Holley's dual sync distributors were designed to work with the new Sniper EFI system.
Sniper EFI has the ability to control ignition timing.
It's an optional feature, not required for the normal operation but by enabling timing
control, you'll get more precise timing and a better idle quality, I'll show you how to
install it now.
Holley dual sync distributors come with a hardened steel distributor gear.
It's compatible with most camshafts with the exception of billet cams.
If you have a billet camshaft, we recommend you use a bronze gear.
If your unsure of your cam's construction I recommend you contact the camshaft manufacturer
and follow their recommendations.
Before we begin the actual installation, you first need to configure the ignition settings
using the start up wizard and your three and a half inch touch screen.
You'll need to turn your ignition system to the run position but don't crank the engine
yet.
On the Sniper home screen go ahead and select the wizard's icon.
Next you'll need to select the part number of the Sniper throttle body that your using.
The wizard is going to ask how many cylinders your engine is, we're running a V8.
Go ahead and select the engine displacement by sliding the curser and then click next.
Now the wizard would like to know the target idle speed, we're running a 4 speed so we're
going to go ahead and select 750 RPMs for our target.
The wizard would also like to know what style cam we are running, whether it's a stock,
street strip or a race style.
We have a stock cam.
Sniper is capable of controlling Nitrous, we don't have Nitrous on this engine so we're
going to select the none option.
Now the wizard would like to know what type of ignition system we are running.
The steps for both a magnetic and dual sync option are the same, I'll walk you through
those now.
The first thing it's going to ask is whether or not your going to control timing, in this
senario, yes we are controlling timing.
Now it wants to know what you want the ignition timing to be at wide open throttle, we'll
be conservative and select 32, click next, go ahead and click the start icon and the
wizard will begin installing a calibration based on the information you just provided.
When prompted turn the key off and then back to the run position to complete the calibration
install.
Once you've completed the ignition system configuration, we can go ahead and begin removing
our distributor.
First you'll need to remove the negative battery cable from your battery.
Disconnect the power and ground wires from your inductive coil.
If you have an HEI, remove the power wire and the connecting harness from the distributor
cap.
Next you'll need to rotate the crank shaft until it reads 50 degrees before top dead
center on the compression stroke of the number one cylinder.
You can verify that your on the compression stroke of the number one cylinder by tracing
the plug wire from the number one cylinder back to your distributor cap.
If you remove the cap, the rotor should be pointed in the vicinity of the number one
plug wire.
Another way you can verify that your on the compression stroke is to remove the spark
plug wire and the spark plug from the number one cylinder, put your finger into the spark
plug hole and as you rotate the engine you should be able to feel air being pushed out.
Go ahead and remove the cap and wires that way we can determine the rotation of the rotor
as we rotate the crankshaft.
You'll need to know this later on.
Although it is not required, removing the spark plugs from the cylinder heads will make
it easier to rotate your engine.
If your harmonic balancer isn't marked all the way out to 50 degrees, you can use a tape
measure to measure the diameter of your balancer and determine whether it's a 6, 7, or 8 inch.
Use the chart included in the instructions, from the 0 mark, measure the appropriate distance
and make a mark on your harmonic balancer.
Go ahead and disconnect any remaining wiring or vacuum hoses that may be still attached
to the distributor.
You can loosen and remove the distributor hold down now, and once that is complete,
your distributor should lift out.
Don't forget to go ahead and check and make sure the new distributor seats fully and doesn't
bind or bottom out on the oil pump drive.
A quick way to check this is to instal the new distributor without the gasket and make
sure it seats fully on the mounting surface.
If it doesn't fully seat, your heads or engine block may have been milled, you'll need to
do a little further investigation.
Holley does offer a dual sync distributor, part number 565-104, that has an adjustable
slip collar.
Follow the instructions to ensure proper gear engagement.
If everything checks out, you can go ahead and remove the distributor and install the
gasket.
If your engine has been previously just apply some oil to the gear.
