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How To Install Holley Sniper EFI

Well by now I’m sure you’ve all heard of Holley’s
new Sniper EFI system. Today we brought the 67′ Camaro in to show
you just how easy it is to install, but first let’s go take a look at what comes in the
kit. Here’s what you’ll get when your new, Sniper
EFI kit arrives. The first thing you’ll find is a start up
guide and detailed instructions walking you step by step through the installation process. The Sniper throttle body, it’s a 4 injector
unit capable of supporting up to 650 horse power. It has a built in ECU so there’s no external
boxes to mount. There’s also a serviceable throttle position
sensor and idle air control motor to simplify the installation. The throttle body also houses a fuel pressure
regulator that’s pre-set to 58.5 PSI. There’s a 3 and a half inch touch screen color
LCD. This makes it easy to navigate the start up
wizard and monitor engine sensors. The wide band O2 sensor allows the system
to learn as you drive. The main power harness, which contains the
4 wires that you’ll need to connect to power up your new Sniper EFI system, as well as
the fuel pump wire that’s powered by our 40 AMP relay. An auxiliary wiring harness, you use this
when your controlling electric fans or Nitrous relays. It’s also used when your connecting the coil
driver. Throttle and transmission brackets with mounting
hardware. There’s a base gasket with mounting studs
and nuts as well as an air cleaner stud with base gasket and miscellaneous throttle and
transmission linkage studs. The coolant temp sensor, which provides the
ECU with vital information on your engine’s operating temperature. A stainless steel, no weld O2 bung with high
temp gasket and quality clamps to keep it in place. Plenty of split loom to protect your wiring. There’s even some zip ties and miscellaneous
wire terminals to help to complete the wiring installation. Now that we know everything that’s included
in our kit, we can go ahead and begin our installation. Remember, safety first, whenever your doing
any work on your fuel or electrical system it’s always best to remove the negative battery
terminal before proceeding. Now we can start removing the carburetor. It’s always a good idea to go ahead and label
all the vacuum lines before you get too far. On this application we’re just going to use
the PCV valve, and the vacuum advance for the distributor, go ahead and mark them now. Next you can go ahead and remove the throttle
linkage, as well as the return spring and put them out of the way for safe keeping. You also need to go ahead and connect your
fuel line. Be sure to use a rag to catch any of the excess
fuel before you remove it. I went ahead and removed all 4 nuts from the
carburetor studs, now we’re ready to pull it off. Be careful when your lifting it off that you
don’t spill any fuel. I removed the old carburetor and the spacer,
now you can install the new gasket supplied in the kit, and now we’re ready to install
the throttle body, make sure you don’t pinch any wires when you are installing the intake. Now you can fasten the throttle body to your
intake, use the studs, washers, and nuts found in your kit. I went ahead and drained some of the coolant
so I replace the coolant temp sensor, or the CTS, with the one provided in the kit. This sensor let’s the ECU know when the engine
has reached an operating temperature of at least 160 degrees fahrenheit, triggering learn
mode. There are various locations that you can install
your temp sensor, depending on the make and model of your engine. On this small block Chevy I decided to go
to the passengers side cylinder head to install ours. The sensor comes with sealant already pre-applied,
but since the OEM sensor was larger in diameter than our replacement one, I’ll have to use
this bushing and some PTFE paste to seal it up. Now that the CTS is installed, we can go ahead
and work on our throttle linkage. Every senario is different, that’s why the
Sniper kit includes a variety of mounting studs. Check out our how to videos at the Holley
performance Youtube channel for more tips and tricks on connecting your throttle linkages. Don’t forget to reconnect your vacuum lines
and your throttle return spring when your finished. Next we’ll install the Oxygen sensor, it should
be mounted as close tot he engine as possible, but after all the cylinders have merged. This holds true whether your using a manifold
or a header for your installation. If your using a long tube header, it should
be mounted at least 1-10 inches after the collector flange. Make sure you have at least 18 inches of exhaust
after the O2 sensor, in this case we have a full exhaust so we don’t have to worry about
it. Our Sniper kit included this handy, stainless
steel clamp on style O2 bung, it also includes a high temp gasket and quality clamps to seal
it all up. First we need to find a suitable location
to mount the O2 sensor. Be sure to mount your O2 sensor in a position
that’s at least 10 degrees upward from horizontal, this prevents condensation from collecting
