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2016 R/T
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191 Posts
Discussion Starter #1
Finally pulled together the parts and time, and upgraded my R/T’s intake to the active runner intake manifold; AKA the 392 intake manifold swap. I had a few issues crop up that I had to deal with and ended up implementing a fairly unique variation on the build, so I thought I’d share here. I’ve provided photos of the finished product in Attachments 1 and 2.

I’ll start by giving credit to this post (6.4 intake manifold on 5.7) which gave me all of the information I needed to take this on. I ended up implementing my build a little differently, so I’ll give my experience in this post.

Hardware required for my implementation:
*** A note on the intake manifold part number. I took this part number from the above referenced post, but I actually purchased a different part number by mistake. I don’t want to spread confusion so I won’t cite my specific part number, as what I got did not come with the mass air flow sensor, PCV valve, the active runner actuator, and the bolts that connect the actuator to the manifold. That was a costly mistake as the individual component costs add up quickly, so I strongly encourage you to double check your part number prior to purchase to make sure Google doesn’t pull up a “similar” match for you.

Tools and consumables required for my implementation:
  • Two rolls of 3M Acetate tape, Mouser part number 517-11-1/4"X72YDS
  • Liquid electrical tape
  • Solder and soldering iron
  • Heat gun
  • Heat shrink wrap
  • Wire strippers
  • Sharp exacto knife
  • Torque wrench sensitive at 108 in·lbs
  • Wrenches, screwdrivers, typical tools
  • O-ring lubricant (I lubricated every o-ring upon install/reinstall)
  • Dremel with disc bit
  • Hacksaw blade
  • Coarse sandpaper
  • Black silicone gasket maker
I decided to start and end my build with the wiring harness. I’ve included a schematic diagram of my wiring in Attachment 3. The box labeled “12 V supply tied to car’s ON/OFF” is where the output of a Cirkit Boss would be in the typical build instructions commonly circulated on the website. However you’ve probably noticed that the Cirkit Boss is not in my parts list, and that’s because I’ve opted to eliminate the Cirkit Boss in my build.

The Cirkit Boss does two things; first it provides the equipment with 12 V only when the car is on, and second it provides a fused circuit external to your factory fuse box. I browsed my owner’s manual to identify a circuit that the Cirkit Boss could use to identify when the car is on or off (the Cirkit Boss’s pink wire), and decided to use fuse circuit number 38 with a 10 A circuit for optional equipment my car does not have. I plugged the Add-a-circuit fuse tap here, retaining the original 10 A fuse and adding a 10 A fuse to supply my new circuit. This seems to be sufficient to power the system’s MSD and active runner actuator, allowing me to phase the Cirkit Boss out of the design.

Now back to the circuit diagram in Attachment 3. The MSD box is shown at the bottom, with its white, yellow, black, and red wires. Its gray wire is unused. The white line goes to a fuel injector to provide the MSD with the car’s RPM. Yellow is the switching signal; when the engine hits the MSD’s programmed switching RPM then the signal on yellow will flip to tell the active runners to engage/disengage. Black and red are ground and 12 V respectively, which is required at both the MSD and the connector to the active runners.