If the engine is new or has not been run for a while, go ahead and coat the gear with paste
or break in lube.
Now we can install our dual sync.
Remove the cap and position the rotor so it's pointed in the direction that you'd like to
designate as the number one cylinder.
The rotor will rotate slightly as you install it so if the rotor is not pointed to the spot
that you planned, you'll have to lift up the distributor and rotate it slightly until it
points to the correct spot.
You can designate any position as the number one plug location but it may be necessary
to rotate the oil pump shaft to get it to mesh with distributor shaft.
You can do this with a long flat blade screw driver or wrench, be sure the distributor
is fully seated before proceeding.
Now you need to plug in the optional adapter harness, part number 558-493, it plugs directly
into the 10 pin connector coming from the dual sync.
The pink wire, needs to be run to a clean 12 volt switch source and you can connect
the purple and green together from the connector that comes from the Sniper wiring harness.
If you plan on controlling timing using your dual sync distributor, you'll need to wire
in the coil driver, the pink wire goes to switch 12 volt ignition source, the black
one goes directly to a ground and the white one needs to be spliced in with the white
wire thats included in the auxiliary harness.
The gray wire, you can run directly to the negative terminal on your inductive coil.
Another way that you can control ignition timing using our Holley EFI dual sync distributor
is to connect it to a capacity discharge box like an MSD 6AL.
Using the included auxiliary 10 pin harness connector, connect your white wire directly
to the CD box.
Once you finish making all these connections, you can go ahead and reconnect the negative
battery cable directly to your battery, but you'll want to leave the positive wire at
your inductive coil disconnected for now.
Now we'll need to turn the key to the run position and power up our Sniper and our dual
sync.
With the distributor cap removed, locate the crank sensor as well as the crank and cam
LEDs.
Note that LED on represents digital falling and LED off represents digital rising.
Slowly rotate the distributor housing but do not rotate the crank shaft.
Slowly turn the housing clock wise until the crank LED just goes off.
Now turn the housing counter clock wise until it just comes back on.
For engines with a counter clockwise rotor rotation, you'll first need to turn the distributor
housing until the block crank sensor lines up with your rotor.
Now slowly turn the distributor housing counter clock wise until the crank LED goes off.
Now you'll need to turn it back clock wise until the crank sensor just comes on.
Go ahead and reinstall your distributor hold down, and lightly tighten it.
Once you've completed this step, you can go ahead and verify that the rotor is pointed
in the direction that you want it to designate as the number one cylinder.
You'll also need to verify that the harmonic balancer is still 50 degrees before top dead
center.
Make note of the rotor position as you install the new cap, designate this as your number
one cylinder.
Starting with the number one terminal, install the rest of the plug wires according to your
engine's firing order.
If you are running an HEI distributor before you installed the dual sync, you'll need to
install an inductive coil.
Find a suitable mounting location, connect the gray wire from the coil driver directly
to the negative terminal on the coil, and your switch power wire will go the positive
side of the coil.
Tighten these connections now and install the coil wire from the coil to the distributor.
We'll now need to verify our static timing using the three and a half inch touch screen
and the timing light.
Do this by selecting the tuning icon on your home screen.
Select system, then static timing.
Now slide the curser to 15 degrees and click set, verify that you have 15 degrees at timing
before top dead center at your harmonic balancer with a timing light.
If the balancer does not read 15 degrees before top dead center, it may be necessary to loosen
the distributor and adjust it accordingly.
Don't forget to re-tighten it when you are done.
Once you have verified that you have 15 degrees of timing, go ahead and click clear on the
handheld.
This completes the static timing verification process and the Sniper ECU is now controlling
the timing.
Now that the timing has been verified, the installation of your Holley dual sync distributor
with Sniper EFI is now complete.
To see the complete, step by step installation of EFI on our 1967 Camaro, visit the Holley
performance channel on Youtube.
Thanks for watching, for more information on Holley's dual sync distributor or Sniper
EFI, visit our webpage at Holley.com