input
When using a 60-2 crank sensor wheel, this cam sync signal trigger MUST occur:
• Before cylinder #1 is at TDC on the COMPRESSION STROKE, make sure that it is not occurring on the exhaust stroke.
• It also MUST occur at least 8 teeth (approximately 50 degrees) before the “missing teeth” are read by the crank position sensor.
If the crank sensor is setup such that the 10th tooth after the missing teeth is at TDC,
position the cam sensor such that it's between 110°−250° before TDC on cylinder #1.
This will create a proper position.
This cam sync input can be configured as a Magnetic or Hall-Effect (Digital Rising or Digital Falling) input in the software.
Make sure that if you are using a Hall-Effect sensor, you have this setup properly as a rising or falling signal.
2.3 Special Cases
Case 1: Ford Modular Setup in Custom Ignition Parameters
Because the stock location of the cam pulse on the Ford Modular engines occurs about 25° or so after #1 firing TDC, this conflicts with our normal convention (crank gap immediately after the cam pulse corresponds to first cylinder in firing order). So you have to juggle the firing order. The cam pulse is circled, and the following crank gap has the yellow arrow. Since this corresponds to cylinder 6 instead of cylinder 1, you start the firing order with 6. 6-5-4-8-1-3-7-2 being the result. Below is a graphic with some offset and filtering settings (that only have an effect with the J+ ECUs). It is important to realize you do NOT have to juggle the firing order when you are using the “canned” ignition type, only the Custom Ignition Type. Also, ensure you enter the correct Dwell Time for the ignition coils you're using.
Case 2: Using a 1 Pulse/Fire Crank Trigger with a Chrysler NGC Cam Pattern
The Chrysler NGC cam signal is a pulse width encoded pattern. The ECU looks for a certain pattern and you can think of it as throwing a flag at a certain point in the pattern when it recognizes it. This normally happens at the rising edge of the cam pulse that is nominally about 15° before #1 firing TDC. Ideally this would happen about 180° before firing TDC so it would fall into line with our current crank/cam reckoning convention for 1 pulse per fire crank patterns (the second crank tooth after the cam pulse corresponds to the first cylinder in the firing order). Since it does not, you have to juggle the firing order. The timing of the cam decode “event” is circled and the second crank pulse thereafter is marked with the yellow arrow. Since this corresponds to cylinder 4 instead of cylinder 1, you start the firing order with 4. 4-3-6-5-7-2-1-8 being the result.
Case 3: Using a 1 Pulse/Fire Crank Trigger with a GM 4x Cam Pattern
The GM 4x cam signal is a pulse width encoded pattern. The ECU looks for a certain pattern and you can think of it as throwing a flag at a certain point in the pattern when it recognizes it. This normally happens at the falling edge of the cam pulse that is nominally about 210° before #1 firing TDC. Luckily this falls into line with our current crank/cam reckoning convention for 1 pulse per fire crank patterns (the second crank tooth after the cam pulse corresponds to the first cylinder in the firing order). The timing of the cam decode “event” is circled and the second crank pulse thereafter is marked with the yellow arrow. However, you will notice that this graphic is with a crank pulse that happens at 60° before TDC. It is very important that the crank pulse is not retarded past the cam edge that is circled, nor too close that would result in the edges crossing during a transient event. Because of this, you will probably not want to use an ignition reference angle less than 40° or so. It is also important to record a system log after the engine is fired to make sure you have adequate margin since there is variation in the timing of cam pulses.
Case 4: Using a 1 Pulse/Fire Crank Trigger with a Factory GM LSx 1x Cam Pattern
To properly phase the cam trigger location in reference to cylinder #1 compression stroke, setup the configuration as follows:
Engine Firing Order = 7-2-6-5-4-3-1-8
Ignition Reference Angle = Set between 40°-60°
Cam Sensor Type = Single Pulse
Sensor Type = Digital Falling
Originally Posted by Danny Cabral
This information above, is also found in the Holley EFI software; click on "Help", "Contents" & "Crank & Cam Sensor Setup".
http://documents.holley.com/techlibr...10555rev17.pdf (Holley EFI Wiring Manual)
http://forums.holley.com/showthread....=7592#post7592 (Datalog & System Log Information)
http://documents.holley.com/techlibr...__statuses.pdf (Sensor Diagnostics & Statuses)
http://documents.holley.com/crank-camsensorreq.pdf (Crank & Cam Sensor Requirements)
http://i1206.photobucket.com/albums/...re/CamSync.jpg (Pictorial diagram of a 4x crank trigger and 1x cam sync.)