on the tip of the sensor, which can shock and damage your O2 sensor on start up. Once you’ve found your location, you can take
a marker, and outline the hole. Next you’ll have to take a punch to get a
start for drilling. You can use a three quarter inch drill bit
or a step bit to help enlarge the pilot hole. Go ahead and position the gasket and the stainless
steel bung, slightly tighten them down, install the wideband O2 sensor that’s included in
your kit. Make sure that the O2 sensor doesn’t interfere
with the drive line. If everything looks good, you can go ahead
and tighten everything down. Connect the O2 sensor to the throttle body
and secure the wires to prevent contact with moving parts and high heat areas. Now that we’ve got the Oxygen sensor installed,
I’d like to show you just how simple it is to wire Sniper EFI. There’s only 4 connections you’ll have to
make, battery positive, battery negative, a switch 12 volt ignition source, and your
coil input. One of the most common mistakes that we find
is the fact that people don’t read the instructions closely. The power wire and the negative wire that
are found in the wiring harness need to be connected directly to your positive and negative
terminals on your battery, never to a junction box, cut off switch, or fuse panel. You’ll need to take some time and plan out
the routing for your wiring harness. Make sure to avoid high heat areas like the
exhaust and ensure that you have plenty of wire length to make your connections. The first thing you’ll need to do is connect
the main wiring harness to the corresponding connector that comes from the throttle body. On this car, we wanted to retain the stock
factory battery cable terminals to keep a stock look, so I purchased a dual terminal
style battery which will allow me to use the OEM terminals on top but gives me a dedicated
connection on the side post for the power and ground for the Sniper wiring harness. Strip the wire and install one of the supplied
terminals using the proper crimp tool. Use the heat gun to shrink the protective
coating that’s found on the terminals. Do this to both the red and black wires. Go ahead and connect your positive power wire
directly to the battery, but don’t connect the negative yet. Next you’ll have to find a dedicated 12 volt
ignition source to connect the pink wire to, I’ll show you how to do this now. I found a clean, switched ignition source
right here on the factory fuse panel. Check this by connecting a test light and
cycling the ignition switch between the run and off positions. It’s a good idea to go ahead and go a step
further, and verify that you have 12 volts during the cranking process. Do this using the multi-meter, by setting
it to the DC voltage mode. Connect the leads and check the voltage in
the run position, it should read somewhere near 12 volts. Now check the voltage again while cranking
the engine, there should be around 9-10 volts while cranking, due to the extra load from
the starter. I have just over 10 volts so this should be
a good location to connect my pink wire. While I’m down here under the dash, I’m going
to go ahead and run the cam bus cable from our 3 and a half inch touch screen through
the fire wall and into the engine bay, so we can make the connection to the lead coming
from the throttle body. Be sure and use rubber grommets to protect
any wires from damage. The blue wire is for your fuel pump, it has
a built in 40 amp relay to directly power the pump, go ahead and run this back to the
fuel pump now, being sure to avoid heat and sharp edges. Once you’ve finished routing your wires and
making the proper connections, be sure to go back and connect them properly with either
zip ties or insulated clamps. If your running a stock mechanical advanced
distributor with inductive ignition coil, simply connect the yellow coil input lead
from the sniper to the negative terminal on your coil. If your running a large cap HEI style distributor,
the yellow coil input wire needs to be connected to the tac terminal found on the side of your
distributor cap. For this build, we decided to go ahead and
upgrade our ignition system to Holley’s dual sync distributor. The Holley distributor connects to our wiring
harness using the optional adapter, part number 558-493. Since we’d also like to control ignition timing,
we’ll go ahead wire in the included coil driver module. For detailed instructions on installing Holley’s
dual sync distributor, check out our how to video. Now that we got the Sniper throttle body installed,
made all the proper wiring connections and installed the O2 sensor, we can focus our
time on the fuel system. There’s a lot of different options when it
comes to plumbing your vehicle for Sniper EFI, but Holley’s made it easy with our master
kits. The Master Kit includes a fuel pump, pre and
post fuel filters, 20 feet of vapor guard hose with fittings, and it even has a block
off plate for your mechanical fuel pump. The 67′ Camaro has plenty of space between