Now before you actually start the wiring, don’t forget to disconnect the battery. And before you disconnect the battery, don’t forget to roll your windows down a little so they don’t yank on the weatherstripping when you open the door with no power. Some of my wiring can be seen in the attached photographs.
  • All right so here is my trick for the wiring. The problem is that if you don’t know precisely where you’re going to place your MSD box, you can’t really install your actuator connector plug or tap into the fuel injector as you won’t know how much extra wire needs to be cut off. What I decided to do is cut all five wires coming out of the MSD box about 8 inches from the box. I’ll reconnect them with the generic automotive connector at the end of the wiring harness build when all of the wiring is laid out in its final position.
  • Attachment 4 shows my connection to the fuel injector. This is the MSD boxes white wire, but you’re seeing purple in the photo because I needed a little more length on my white wire and had purple on hand. Cutting the insulation off of the fuel injector wire was stressful, but ended up being easier than expected. I used the wire strippers to cut around the circumference of the insulation at two points, and then the sharp exacto knife to cut the length between those two cuts. I connected the wires using the connection/soldering technique I saw here;
    . After soldering, I applied several coats of liquid electrical tape, then once dry a little super 33 electrical tape for good measure followed by the 3M acetate tape all the way along the wire for physical protection.
  • Attachment 5 shows my connector that plugs into the active runner actuator. This connector comes with the pins crimped onto orange wires, so I just attached my MSD’s red, black, and yellow onto the appropriate ends. The connector has four sockets. If the connector is sitting in front of you such that the red locking clip is facing up and you're looking into the socket receptacles, you'll install red, black, yellow into sockets 1, 2, and 3 as seen in the photo. Pin 4 is unused. My wire interconnects are soldered and protected by two layers of heat shrink wrap, then 3M acetate tape along the full length of the wire. In addition, each splice/solder point is staggered lengthwise so that the solder connections are never in the same location between wires.
  • The injector wire and actuator plug are back behind the intake manifold. I bound them all together with the 3M acetate tape and ran them back towards the fuse box. Instead of terminating directly at the MSD box, all four wires terminate in the generic automotive connector as seen in Attachment 6. This makes it easier to ensure all of the wires have the same length when they arrive back at the fuse box, and gives a really nice clean look at the MSD box.
  • Attachment 6 also shows where I teed off lines from the red and black wires to tap into power and ground. I used the same splicing/soldering technique as on the fuel injector interconnect, and again the tee-off locations are staggered lengthwise down the wire so the two connection/solder points are not in the same location along the wires. The black wire ties into any of the car’s grounding sites. The red wire goes up to my fuse box, where it mates into the Add-a-circuit fuse tap which comes with crimp-on connectors.
  • Once all of the wiring is laid and covered in 3M acetate tape, I pushed most of it into the wire conduit tubing for added protection and a clean look. Now all that remains are my red/black/yellow/white wires all bound together near the fuse box. I can now place my MSD box, cut all of the excess wire to length, and connect them using the generic automotive connector plugs.
Now for the actual manifold swap. You’ll need to disconnect your throttle body and its electrical connector, air inlet tube and the intake air temperature sensor on it, all 8 fuel injector plugs, oil catch can (if applicable), the fuel line connection (open gas cap first to relieve pressure, disconnect with rag around tube to catch fuel in line), the tube under the oil fill that connects to the airbox, the vacuum tube at the front of the intake manifold, and the mass air flow sensor plug on the backside of the manifold. There’s also a rubber hose deep behind the intake manifold that needs to be unplugged, but won’t be reachable until you can pull the manifold forward a short distance.

There are a total of ten bolts holding the manifold on the engine. Attachment 7 shows the bolt tightening order, so just follow this in reverse for removal. I opt to loosen them a little at a time so no side is ever attached at full torque while the other side is loose. Once the bolts are removed the manifold can be lifted and pulled forward until you can reach the rubber hose on its lower backside and disconnect it. It was a tough pull, but it just pulls out with some pulling and twisting.

With the old intake manifold out, its fuel rails can be removed by unscrewing the four engine cover posts that secure them. I added o-ring lubricant to the fuel injector’s o-rings prior to reinstalling them into the new intake manifold. I don’t know the torque spec on these four bolts, but they thread into the manifold so I was careful not to tighten them particularly hard. The fuel rail isn’t going anywhere.

Before putting the new manifold on, you’ll need to extend the mass air flow sensor wiring to reach the new connection location. I used some leftover wire from the actuator connector plug kit to extend this wiring, again staggering the three splice locations lengthwise along the wire. The solder points are protected with heat shrink wrap, and then the new longer wiring section is covered in 3M acetate tape for protection.