http://www.yellowbullet.com/forum/sh...0#post26386690 (Incorrect Digital Falling Signals - 4x Crank & 1x Cam)
http://documents.holley.com/199r10898.pdf (Holley EFI 36-1 Crank Trigger Kit Instructions)
http://documents.holley.com/199r10562.pdf (Holley EFI 60-2 Crank Trigger Kit Instructions)
http://www.wellsve.com/sft503/Counterpoint3_1.pdf (Understanding/Troubleshooting Hall-Effect Sensors - "Troubleshooting", Page 2)
http://forums.holley.com/showthread....ons-Holley-EFI (FAST Dual Sync Distributor Wiring & Setup Instructions)
http://forums.holley.com/showthread....nition-Harness (Cadillac Northstar Ignition/Coil Pack Wiring)
http://forums.holley.com/showthread....7990#post47990 (Wiring Modification To Pin B20, "EST +12V Output")
The following information is only if you decide to put timing marks on the damper (#1 cylinder TDC identification & 30° example):
If necessary, use a spark plug hole type piston stop & degree wheel to first establish TDC, then make a damper mark at 30°.
FYI: This procedure can also be used to correctly install/position a crank trigger kit/cam sync unit at 60°, 180°, 195°, etc. (Link).
If using spark plug type piston stop, some people remove rocker arms from #1 cylinder to avoid the risk of valves contacting tool.
Also, remove all spark plugs for easy turning force (no compression) to prevent damage from harsh piston-to-tool contact.
There's nothing wrong with installing a timing tape. Just ensure it's the correct one for your diameter damper.
You don't necessarily need a timing tape, because both timing synchronizations can be performed with one timing mark.
Multiply the damper diameter by 3.14159 (Pi), then divide by 360°. The answer is the distance in inches for one degree.
For a 30° timing mark, multiply this value by 30. Cut out this distance on a strip of paper to avoid a straight line measurement.This is the difference between "Digital Falling" and "Digital Rising". Digital Falling is much preferred:
I've data logged the difference on the same Hall-Effect sensor, and Digital Rising had RPM errors.
Just some reference notes pertaining to crank trigger adjustments:
The crank sensor sliding bracket, now does the task that turning the distributor once did.
With a crank trigger, turning the distributor only adjusts rotor phasing.
MSD has a good video on why rotor phasing is important:
http://www.youtube.com/watch?v=aWMlNwGW0tM (MSD Tech - Rotor Phasing Video)
http://documents.msdperformance.com/8644_tb.pdf (MSD Rotor Phasing Document)
Excerpt from Holley EFI manual:
NOTE - It is not advised to use a magnetic pickup distributor to directly feed the magnetic trigger input of the ECU. If the
magnetic pickup distributor is connected to the ECU via the inductive pickup trigger wires, the pickup/rotor/cap phasing
must be corrected. This operation may require a phaseable cap or rotor or possibly machining to the distributor and is
therefore beyond the scope of most users. Even with the phasing corrected, the electrical noise inside the cap
(due to the high voltage cap & rotor terminals) may be strong enough to cause electrical noise interference.
It is advised to use a crank trigger system or a computer-controlled distributor.
Ignition Timing Cylinder Sequence Verification
Ensure the Firing Order is entered correctly in Ignition Parameters (System ICF).
Before the initial start, disconnect the fuel injector harness and verify
at least, the first four cylinders in the firing order using a timing light.
If your cylinders are firing in 90° intervals BUT in the wrong sequence,
the coil harness is connected wrong (at the ECU or at the coil packs).
Hopefully you have a fully degreed balancer or at least markings every 90°:
1st cylinder, in firing order, should fire at 0° (or 15° - add whatever your cranking timing is)
2nd cylinder, in firing order, should fire at 270° (or 285° - cranking timing added)
3rd cylinder, in firing order, should fire at 180° (or 195° - cranking timing added)
4th cylinder, in firing order, should fire at 90° (or 105° - cranking timing added)
5th cylinder, in firing order, should fire at 0° (or 15° - cranking timing added)
6th cylinder, in firing order, should fire at 270° (or 285° - cranking timing added)
7th cylinder, in firing order, should fire at 180° (or 195° - cranking timing added)
8th cylinder, in firing order, should fire at 90° (or 105° - cranking timing added)
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