the fuel tank and the rear differential, in your case it may not be as much. I was able to make a bracket that I hung from
both of the tank straps that I can mount both the fuel pump and the pre and post filters
from. Next you’ll need to connect the fuel tank
outlet to the inlet on the pre filter using a piece of vapor guard hose. You’ll also need to connect the post filter
outlet to the supply line running to the engine bay. Make sure when you are running your return
line and supply line that you protect the hose from any high heat or sharp edges along
the way. If there’s not enough space between your tank
and differential, another possible location for the fuel pump is right here on your frame
rail. Just remember, the pump should be mounted
lower than and as close as possible to the fuel tank for the best performance and service
life. Our Holley inline pumps like this 12-600 unit
fit nicely and provide a clean look. Another great alternative is to replace your
fuel tank with one of our new Sniper EFI conversion tanks. The tanks come complete with a pair of tank
straps, fuel level sending unit, fuel level float, mounting gaskets and hardware for the
pump and sending unit, complete detailed instructions, the fuel pump module hanger, an intank fuel
pump, filter sock, a roll over valve, and clamp and zip ties to mount the pump. If you have a custom fuel tank or there isn’t
a replacement option available for your particular vehicle, Holley’s new drop in modules are
an excellent way to add an intank fuel pump to your existing fuel system. You’ll need to run a return line from the
Sniper throttle body in the engine bay, back to your fuel tank to return the fuel. There’s multiple locations where you can install
this bulkhead, I’ll show you some options here. The first option is obviously to install it
directly into your fuel tank. Now to do this you’ll have to remove the fuel
tank from the vehicle it’s self and then you’ll have to have a professional fully clean it,
that way there’s no explosion hazard. The second option is to actually install it
into the fuel sending unit. Most of these are removable and have plenty
of room. Just make sure you don’t obstruct anything
on the backside and that you have plenty of room to tighten the nuts. The third option is to actually install it
into the fuel filler neck it’s self. Most of them are removable, therefore there’s
no explosion hazard, plus you can keep all the shavings from entering the fuel tank itself. Just simply drill a hole making sure that
you can get to it with the backside of a wrench and install it in the fuel filler neck itself,
it’s that easy. If you don’t have the room, or you simply
don’t want to run a return line all the way from the engine bay back to your fuel tank,
well Holley has a solution for you, it’s our filter regulator. It can shorten your return line dramatically,
it has a replaceable filter element and a built in fuel pressure regulator that’s pre-set
to 55.8 PSI. This is what a typical installation using
our Holley filter regulator will look like. Notice there is only a single supply line
and a shortened return line. This eliminates the need for a regulator in
the engine bay, plus there’s one less filter to purchase and mount. If your using one of the Holley filter regulators
in your setup, then you can install a cap on the fitting at the fuel pressure regulator
on the throttle body. Next we need to supply power to our fuel pump. Connect the blue fuel pump wire that comes
from the Sniper wiring harness directly to the positive side of your fuel pump. You also need to make a connection from the
negative side of the fuel pump either directly to the battery negative terminal or a good
clean chassis ground. Now we can work on the fuel connections to
our Sniper throttle body here in the engine bay. We’ll need to run a supply and a return line
from our fuel tank in the back of the car to our Sniper throttle body here in the engine
bay. We recommend that you use a fuel line with
at least a three eighths inch ID for the supply line and five sixteenths ID for the return. There are three inlet options on the Sniper
throttle body that you could connect your supply lines to, but it’s important that the
return line is only connected to the -6 fitting found on the fuel pressure regulator. Before we can connect our supply line to the
throttle body, you’ll need to flush the system. I find it easiest if you leave yourself a
little extra hose and run it directly into a gasoline suitable container. Flushing the supply line prevents debris from
clogging the injectors, causing poor starts, rough idle, poor performance, and even injector
failure. We’ll come back prior to start up and finish
our connection at the throttle body. First let’s reconnect both negative leads
to our battery then I’ll walk you step by step through the start up wizard. 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 you’re 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’ll select the none option. Now the wizard would like to know what type