Now the new manifold can be installed. First make sure all loose wires and tubes are out of the way so they don’t end up under the manifold when you place it. As you move it into position, you’ll need to plug that hard-to-reach hose on the backside before setting it into its final position. Once in place, make sure all of your connectors are present and accounted for, but don’t bother plugging them in yet as some of them can interfere with access to the intake manifold bolts. The tightening order is shown in attachment 7. The bolts are to be tightened to 108 in·lbs, and again I opt to tighten them incrementally up to that final setpoint so no side is ever at full torque while another side is loose.

Once all ten bolts are at their torque setpoint, go ahead and plug all of the connections back in, reinstall the throttle body, and the new air inlet tube section. You’ll find that the air temperature sensor is too short, so you’ll need to extend it just as was done on the mass air flow sensor wiring. I decided to run mine through wire loom over the top of the intake manifold, to parallel the look of the fuel delivery tube that runs the same path further down the intake manifold.

And now finally the last component, connection to the MSD box. As for the MSD box location, I decided to mount it in the MOPAR ABS brake system cover as seen in Attachment 8. After extremely careful measurement and taping off the surfaces, I cut the window. I used a Dremel with a cutting disc to make the initial cut, then fed the hacksaw blade through the opening and used the hacksaw blade to make a clean line. I erred on the side of caution, and ended up having to do a lot of sanding to open the window up enough to fit the MSD box in. Eventually I got there, at which point I mounted the MSD in the window and used black silicone gasket along the backside window perimeter to secure the box. Now I have my MSD box mounted in the ABS cover, protruding just above the surface to ensure that water cannot pool.

And that’s it. No check engine lights and the MSD box is on and sensing the engine RPM so everything appears to be working. I’m a bit concerned that the black silicone gasket may not have been the best material to secure the MSD box in the window I made for it, but its at least rated for high temperature so we’ll see how it holds over time. I’ll update the thread if I learn anything as time goes on.

Finished - left-side view.jpg
Finished - right-side view.jpg
Circuit diagram.jpg
Injector splice wire wrap.jpg
Actuator connector.jpg
End of wiring harness - labeled.jpg
Bolt pattern.jpg
MSD box.jpg
 

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Thats friggin slick! Clean install make sure you tell your tuner what RPM you set the valves too, my tuner was chasing the random power spike at 4600 for like 30 minutes lol
 

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2016 R/T
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Discussion Starter #3
Thats friggin slick! Clean install make sure you tell your tuner what RPM you set the valves too, my tuner was chasing the random power spike at 4600 for like 30 minutes lol
Haha that's really funny, I definitely would not have thought of that! I'm hoping maybe I can do shorty headers in the near future, and just do one tuning session to dial them both in together. I know that long tubes are known to be superior, but I've thought about it a long time and I just don't want to play games with emissions laws. In the much more distant future, I'd love to get a more aggressive cam shaft as well. I can't even imagine what all that would buy me, but I certainly have calculated the price and its clear that its gonna be a while.

In the more immediate future, I'm trying to think of something to do in the spare space in the ABS cover below my MSD box window. I'm thinking about putting some kind of bee artwork.
 

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Haha that's really funny, I definitely would not have thought of that! I'm hoping maybe I can do shorty headers in the near future, and just do one tuning session to dial them both in together. I know that long tubes are known to be superior, but I've thought about it a long time and I just don't want to play games with emissions laws. In the much more distant future, I'd love to get a more aggressive cam shaft as well. I can't even imagine what all that would buy me, but I certainly have calculated the price and its clear that its gonna be a while.

In the more immediate future, I'm trying to think of something to do in the spare space in the ABS cover below my MSD box window. I'm thinking about putting some kind of bee artwork.
With this manifold and hellcat shorties (and high flow cats-catback) my tuner got it up to 350/420

So it should be good with the headers

Yeah its nuts you really have no indication the valves are working until you see the dyno spike haha

994945


Gives you an idea how the 5.7 cam makes power, after the dyno run he recommended i drop it to 4400 since power drops off earlier then the 6.4 cam that its built for
 
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