Tech: 2015 Mustang Oil Separator

Photo of author

Tech: 2015 Mustang Oil Separator

Keep it Separated

Installing a Bob’s Auto Sports oil separator on a new Mustang GT

By Steve Turner

Your new Mustang’s positive crankshaft ventilation system’s top priority is improved emissions output, not maximum performance. As such, returning the unburned vapors from the crankcase to the intake to be burned again is its mission. An unfortunate side effect is that oil in this vapor from blow-by can contaminate the intake air.

Bob’s Auto Sports offers its oil separator in a variety of finishes, including bare aluminum, powdercoated colors, and hydrographic finishes.
Bob’s Auto Sports offers its oil separator in a variety of finishes, including bare aluminum, powdercoated colors, and hydrographic finishes.

Its main downside is that oil in the re-circulated vapor can actually diminish fuel octane, which can lead to detonation. As we know, the effect of detonation is, at best, decreased performance. At worst, detonation can lead to costly damage. If you own a supercharged Mustang with an intercooler in the inlet path, blow by can also clog it up and reduce its efficiency.

The hose from the passenger-side cam cover to the intake is the primary culprit in transferring oil contamination to the induction. A simple, but effective solution to this issue is to install an oil separator, or catch can, in the hoses between the cam covers and the intake system. Bob’s Auto Sports in Tampa, Florida, created on especially for the 2015 Mustang GT. The company designed its own unit for earlier Mustangs several years ago because it saw a need for a better mousetrap.

The Bob’s oil separator catch cans start out as single pieces of round aluminum bar stock.
The Bob’s oil separator catch cans start out as single pieces of round aluminum bar stock.

“At the time, nothing on the market was more than a cosmetic piece,” Steven Pellini of Bob’s Auto Sports said. “We are an engineering and manufacturing company so we have the means of building and testing multiple prototypes in house versus the others that are just outsourcing. This benefit helped us greatly with making an incredibly functional unit.”

The Bob Auto Sports oil separator is available in two configurations, Standard and Ultimate. The standard system sells for $114.95. It includes powdercoated brass fittings, rubber Eaton hoses, and stainless, worm-drive hose clamps.

Turning that aluminum billet into a separator are the CNC machines at Bob’s Auto Sports. All their parts are machined and built right here in the USA.
Turning that aluminum billet into a separator are the CNC machines at Bob’s Auto Sports. All their parts are machined and built right here in the USA.

“The size of the canister, size of the hoses, length of the hoses, all of those contribute to slowing the air down and letting it filter better. Also, our patented bottom-to-top-flow filter design keeps the oil further away from the outlet than any of our competition. Keeping the oil trapped in the media in the bottom is a huge benefit as when you have engine torque, potholes, speed bumps, loose oil in other units can bounce around and hit the unprotected outlet hole. We also offer multiple color options, hose/fitting options. It is much more custom unit than what else is on the market, and it features a drain valve on bottom, so you never need to remove the unit from your car.”

Installing a Bob’s Auto Sports oil separator is simple enough for even an auto writer. Get started by popping off the engine cover. You can sneak it out under the strut-tower brace if your car is so equipped. Then you can remove the factory breather hose.
Installing a Bob’s Auto Sports oil separator is simple enough for even an auto writer. Get started by popping off the engine cover. You can sneak it out under the strut-tower brace if your car is so equipped. Then you can remove the factory breather hose.

For another $85 you can step up the Ultimate system shown in our photos. This system upgrades you to aluminum AN fittings, Russell Pro Classic hoses, and Gates heat-shrink clamps. If you want the hydrocarbon finish shown here, that will tack on another $25, but you have to admit it looks great this way.

If you are familiar with the Bobs unit for the prior Mustangs, you’ll note this one is pretty similar. “We only had to redesign our brackets, and tweak the fittings angles and hose lengths,” Steven explained. “It was pretty painless.”

He walked us through the install process, which was painless as well, and if you keep reading all the way to the bottom, we will show you the hydrographic process, which is pretty cool.

The Bob’s Ultimate separator comes assembled with the hoses in place, but you do need to swap over the factory connector for the cam cover and intake fittings. Simply use a box cutter to slice the stock hose enough to free the factory connector. The Bob’s kit provides a heat-shrink clamp to hold the factory connectors in the new hoses.
The Bob’s Ultimate separator comes assembled with the hoses in place, but you do need to swap over the factory connector for the cam cover and intake fittings. Simply use a box cutter to slice the stock hose enough to free the factory connector. The Bob’s kit provides a heat-shrink clamp to hold the factory connectors in the new hoses.
Slide the heat-shrink clamp over the hose, push the barbed fitting of the factory connector into the new hose and turn it to the proper angle to mate with factory nipples. Then you are ready to turn on the heat gun and clamp the connector in place.
Slide the heat-shrink clamp over the hose, push the barbed fitting of the factory connector into the new hose and turn it to the proper angle to mate with factory nipples. Then you are ready to turn on the heat gun and clamp the connector in place.
The kit includes a bracket that installs using this factory fastener on the shock tower. Simply remove the bolt
The kit includes a bracket that installs using this factory fastener on the shock tower. Simply remove the bolt
Then you can install the separator/bracket assembly, and bolt it back down.
Then you can install the separator/bracket assembly, and bolt it back down.
With the factory connectors installed in the braided hoses, you can plug them into the cam cover and intake manifold. Use an AN wrench to tighten the connections without marring the fittings.
With the factory connectors installed in the braided hoses, you can plug them into the cam cover and intake manifold. Use an AN wrench to tighten the connections without marring the fittings.
Here’s the finished installation. The Ultimate version of the Bob’s Auto Sports oil separator gives the modern Coyote a racy look, and it protects the engine intake system from oil contamination.
Here’s the finished installation. The Ultimate version of the Bob’s Auto Sports oil separator gives the modern Coyote a racy look, and it protects the engine intake system from oil contamination.
After installing the separator, you can reinstall the engine cover. As you can see Steven Pellini also applied hydrocarbon graphics to the inlet tube of his Airaid cold-air intake system.
After installing the separator, you can reinstall the engine cover. As you can see Steven Pellini also applied hydrocarbon graphics to the inlet tube of his Airaid cold-air intake system.
Naturally, Steven already had installed a separator on his car, so he removed it and reinstalled one for our camera. However, that gave us an opportunity to see how much the Bob’s unit collected. In about 1,000 miles it had already gathered about 5 milliliters of oil that would have otherwise entered the engine’s induction. This amount is pretty typical, according the Steven. “Absolutely, we might be a little more work to install, but the extra effort is worth knowing you are keeping more oil out of your engine,” he said. “Many of our customers have switched to our brand and they are shocked at the difference.”
Naturally, Steven already had installed a separator on his car, so he removed it and reinstalled one for our camera. However, that gave us an opportunity to see how much the Bob’s unit collected. In about 1,000 miles it had already gathered a significant amount oil that would have otherwise entered the engine’s induction. This amount is pretty typical, according the Steven. “Absolutely, we might be a little more work to install, but the extra effort is worth knowing you are keeping more oil out of your engine,” he said. “Many of our customers have switched to our brand and they are shocked at the difference.”

Hydrographics Gallery

Comments

comments

Leave a Comment