of ignition system we’re running. If you’re running an HEI or a stock ignition
system with inductive coils, you’ll need to select the coil negative option. Timing control is not available with this
option. If your ignition system includes a CD box
such as an MSD or Accel box, you’ll need to select the CD box option. Sniper EFI is capable of controlling timing. When your running a magnetic style pick up
distributor such as the MSD unit or if your running a Hall Effect distributor such as
the Holley dual sync. The steps for both a magnetic and a 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 the 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. When you turn the key back to the run position,
you should hear the fuel pump come on for approximately 5 seconds, remember we have
our supply line run into a gas can so go ahead and cycle the key another 2-3 times to completely
flush the line. Now we can remove the excess hose from the
gas can and go ahead and cut it to length. Now that we’ve got the fuel system completely
flushed, we can go ahead and complete our connection to the throttle body. Use the fitting supplied and install it on
the hose, tighten your clamp, and make the connection at the throttle body. Don’t forget to tighten your fitting when
you’re done. Now we’ll need to perform the sensor verification
on the hand held. Before you start the engine you’ll need to
verify that all the sensors are operating properly. To do this turn the key to the run position
and listen for the fuel pump. From the home screen select the monitor then
the monitors icon. Now you’ll need to select initial start up. This will bring up a screen showing all the
sensor readings. Engine RPM should be at stall since we’re
not running. Throttle position sensor should be at 0. If you slowly depress the the throttle to
wide open throttle, you should get a reading between 85 and 100 percent. If your reading is lower than 85 percent,
you’ll need to correct any issue preventing the full travel of your throttle linkage before
proceeding. Your map sensor should read between 95 and
102 KPA. Higher elevations can cause the reading to
be as low as 75 KPA. The coolant temp sensor should read the ambient
temperature of the air around your engine, ours is 81-82 degrees. The IAC, we will have to address this after
the engine is warmed up. If any of the sensors are not reading correctly,
you must resolve the issue before the engine is started. While you still have your hand held on the
initial start up screen, go ahead and crank the engine but watch the RPMs, it should say
syncing and the engine should start up. If there’s no RPM signal you either have an
error in the wiring or the system set up. If the engine starts but is idling too low,
it may be necessary to open the idle speed screw slightly until it idles on its own. Go ahead and let the engine run until it reaches
a normal operating temperature above 160 degrees fahrenheit. It’s a good time to double check for any coolant
or fuel leaks now. If you are controlling timing with your Sniper,
you will need to do a static timing check using the touch screen and a timing light. First we’ll need to lock to static timing,
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 of 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 retighten it when you are
done. Once you have verified that you have verified
that you have 15 degrees of timing, go ahead and click clear on the hand held. This completes the static timing verification
process and the Sniper ECU is now controlling the timing. Once your engine has reached an operating
temperature of at least 160 degrees, we can go ahead and set the idle speed to the RPM
that we selected in the start up wizard. To do this, you’ll need to select the monitor,
multi-gauge, then sensor’s icon from the home screen. With your vehicle in neutral and the parking
brake applied, adjust the idle screw, closed or open, until the IAC reads between 2 and
10 percent. If your TPS reading goes above 0 percent once
this procedure is done, you’ll need to cycle the ignition switch off and then back on to
reset the TPS to 0. Since the Sniper EFI is the same height as
the carburetor that we already removed, there shouldn’t be any hood clearance issues, in
fact, in most cases you can actually reuse the factory air cleaner. With Sniper EFI we were able to keep the old
school look but now have all the benefits of EFI hidden right under our air cleaner. Congratulations, you’ve just installed your
Sniper EFI system, all that’s left to do now is simply take the vehicle for a drive and
let Sniper self tune. Refer to our quick start guide and follow
the instructions under the first drive section to preform the initial self tuning operation. It’s always best to perform the initial drive
in an area that doesn’t have much traffic, that way you can vary the engine load accordingly. It’s also a good idea to have a buddy along
so he can monitor the gauges while you focus on the driving. Thanks for watching, to see more how to videos
or for more information on Sniper EFI, visit our website at

