DIY Breather Systems from AC Performance

[ViperTony]

The reason I created this thread is to detail a DIY for installing AC Performance's Breather system, the reasons why I selected Todd's system, my specific needs, etc. in hopes that it will help members make an informed decision should they decide to undertake this modification. These DIY's are time consuming and the write ups take longer than actually installing this system. I don't mind taking the time to help members that are genuinely interested in these topics but if folks want to stir the pot bashing "quality" and price then you all can kiss my ass and I'll keep the write-up for myself. It's your call. If you have something of value to add to this DIY, post it.

Part I

History

Whether or not one requires a catch can, breather system, air/oil separator or "puke tanks" depends on each Viper's situation and needs. With forced induction and larger NA builds catch cans are almost always must. With increased compression, higher boost levels blow-by can increase causing oil and oil vapors making their way into the intake system degrading fuel octane, possible detonation issues, etc. Some Viper engines have more blow-by then others. This breather system is overkill on a stock Viper engine. In my particular case, I became concerned about this topic when I removed my intake a few years ago in order to install a lower temp t-stat. At the time, I found oil in the intake runners and it peaked my interest. As I researching and consulted with folks on the matter I began to learn more about the PCV/CCV system particularly on my '01 Viper. Considering that, at the time, the oil found was "normal" and I wasn't boosting and had a relatively stock motor, I let it go. Last year, however, when I underwent my Creampuff build with Greg Good goodies I found that my intake was disgustingly caked with grime and oil residue. So much so that the wash tank at my powder coater turned pitch black from the cleaning process. It was at that time that I wanted to trace the problem or at the very least make an improvement in the system. I traced the source of oil from my Crank Case ventilation or "CCV Orifice" atop of the engine block. This connection contains a metered fitting that ties into the intake. So I installed a CCV Air/Oil Seperator. It worked very well and I captured 2-3oz of oil between oil changes. On my last tracking outing at NJMP, I caught 6oz of oil after 8 track sessions over two days. It did it's job well but after removing the intake I still found traces of oil in the intake runners although it was much less then before.

My goal was/is to completely catch any oil from making it's way into the intake and for this to occur I decided I needed to catch the valve covers as well. Before installing another can I did some research and was led to Todd @ AC Performance. Todd had already proved himself to me by tuning my Viper, exceptional customer service and earned more business from me. His breather system has everything I was looking for and met the following requirements:

• Eliminates the need for the CCV hookup to the intake
• Catches oil from the optimal location on the top of the valve covers
• Uses one tank
• Well thought out and proven based on customer feedback/experience
• Doesn't look like a jury-rigged hillbilly system
• Can be modified
• Complete package/High Quality

Diagnostics

Before jumping into a breather, I decided to perform a compression and leak-down test. The purpose of these tests was to determine if my engine had more serious issues with blow by, valve seals, leaks, etc. If these problems persisted a breather system was not going to solve much of anything. With a warm engine, my compression readings ranged from 192 - 200psi with one cylinder reading 186psi. The leakdown test showed an average difference of 4% between cylinders. Satisfied my engine was healthy I moved on to the breather system.

The Completed Install

BreatherInstallFinished.jpg

The AC Performance breather system installs proprietary fittings on top of each valve cover as can be seen above. Yes, if you decide to install this system you will need to drill into your valve covers. If this makes you squeemish, stop here and don't read on as Part II of the write up will get into the gory details of drilling valve covers.

The hose from the driver's side valve cover snakes it's way under the throttle bodies to the passenger side connection. As will be shown in PartII, I capped my CCV connection and eliminated the CCV to Intake connection. The hose from the driver's side fits in nicely and almost disappears under the TB's.

BreatherTBs.jpg

On the passenger side, both hoses (Passenger/Driver Valve Covers) come together to what I call a junction point using fittings supplied in the package. I should mention that all hoses are measured and come assembled with fittings cut to length. There's no need to cut or splice anything with this system:

JunctionPoint.jpg

Bling Alert: I know that for a very long time I never hesitated to mock someone's white hood vents and shiny things in an engine bay that serve no purpose other than "bling" effect would cause me aneurysms. However, I can mock these folks no more because I now have a very beautiful piece of art in engine bay, Todd's custom, baffled and polished catch tank:

BreatherTankKN.jpg

Here's another view of the tank without the breather and lines tucked away neatly:

DSC066991.JPG

[ViperTony]

Part I Continued:

It's worth nothing that the K&N Breather on the tank is not part of the system or design. In fact, Todd supplies a hose that connects to the breather location in the pic and runs to the airbox with the idea being the tank vents into the airbox and not to the atmosphere. This is the actual hose used to connect into the airbox from the tank:

HoseAirbox.jpg

It's long enough to reach the driver's side of the airbox. Fittings are included to help make the connection to the airbox but more on that in Part III.

Regarding the catch tank, it's designed to fit the wheel well area and utilizes an existing bolt location on the blower motor and requires drilling a small hole to bolt into the wheel well cover.

