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Discussion Starter · #1 ·
Have a 2022 jailbreak on order. I read that they are port injection motors so I figured a catch can may not be needed as compared to the direct injection motors. I have one on my Tahoe because of this.

Are you guys still running catch cans on these cars anyway? If so what brand?
 

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21 Challenger Redeye, 21 Trackhawk
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Yes I still run a catch can on the Trackhawk and Redeye, currently building one for the Rubicon 4XE.
I use UPR.
Pic is what came out of the Trackhawk catch can at 4000 miles.
Hand Drinkware Stemware Barware Fluid

Liquid Drinkware Rusty nail Ingredient Fluid
 

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Discussion Starter · #3 ·
Nice. I’ll probably run one then. I was also wondering if boost screws these things up as well.
 

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Discussion Starter · #6 ·
I haven't put one on any of the Hemi cars I've ever owned. I figured if it was detrimental the factory would have added it. But, could it be detrimental?
I think they are a must for any direct injection motor. The carbon buildup is horrendous because the fuel can't wash the deposits away. I'm 50/50 on a port injection motor if they need it because the injectors just wash all that crap into the cylinders to burn.

I think the factory doesn't add them because it's another maintenance item and most people won't be remembering to empty these things every 3-4k miles.
 

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+1 for the UPR. Mine was nearly filled up completely at my last oil change--it's definitely doing its job.
 

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2020 Challenger Hellraisin Scat Pack.
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+1 for the UPR. Mine was nearly filled up completely at my last oil change--it's definitely doing its job.
For real confirmation check the intake walls for any presence of oil making it past the catch can.
 

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I think they are a must for any direct injection motor. The carbon buildup is horrendous because the fuel can't wash the deposits away. I'm 50/50 on a port injection motor if they need it because the injectors just wash all that crap into the cylinders to burn.

I think the factory doesn't add them because it's another maintenance item and most people won't be remembering to empty these things every 3-4k miles.
There is some back flow of combustion gases in a DFI engine. This is done on purpose. If one uses a gasoline with a good detergent -- one is Chevron with Techron -- this back wash will remove (or keep) deposits from forming on the back of the intake valves.
 

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2020 Challenger Hellraisin Scat Pack.
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Every drop in the can is a drop that would have gone through without it. I don't know if its filter is 100% effective, but it's definitely better than not having one at all.
Those couple of ounces of oil in the catch can are of no real consequence. It ia actually fortunate the catch can doesn't catch more oil. It would fill up and the risk is high a slug of that oil could get sucked out of the can and hydraulic lock the engine.

Also, every gallon of gasoline contains nearly an ounce of oil.
 

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2022 Jailbreak
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No engine ever failed due to deposits on the intake runners. Most gunk on a valve is a result of unburned fuel, not oil in the PCV system (assuming engine is operating normally and isn't burning oil like the case with a bad piston o-ring). I won't make this post too long, I'll just end it by saying the real reason for needing a catch can on the GT500 and our cars is that during WOT, the crankcase pressure gets high enough to push some small amount of oil into the intake through the dirty side of the PCV system. Oil has a 0 octane rating and if enough is ingested, it can result in momentary reduction of power as the octane rating of the fuel in the cylinder combustion chamber is reduced. A catch can prevents this from occurring.

I don't believe the snake oil that says a catch can prevents engine or valve failure. I use it so that the engine does what it is supposed to do when I need it most.
 

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Discussion Starter · #14 · (Edited)
I've seen some seriously gunked up valves on Direct Injection engines such as used in the GM trucks. The oil is just put back into the intake and gets all over the valves. The fuel in a direct injection motor is shot into the cylinder, not on top of the valves. So there is nothing to clean the valves off. Nothing cleans off that crap better than a shit load of fuel squirting the valves clean.

I just found this with a quick search from Valvoline:

I run a can in my Tahoe, but I do not run one in my LS2 GTO which is port injection. Just wanted to see the concensus here about running one on a red eye.

Someone brought up a good point about warranty, would this be an issue? That alone may make me bag the can on this car.
 

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No engine ever failed due to deposits on the intake runners. Most gunk on a valve is a result of unburned fuel, not oil in the PCV system (assuming engine is operating normally and isn't burning oil like the case with a bad piston o-ring). I won't make this post too long, I'll just end it by saying the real reason for needing a catch can on the GT500 and our cars is that during WOT, the crankcase pressure gets high enough to push some small amount of oil into the intake through the dirty side of the PCV system. Oil has a 0 octane rating and if enough is ingested, it can result in momentary reduction of power as the octane rating of the fuel in the cylinder combustion chamber is reduced. A catch can prevents this from occurring.

I don't believe the snake oil that says a catch can prevents engine or valve failure. I use it so that the engine does what it is supposed to do when I need it most.
Timing retard is normal under hard acceleration and has nothing to do with oil vapor from the crankcase. Timing retards upon hard acceleration not due to oil in the fuel but because the engine controller riches up the mixture to one more conducive to power generation and this results in the need for less timing advance.

Have to question if there's enough oil to affect timing and if any reduction in timing is from this oil.

The fuel is rated at 91 octane even with a bit of oil the refinery adds for corrosion protection. A tiny bit more oil is not going to affect the octane rating to any noticeable degree. The amount of oil in a pic someone posted didn't call happen at once, but over a good number of miles and time.

I believe the actual effect on engine timing due to excessive amount of oil vapor passing through the crankcase ventilation system is more imagined than real.
 

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I did a test on my purple Hellcat where I emptied the can and then went out and did 2-3 quarter mile WOT pulls on a back road. It put about a half ounce of oil in the catch can.
 

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Oil has the effect of lowering the octane of your fuel, you absolutely need to keep it out of the combustion process.

My 2016 HC had a terrible PCV system, lots of oil pullover, a catch can is a must on these engines.
 
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Timing retard is normal under hard acceleration and has nothing to do with oil vapor from the crankcase. Timing retards upon hard acceleration not due to oil in the fuel but because the engine controller riches up the mixture to one more conducive to power generation and this results in the need for less timing advance.

Have to question if there's enough oil to affect timing and if any reduction in timing is from this oil.

The fuel is rated at 91 octane even with a bit of oil the refinery adds for corrosion protection. A tiny bit more oil is not going to affect the octane rating to any noticeable degree. The amount of oil in a pic someone posted didn't call happen at once, but over a good number of miles and time.

I believe the actual effect on engine timing due to excessive amount of oil vapor passing through the crankcase ventilation system is more imagined than real.
Your understanding of combustion is flawed. Unless you've been fortunate enough to work on a fully instrumented dyno at an OEM I wouldn't make that statement.
 

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2019 Challenger Hellcat Widebody (destroyer grey)
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No engine ever failed due to deposits on the intake runners. Most gunk on a valve is a result of unburned fuel, not oil in the PCV system (assuming engine is operating normally and isn't burning oil like the case with a bad piston o-ring). I won't make this post too long, I'll just end it by saying the real reason for needing a catch can on the GT500 and our cars is that during WOT, the crankcase pressure gets high enough to push some small amount of oil into the intake through the dirty side of the PCV system. Oil has a 0 octane rating and if enough is ingested, it can result in momentary reduction of power as the octane rating of the fuel in the cylinder combustion chamber is reduced. A catch can prevents this from occurring.

I don't believe the snake oil that says a catch can prevents engine or valve failure. I use it so that the engine does what it is supposed to do when I need it most.
This is what I was about to say. It's more for stopping the addition of oil vapors from getting into the combustion, that could lead to lowering octane rating of the fuel and causing detonation that would pull timing.
 
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