100 thoughts on “How To Install Holley Sniper EFI

  1. Thanks for posting I have just 2 or 3 things I need help on.
    ..the Blue Fuel pump wire. I bought A Tank with the built in pump and ran the 8 gauge wire from the pump along the frame rail to just about the Front Firewall so I can cut it down to reach the Blue wire or do I have to use the Long Blue Wire and take it back to the tank? Or do I just hook up what I have done already to the Blue Fuel pump wire and STOP.
    My truck is A 64 Chevy Fleetside Short bed.
    So Then just proceed with the rest of the install I am assuming Once I connect the rest of the harness that goes to the KEY or whatever I will get A signal to the Blue Wire for ON/ OFF either before or during the install Correct?? Sorry I jumped ahead to the parts I knew I would have questions on.
    SECOND THING I have A Chevy Small Block 87/95 Type Heads there is no port on the head between the number 1 cylinder and number 3 cylinder But I do have A Corvette Style Short Water Pump that has a fitting on top that I have plugged right now can I connect my new Holley Water sensor there instead of the Intake Manifold I have the Street Warrior Dual Plane Intake And I have my traditional Gauge in use at the intake I would prefer not to lose the sender there. Or swap it to the Water pump and move the Holley Water Sender to the Intake so either way I would be happy…Last Question the PCV Valve is in the back on the Sniper Throttle Body can I uncork the Port that is on the Front Bottom of the sniper and Add A NPT Fitting there for my PCV Valve where it is plugged currently? What size is the Plugged Front fitting so I can order the NPT Fitting online.. Aside from that I am good to go Thanks for the Tip on Flushing the Line First I missed that

  2. I have a 69 camaro with a 383 stroker and a street strip cam. My question is while at idle my engine is extremely rich and has troubles idling to my set 850rpm.(it ether idles way high above 2k rpm or goes way low and stalls out)Now at cruise speeds on the road (45 to 55mph) the engine runs perfectly! I guess I need some help pointing me in the right direction to fix my poor idle and very rich idle condition any help would be great! Thankyou!

  3. I purchased a Holley sniper efi a few weeks ago, The unit was garbage it had a bad IAC and the fuel pump was bad all out the box new. The fuel pressure was pulling around 30 psi. The mechanic that installed the holley sniper for me installed 6 snipers before my unit, so he knows what he is doing. He told me 2 of the 6 Holley snipers he installed had fuel pump problems but no issues with the IAC. One of them he had to install the fuel pump inside of the gas tank. I finally contacted Holley, I was on hold for 35 minutes, the tech wasn't helpful on what they can do for me. I haven't received the IAC in the mail yet and I had to pay the mechanic to install a bad Holley sniper unit. I had to buy my own IAC from a 98 Chrysler and I'm waiting to see what they will do with the fuel pump. Is Holley going to reimburse me for the waste of money I had to pay out? highly doubt it. I am very displeased with the Holly sniper unit. I wasn't lucky to get a good unit I guess. Holley get your trash together!

