I finished installing the Holley Sniper on my AMC 360 this weekend and wanted to do a detailed write up on the install for anyone thinking about buying this set up.
The most time consuming part of the install was modifying the fuel system so lets start there. I decided to go with the master kit with the inline fuel pump. First thing I did was modify the Fuel Sending unit. This is going into a 77 J10 so your fuel system might be different. I have a MTS Poly tank and a single sending unit.
First thing I did was drop the tank and pull the Sending unit. I cut out both return and main tubes. I then Drilled out the 5/16 main line hole to fit 3/8 fuel/brake line. I tapped the 1/4 inch hole to fit a set screw and installed fuel proof sealant and a set screw to block that hole. I then made the close to 90 degree bend on the new 3/8 fuel line and soldered it into the old main line hole that was drilled out to fit the bigger tube. After soldering it I bent the bottom of the tube to fit the old fuel line angle so everything was exactly the same. Then using this fitting: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
I was able to attach the holley supplied an-6 fitting on the new line.
The Holley supplied return line bulk head fitting was not going to fit on the fuel sending unit but I was able to put it in the relief hole for the sending unit. Install was easy just had to get creative with a wrench to tighten everything down. Make sure if you are going to drill into your tank you get all the gas out and fill the tank with water. I was less concerned with spark (although it can still happen) because my tank was plastic so I felt comfortable going this route. One trick to help reduce clean up when drilling the hole: I was holding a small cup on the back side of the hole catching all the drilling debris so I did not leave any debris in the tank.
Pump mounting bracket
I decided to run my pump attached to a bracket that I attached to the fuel tank straps. Originally the plan was to have pre filter, pump, and post filter on this bracket but after getting the tank back in the space was too tight. So pre filter and pump stayed on the bracket and I moved the post filter to the frame rail (with self adhesive foam behind it to help with frame vibrations). This set up worked perfectly and allowed me to run the hoses in large sweeping bends as to not strain the fuel line. The lines were run through the cross member holes and onto the frame rails.
*side note many people have had issues with the MTS tanks not fitting well with the original straps. To solve this I cut a commercial rubber floor mat and installed it with carpet tape on the bed tank support cross members and on top of the tank in those same locations (rubber on rubber). This made the tank so much tighter. I originally put this on the straps as well but it was too much added thickness to get the straps on the studs to tighten them down:
Exhaust 02 bung Install
This took me a bit of time as the space to drill the hole for the bung was pretty tight. I wanted to be off the passenger side bank. To get a space flat enough and with enough space to drill I ended up dropping the exhaust. Be careful when you tight down the clamps if you tighten them to fast they can get torqued and not want to tighten further. Don't ask me how I know
. Ended up having to use a stainless band clamp on one side.
Wiring was super easy. I am currently running an MSD Distributor but am not running timing control right now. I wanted to get the system up and running before messing with timing control.
wire goes to negative side of coil.
goes to positive side of battery
goes to negative side of battery
this is the one that trips everyone up. I used a weather pack connector to connect to the old red with trace fire that powered the old distributor. It had 12v with cranking and ignition on.
The only wire I used on the 10 wire harness was the brown
which went to the tach. I also kept the white
wire on because I will use that when I do do timing control. I removed all other wires and plugged the holes with weather pack hole plugs.
Easily fit into the front coolant passage on the Edelbrock 2131.
Was able to use my existing throttle cable with the Holley supplied bracket.
Hand Held Touch Screen
Mounted it in the cab with a self adhesive mount.
PCV Connected into the back large vacuum connection. Brake booster moved to a fitting on the manifold intake.
I flushed the fuel by not connecting the main line to the sniper before start up and cycling the ignition a couple of times. This pumped the fuel into a spare container flushing any potential debri into a the container and not the sniper. Then I hooked up the fuel line to an inline fuel pressure gauge and into the the sniper to verify I had 58 psi, which I did. So I was good to start this thing
Start up was easy. Make sure you follow the start up wizard directions and after going through everything hit the start button on the screen which will download the tune. Cycle the ignition and you should be ready to go. Fuel pump should kick on, you need to wait a couple seconds so the fuel pump can prime then turn the key. My engine started right up. Idle was a little high but after warming up the engine I was able to adjust the idle speed screw to lower the idle to my desired 800 rpm and the IAC in the correct position.
I think most people should be able to do this is in a day. So far I love this thing. I was really struggling with my carb ( I am a carb noob) the sniper fixed all of my issues. My truck idles great and the driving has been so much better than before. Its responsive and so far has handled everything I have thrown at it. It starts right up every time, no pumping the gas pedal, turn the key and you are good to go. I cannot suggest this system enough.
Let me know if you guys have any questions. I hope this is helpful.