Part II Valve Cover Removal/Drilling

If it isn't obvious by now, both valve covers will have to be removed in order to install the adapters. Before removing the valve covers, you may want to take a few precautionary steps to prevent your valve cover paint from getting chipped/dinged:

• Use blue painters tape and tape up as much of the valve cover as you can.
• Remove any obstructions that will get in the way of removing the valve covers.
• Disconnect (optional) the vacuum hose between the intake and brake cylinder on the driver's side.

I used a T27 torx bit, my screwdriver and a drill to remove the 13 bolts holding down the valve cover. Be careful working the bolt under the MAP sensor (Driver's side rear). If it's in the way, remove it. I don't use heat shields which is why you don't see them in the pics. Removing the heat shields is not required. Below is the driver's side VC showing the bolt location.

DrVCRemoval.jpg

After removing the bolts from the VC, you may want to place some shop towels between the top of the heat shield/headers and bottom of the VC to collect any possible oil that may work it's down after lifting the VC. Carefully lift and remove the valve cover.

Driver's Side Valve Cover removed:

VCRemoved.jpg

The valve cover gasket is durable and reusable. Remove it and wipe off any oil along the head area. Note that I did not remove the spark plug holder bolts on the driver's side valve cover as they were not in the way, for me.

On the Passenger side valve cover, I did remove the spark plug holder bolt that also mounts the coolant line bracket using a 7/16" ratcheting wrench:

PassVCRemoval1.jpg

Also remove the bolt holding the dipstick bracket to the valve cover:

PassVCRemoval2.jpg

* Note: The passenger-side VC (at least for me) is wedged between the coolant hoses snaking in the rear and front of the VC. Use caution when removing the VC to avoid scraping your VC paint in this area.

[ViperTony]

Part II Continued:

Valve Cover Baffle Removal

Once the valve covers are removed, you'll need to remove the internal baffles. The baffle is held in place with machine screws and sealed with black gasket maker/sealer. I ran my exacto knife through the gasket to facilitate easier remove of the baffle. Using my drill, I unscrewed the sheet metal screws:

VC_Baffle_Removal_1.jpg

With the screws removed, carefully lift/pry the baffle from the valve cover. If it's sticking near the black sealant, use your exacto knife to cut it away. Be careful not to crack this baffle during removal.

Baffle removed:

VC_Baffle_Removed.jpg

Side Note: You may be wondering why I have copper sealant in mine. I removed my baffles some time ago when I installed my T&D rockers. I need to raise the baffles to clear the rockers. I did this by grinding down the mounting points about 1/4" and reinstalled the baffle using Copper RTV at the time.

At this point, you can choose to scrape off the gasket residue both from the baffle and valve cover. I did this step later, it's up to you. I recommend removing this material and thoroughly cleaning the inside of the valve cover before installing the baffle and applying a new bead of sealant.

Flipping the valve cover over, we need to orient the supplied metal template and drill some holes. The template needs to be oriented over the "IPE" part of "Viper" on the VC:

TemplatePositioning.jpg

Proper orientation is important as you'll see later. With the template centered over the "IPE" area, I marked the holes with a Sharpie. I then remove the template and drilled two pilot holes to get started:

MarkedHoles.jpg

Drilled out the 1/2" holes:

DrilledHoles.jpg

[ViperTony]

For the 4 smaller holes, I drilled a couple and used the supplied screws to keep the template in place to drill the remaining holes. These 4 are important to line up perfectly with the adapter.

TemplateHoldDown.jpg

With the holes drilled it's time to mount the adapter/fitting on top of the valve cover. These come assembled with the AN connector and rubber gasket. Make certain that the orientation of the fitting is such that the AN connection is point towards the front of the engine. Using the supplied red Loctite, install and tighten down the screws from the inside of the valve cover:

VCAdapterUnderside1.jpg

Looking from the inside the VC, you can see where the two large holes end up on either side of the mounting stud, which is why it's important to line up the template properly.

VCAdapterMounted.jpg

Same procedure for the passenger side valve cover. At this point, I cleaned up the valve covers, removed gasket material, metal shavings, gave it good cleaning to make certain no debris or gasket material was left behind. I reinstalled the baffles using the machine screws and red loctite. I then ran a bead of RTV Black Gasket sealer around the baffle.

Reinstall the valve covers.

Next part is installing the supplied breather lines and tank.

[ViperTony]

Part III: Hose Removal/Capping Ports

This is a fairly easy part of the process. We're moving on to remove the stock CCV Hose-To-Intake connection and the stock Valve Cover-To-Airbox connections. Essentially, we're removing these items:

HosesToBeRemoved.jpg

The valve cover hose assembly can be simply pulled off from the Valve cover ports as my clamps weren't doing a great job holding them on. Save the clamps as you'll use them later. As for the removing the connection from the air box to the VC hose, simply pull it off of the airbox.