  4. Hello just finished today. 05/28/17
    I had Leaks to solve with the hard line set up on the Fuel ends.I needed the Flare wrench to get the Proper torque on the hard 3/8 ID Steel lines to stop the leaks I have 5/8 ends I have Your Russel Adapter ends #640610. I posted videos on You Tube with my progress. I ran one Gauge for the Hi Side and it is reading 60 PSI with the key on engine running… At the same time The Low Side Gauge read 2 Psi But right at that point I shut it off. I Just remembered I have to verify that I have adequate coolant and tighten the O2 Sensor I might have missed it.
    I Do have a few questions…
    As the Truck warms up to temp…I am using 160 degree thermostat Griffin Aluminum Radiator 15 PSI cap with A Thermal Hayden heavy duty Fan Clutch and full shroud set up fan slightly on the outer edge of the shroud so it moves the air properly.
    Is the 160 Degree thermostat correct to use? It is A fresh rebuilt Stock Chevy with Stock Roller cam and Stock Heads 350/5.7 1987/95 type with your Street Warrior Intake.
    So While running what should the Low side read ? Also what should the pressure gauges read when I shut it down after my first drive? Return to Zero?
    I did not catch the part about using 5/16 Size Return line until till after I had already Run the 3/8 ID Size for the send line and the Return So do I have to Start over with 5/16 ID Steel on my Return line?
    Our Truck is is A 1964 Chevy Fleetside Short bed with the Tank from Tanks Inc.In the rear under the Truck bed between the frame rails. has A Fresh 700R4 Trans and Fresh Rebuilt 12 Bolt Rear with Eaton True Trac 373 gears and stock type 4 wheel Disc Brakes from CPP.
    On the Fuel System I am using #12301 red Aeromotive Pre Filter and the After filter is the Smaller FRAM Filter #G3727 About 24 inches away from the tank they are Wrench type Filters along my inner passenger side frame rail everything leads up to the passenger side Throttle body…
    SO I FIRED IT UP FOR THE 1ST TIME AND IT CAUGHT IMMEDIATELY I MIGHT AD! The Initial Readings from the Sniper Display Gauges were OK thats it…..
    Its been an education for sure very smooth Idle in park. Not quite sure how to post so you guys can see the videos but I am no good at Cut And Paste stuff I am a "monkey see monkey do" type gear head not A computer guy LOL but your welcome to use any of the videos I posted any way you see fit
    Sincerely Jeff A Garcia Riverside CA.
    P.S. Or Let me know how to do it or I will ask a friend
    And By the way MOM LOVES HER SNIPER! She could not believe the difference how fast it Fired Right up No Pushing on the pedal First ETC! This is going to be my moms daily driver…All the Way From Cali to Des Moines this summer! So the reliability is Crucial! She is going Alone!

  5. I am working on tuning I was trying to get the IAC down below 10 Like the video recommends however I just realized a few things The Truck is not coming up to operating temperature. After 30 minutes sitting in the garage it is at 146 degrees according to the sniper Display and my own water gauge is a hair below 160 so I think its the 160 degree thermostat I installed? It was very cool this morning perhaps not allowing it to get to operating temp? I had previously used A 180 Hyper-tech thermostat when I had my Holley Carb but it would go past 210 degrees so I changed it while doing the EFI Upgrade. My thinking was I had a over heating problem caused by the thermostat. I noticed after 30 minutes The IAC just sits at 26
    Anyway someone told me the sniper and other EFI set ups like Warmer temp so please let me know what to select thermostat wise.
    Also Do I return the Curb Idle Screw back to where it was before I ever started it then place the vehicle in Drive with someone holding the Brake And then Adjust the Screw down Will that move the IAC Down?…

  6. I've read that you can install the sniper EFI on a supercharger, and that the only major hurdle is installing an external MAP sensor on the supercharger manifold. Where does the external MAP sensor plug into the throttle body? Would Holley #554-134 work on, say, a weiand 174 supercharger and manifold?

  7. Looking for your recommendation on a replacement intake manifold to use with your system. Old 3 deuce set up now.
    Motor is a 400 sbc with lumpy cam, spec U..K. Thanks

  8. Hello everything seems OK I got my registration/Insurance.
    I got the Idle sorted out for the most part I set it at 570 on the hand held it Purrs at that RPM
    There is another thing I have not figured out yet…
    The vehicle always Starts Hot or Cold At higher RPM between 1400 RPM & 1500 As if it was A Cold start however it Does the same after its warmed up takes about 10 seconds for it to settle down sort of embarrasing in the grocery store parking lot with my loud exhaust so how do I adjust that out of it? Or should A Local Holley Tuner do that.? I am OK doing MONKEY SEE MONKEY DO… But I have to hand it to the Tuners They know their stuff!


  9. Once again you guys and the Kit Saved me. I had the Bracket for the Trans reversed I could not get my 700R4 to shift properly so last night I went back and read the quick guide and there was the photo of the throttle bracket/Trans…Sure enough I had it backward facing not straight one on top of the other.. I have the timing right at 13.9 14.1 on the Display and right at the end of the Timing Tab ALMOST I still get that sound some confuse it for vacuum under full throttle Mashing it only if you stretch it out and work up to full throttle it makes no noise but it feels like it needs or wants another degree or 2 of Timing is that ok to do? this is A Roller 350 87/95 variety Self Aligning rockers 87/95 NON Vortec Heads…Had I known I would have got the Vortec Heads Live & Learn.

