I forget where I read it but I read an article from a Ford engineer who said the oil vapors can affect octane ratings, so if you're running an aftermarket tune, you can experience pre-detonation or pinging. The catch can stops that from happening.

In my former Bullitt, I tried a number of aftermarket tunes from several different companies and could never get away from the pinging issue, but I never installed a catch can. In my former '14 GT, I had a catch can installed when I had my tunes installed and never had a pinging issue. I don't know if there was a correlation but the proof was in the pudding for me.
Lee

 

not sure which bullitt you had, but the 2001 era 2v model, had no knock sensors and therefore the pcm didnt know if detonation was happening. the 14 you have has a knock sensor, and as soon as it detects detonation (it can detect it before you can hear it in most cases) it pulls a timing slightly to stop it. its not really proof to compare a car that has knock retard ability, to one that didnt, when only the knock sensor equipped car has the catch can. also, the amount of oil vapor that has to be present to make any effective constant change to octane would have to be massive, if anybody has that much vapor, they are having an issue with ring sealing. if roush says they havnt seen a need for it, then there isnt a need for it.

 

Do the 08 Bullitts have teh knock sensors?

 

Yeah, I guess those Ford engineers have no idea what they're talking about.

I'm not sure. The Bullitt had a unique computer that adjusted power levels dependent on octane levels. I was told that was one of the reasons I had issues getting a proper tune. Who knows the real reason.

 

the 2008 bullitt does have knock sensors

 

Kyle you should go into politics with that answer!

Well of course it's not mandatory, or it would be included with the Roushcharger kits. My question was whether the 5.OL Coyote engine actually has a problem of getting oil/oil mist back into the intake "with or without" a Roush Supercharger! Why do I ask? Because so many things sold today have "no real value" to the person who is scared into buying them. Being a returning Roush Customer having bought more than one Roushcharger, I was wondering if the Roush/Ford engineers or techs have opinions/facts on whether these oil separators are really an actual value since Ford doesn't to bother to put them on 5.0L engines in the Mustang GT? Some people think they are important & others have installed them & never seen any oil caught in the system. Can you get any information from Roush/Ford that really relates to the question? All I can get is theories based on no 1st hand evidence from Mustang enthusiasts.... & they don't agree!

 

im 100% certain that if this was an issue causing failures, or damage, that roush would include them as to prevent having to spend money warranty repairing customer cars.

 

The vapors will accumulate over time, my UPR can prevents these gases from "getting" to the passenger side intake "pvc" side.

 

I empty my passenger side air / oil separator when the oil gets to a certain point.
Will I have a motor failure if I didn't have the it, maybe not.
Will my intercooler have less oil film in it, yes !
Roush & jwog666 don't have to agree if it's needed or not, I see some value in having it.
.

 

not arguing anybodies opinion of value......however worrying about engine failures caused by normal pcv vapor isnt supported by any actual failures, so no need to worry, buy it, or dont buy it, but either way dont worry about it.