Regarding the CCV connection above, be careful with this one. In the picture above, namely the "CCV Hoses", the lower hose in the picture connects to the CCV orifice on top of the block just behind the T-stat (GenII). It connects to a plastic barbed fitting. When disconnecting the "Tee" portion of the hose DO NOT PULL ON THE HOSE WITH EXCESSIVE FORCE. Why? Because you can inadvertently pull out the plastic barb fitting on top of the block. Putting this fitting into the block with the intake bolted on is next to impossible.

Which begs the question: Do I need to remove the entire CCV hose assembly above or just the upper half that tees into the intake? You can do either. I chose to remove the entire assembly and cap the CCV orifice. It's much easier to remove the upper portion of the CCV hose assembly and simply cap the hose that connects to the CCV barb fitting.

Essentially, I'm talking about this and is optional and not required for the AC system installation.
HosesCCVRemove.jpg

Sorry for the poor picture but the area is difficult to get a good shot. I think I have more pics of this area from my CCV write up. I decided to go the difficult way and cap off the CCV on top of the block. This was a painful task to accomplish with the intake bolted on but it can be done. Since I could not get any good pics of this process, I used this TEE as an example:

TeeCCVCap.jpg

I used a vacuum plug boot on the CCV barb and use a hose clamp to lock it on. No chance of it coming off. Again, YOU DON'T HAVE TO PERFORM THIS STEP! Simply plug the lower half of the CCV hose assembly. You're knuckles will thank you.


I used these hose clamps on the CCV Barb/Cap area. I found them at my local hardware store, no idea what the part numbers are:

ClampRTV.jpg

With the CCV capped off, we can now cap off the intake ports and VC ports since they will no longer be used. Todd supplies various-sized pipe-plug fittings for this. This entail removing the slip-on ports, drilling/tapping for the pipe plugs and then screwing them on. Todd doesn't like to see rubbers throughout his engines and prefers the pipe-plug approach. Truth be told, I felt too lazy to install the pipe plugs. I will most likely do this over the winter. Instead, I used simple Vacuum caps I found at AdvanceAuto. Namely, I purchased two of these packages:


VacuumCaps.jpg

[ViperTony]

Part III Continued:

Intake ports capped off:
IntakePortsCapped.jpg

Valve Cover ports capped off and reusing stock clamps to help secure them. Todd does supply screw in plugs used to cap off the valve covers but I chose this instead:

VCPortsCapped.jpg

The last port to cap off is the airbox connection (Optional). Remember, I chose to vent my catch tank to the atmosphere even though Todd supplies the hose and fittings to connect back into the airbox. I used a 3/8" diameter vacuum cap:

AirboxCapped.jpg

[ViperTony]

Part IV: Final Assembly

The last portion of the breather system installation is fairly easy. This consists of installing the breather tank and running/hooking up the braided lines. The custom tank is installed on the passenger-side fender well area:

TankMounting.jpg

The tank is mounted with two bolts. It uses the existing bolt location that mounts your airbox to the fan motor. It also required that a hole be drilled into the wheel-well cover in order to secure it:

TankMountedBolt.jpg

Once the tank is installed, it's just a matter of hooking up the supplied lines per the installation instructions.

Note about securing the lines/fittings.

- All of the lines include the various AN fittings pre-installed
- The AN fittings can scratch easily so be certain to use an appropriate AN wrench OR tape your wrenches with blue painters tape in order to prevent scratching.
- Don't over-torque these fittings!
- The lines are long enough so that they can be snaked along and concealed as much as possible.
- When snaking the lines, particularly under the throttle bodies, you may want to tape up the AN end fittings so they don't become scratched during the process.

There's no particular order for the line installation but I:

- Installed the driver's side line, ran it to the junction point location below.
- Installed the passenger's side line, ran it to the junction point location.
- Installed the Tee fitting at the junction point.
- Ran a hose from the junction point to the Breather Tank "Input" side (first hose location near the blower motor).
- Ran a hose from the breather tank "Send" side to the airbox.
- Tightened all fittings.

Junction Location

JunctionPoint.jpg

Hoses Running Under TB's
These were zip tied for extra measure.
HosesTB.jpg

Airbox Hookup:

I decided to demonstrate how this hooks up to the airbox so I went ahead and drilled the Airbox to accommodate the 10AN fitting. If you recall, I started out the DIY with a breather element on the tank and no return to the airbox. Still not certain which one I prefer but here ya' go:

HoseToAirbox.jpg

I did this installation in a single afternoon, about 3hrs and could've done it quicker but I was being careful. I think Todd supplies a high-quality product and the instructions were easy to follow.

[Dan Cragin]

Great Post. What makes this system work so well is the manifolds that go on top of the valve covers. It allows you to run the larger 3/4 hoses needed to vent the crankcase properly, we use this type of system, vented to atmosphere on our race cars.

Good job Tony and A&C crew.

[ViperPete]

Great, detailed writeup!

[Goatman]

This is an awesome write up. Another mod added to the future list