  10. only thing is,…it's not E-FIE. It's E,….F…..I. Godamn it sounds stupid when your video starts right off with someone who can't say each separate sound of the EFI.

  11. Where did you find the coolant bushing for the Coolant Temp Sensor? I bought the 2300 series 2barrel kit and am doing this to a 1971 chevelle with a 350 small block, I can't find a brass bushing like that. Also what size is it 3/4 x 3/8?

  12. This looks great but i have a question. If i swap out motors in 2 yrs, will the sniper efi adapt to the new motor?

  13. Can you run an in tank fuel pump as a helper to the Holley pump? Thanks
    Working on a 69' Camaro the guy just spent $700 on the tank then decided to go with the sniper setup..

  14. I noticed where you put the wire for the fuel pump. Did you just stick a stripped wire into the fuse block? How is the wire secured?

  15. My fuel tank had a drain plug, i used a brass threaded union that fit where the plug went for my return line

  16. Good video. He removes the spacer after removing the carb. Is it necessary? I have a similar setup and would like to keep the spacer. will there be a problem if I keep it?

  17. Well i can tell you the systems are not perfect none of them are i have installed 3 msd atomic no issues so far and 4 fitech's some issues but their customer service was bad. I am going to try this sniper on my 68 gto and see how it fairs against the others.

  18. Is it worth it to buy the master kit? Im looking at getting a sniper for my camaro but im on a bit of a budget, is it more economical to just buy the pump and other things in the master kit from my local parts store or do I save money getting the kit?

  19. I'm very interested in the Holley Sniper system for my 71 Pontiac Formula 400 Firebird. My car has functional ram air using a factory ram air air cleaner and there is very little hood clearance. Will my factory drop base air cleaner work with the Sniper?

  20. Just a note.  Holley no longer includes the mounting studs/nuts, air cleaner stud, throttle/transmission brackets,  throttle linkage studs, or zip ties/terminals.  Summit told me these are now sold separately.  A little disappointing since all of their advertisements show these.

  21. master kit is not complete like in the video lot of missing part like the stud and nut the air cleaner screw and the old gas pump hole blocker

  22. I have recently purchced the Holley EFI sniper master kit as it is sapose to have everything needed to install the complete system. Well, the kit is not complete and Holley said they no longer supply the EFI mounting studs, air cleaner studs, Fuel block off plate, throttle hook up linkage, electrical connectors and zip ties. So after spending over $1250 for the master kit, be prepaired to buy what ever else they left out of the kit. Also they don't put steel braided fuel line on the EFI like they use to. What a disapointment.

  23. Brought a Holley Sniper and installed it to a 350 chev motor. ( installed professionally) . Now ,after 6000 klm,you tune it but as soon as it gets to operating temperature it go back to factory settings.. NOT HAPPY WITH IT.

  24. MSD Atomic beats the Holly system hands down. And thats coming from a guy who has had holly carbs on all my street rods for 35 years. Its better priced. It makes more power. Its easier to install and hook up. It works better with their Ignition units/Distributers. They provide better tech support, and lastly, you can control your timing curve, and cooling fans with their EFI system. A whole MSD conversion kit for a old muscle car/street driver car is 1300 dollars. Holly is around 2000 for a whole conversion. IMHO I think MSD did it better. Sorry Holly.

  25. great kit, installing now but wish the master kits they send out now were as complete as this, no longer comes with brackets, carb studs or wiring connectors.

  26. I will never understand why on earth anyone would install an EFI without a return. Unless you really like to boil your fuel and overwork your pump, I see no reason to not.

  27. nice video, i was wondering if this system kit only work for American build cars, or would it work for my Mercedes Benz W123, 1983, 2000cc gasoline motor?

  28. Is there a brake boost vacuum port on the Sniper or would a pump need to be installed. I see a lot of videos of older cars have this installed but no one mentions it.

  29. just dont buy this shit worthless never been able to make it run properly not learning anything very hard on first start cost like 2000$ cad and now iam looking for a carb holley sniper is just a way to steal your money you will end up buying a carb anyway so dont be a guinea pig and holley dont respond to email and they dont give a shit after they got your money

  30. Just awesome. I will be doing this!
    I take it there's a way to set the ignition curve or is it just a linear increase with RPM/vacuum taken into account?
    Also, is there any reason one could not use the old metal fuel supply line for the RETURN line?

  31. Mine is a W133 200, which comes with a W102 gasoline engine, they are mostly available in Europe and Asia market, I don’t think they were available in the US, anyways, I did buy one 2 barrel already, waiting for shipping to arrive, my next concern is my intake flange sits sideways, I wonder if sniper EFI can sit 90 degrees sideways?or I need to have it converted upright? And where do you you suggest I can find an adapter for the intake manifold?

  32. Are these able to be 100% manually tunable? I know the self tuning aspect of this carb isn't able to work for rotaries, but would love to use this on my large street port NA 13B which I've been using a racing beat modified 465CFM 4 barrel on which is great, but I'd like to be able to fine tune and surpass the current 7,000 RPM redline (engine is being built to handle a 9,000 RPM reliably), so if the self tuning aspect can be disabled or simply not used at all, that would be perfect.

    *I also have my spare stock port 12A which is currently running in the car that I can use to test on so I'm not risking a freshly built engine

  33. update, after many many frustrating hours trying to get this system to work correctly(sniper and dual sync) i pulled everything off and reinstalled a carb and hei distributor. seems like a great product but wasnt as plug and play as i thought it was going to be.

  34. I'm considering installing one of these on a V8 Falcon (302 Windsor) Australian vehicle which already has EFI from the factory but the inlet manifold and throttle body sucks. Are the kits any different for a system already EFI from the factory?

  35. i have a 93 suburban that i did the carb conversion from the EFI set up it runs good but still all the drawbacks of a carb …wish i had seen this video back in april i plan to get the engine rebuilt or get a crate engine i would really like to go back to EFI

  36. I noticed you specifically said to "NOT" hook up the ground wire, yet then while searching for a switch 12v source, you crank the motor? Not possible if ground not hooked up. Now, if you meant it was ok to hook up the main ground to the battery, just not the wiring harness ground, I'll give you a pass.

  37. Why doesn't Holley include everything in this video in the kit anymore? It's disappointing that I have to still buy extra parts after buying the "kit"

  38. What is the reason the positive and negative can't go to a engine fuse box? They don't look like they're high amp wires, and I can't think of any reason electrically to do this.

  39. Man, this is a brilliant kit. I'll have to wait till I have some more money to blow. I was thinking the O2 sensor would be a pain but they've thought it all out. Only problem I have is I have true duals from the manifolds back

  40. Doesn't come with mounting studs, connectors or cable brackets. Just bought one and only came with half whats shown here.

  41. Shouldn't there be two O2 sensors on a dual exhaust set up? Seems like it would cause an issue only reading one bank.

  42. I had a Holley Sniper installed in my '55 Nomad with a crate 350. Seems great. But in the extreme hot weather, Phoenix, the car stalled and I had to wait 15 minutes or so to restart it and go. Don't know if the fuel is boiling or what???? If any one has a suggestion, please let me know. Thanks

  43. Hello Sir, I am installing the Terminator EFI on my 1970 Dodge Challenger 440 with headers-There is no room to conveniently mount the fuel pressure regulator on the fire wall along with the CPU-Please demonstrate a plug & play installation for the Big Block guys, It's annoying how easy it is to install on a small block!

  44. As someone who has installed numerous FAST EFI systems, the Holley Sniper systems blow the FAST systems away in every category.

  45. I like how they say, "how easy it is to install". Plug and play my ass. They should let everyone know every installation is different.

  46. thats all good but like me your system dont work for a 76 camaro LT with a 305 5.0 so what do i do to have the same shit

  47. Is LS better than SBC when carberated? Could a stock 4.8/5.3 LSX produce more horsepower/torque than a stock SBC 350 carbureted?

  48. A fantastic setup
    More power and torque through the curve.
    As well as better starting and you and jt can tune for for fuels like E85.

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