MAPerformance Civic SI 1.5T PCV System & Catch Can Testing/Observations

[PowerPerLiter]

Just a curious question. What weight oil did you guys use for testing? Any theory as to how it could affect the factory crankcase evacuation strategy?

Sponsored

 

[MAPerformance]

Just a curious question. What weight oil did you guys use for testing? Any theory as to how it could affect the factory crankcase evacuation strategy?

stock weight

 

[feldsam]

Hello @PowerPerLiter, would you please post links to technical informations where I can learn more about intake reversion? Thank you!

They also programmed the cam phasing at light duty/ cruise to induce intake reversion. Which helps clean the intake valves by allowing fuel cleaners etc to reach the backside of the valves during very low pumping losses.

 

[Soulnchain]

So if I were to use a catch can and after say 6k miles find a few ml of fluid in it, what would that say? The baffles basically “condense” the oil vapors, but where does the liquid go after that?

 

[teders]

So if I were to use a catch can and after say 6k miles find a few ml of fluid in it, what would that say? The baffles basically “condense” the oil vapors, but where does the liquid go after that?

I think the only thing it would say is that the catch can is better at condensing the oil molecules out of the air, because it is cooler than the crank case.

 

[Soulnchain]

I think the only thing it would say is that the catch can is better at condensing the oil molecules out of the air, because it is cooler than the crank case.

so it’s doing what the engine baffles aren’t able to, making it a useful addition. Or am i missing something else?

 

[teders]

so it’s doing what the engine baffles aren’t able to, making it a useful addition. Or am i missing something else?

More like, the cooler air temperature of the catch can is performing the air/oil separation more efficiently, but that doesn't necessarily mean you still need it. The engine may be perfectly fine with the level of air-oil diffusion that is present without the catch can, the catch can just happens to be really good at it because it's a cooler environment.

It's like, the catch can is good at solving a problem that didn't exist In the first place.

 

[Soulnchain]

More like, the cooler air temperature of the catch can is performing the air/oil separation more efficiently, but that doesn't necessarily mean you still need it. The engine may be perfectly fine with the level of air-oil diffusion that is present without the catch can, the catch can just happens to be really good at it because it's a cooler environment.

It's like, the catch can is good at solving a problem that didn't exist In the first place.

I’m just wondering at what point the original baffles are too old/dirty to continue performing like they are supposed to considering there is no way to easily perform maintenance. Like an oil filter, sure filters good the firt couple thousand miles and you could probably never change it but at what point is it doing its job?

 

[teders]

I’m just wondering at what point the original baffles are too old/dirty to continue performing like they are supposed to considering there is no way to easily perform maintenance. Like an oil filter, sure filters good the firt couple thousand miles and you could probably never change it but at what point is it doing its job?

Yeah I mean eventually the engine will need cleaning. The way I see it though, there is a built in "filter", so adding a catch can is like installing a filter for your filter....is it really necessary?

 

[Soulnchain]

Yeah I mean eventually the engine will need cleaning. The way I see it though, there is a built in "filter", so adding a catch can is like installing a filter for your filter....is it really necessary?

Well, since one of the two filters you can actually clean in a matter of minutes, i guess yes. Ok, there is a bit of an initial expense but imo it might be worth it. Worst case scenario you just spent a fraction of the car’s value for peace of mind.

 

[teders]

Well, since one of the two filters you can actually clean in a matter of minutes, i guess yes. Ok, there is a bit of an initial expense but imo it might be worth it. Worst case scenario you just spent a fraction of the car’s value for peace of mind.

Perhaps, and when you put it as a cost comparison issue, it's a no brainer. However, I'm more of the opinion that 2016+ technology (L15b7) works fine on its own, without the need for 1990s technology (catch can).

 

[Soulnchain]

Perhaps, and when you put it as a cost comparison issue, it's a no brainer. However, I'm more of the opinion that 2016+ technology (L15b7) works fine on its own, without the need for 1990s technology (catch can).

I don’t know. I bought the can, installed it and removed it due to rattling noises. Fixed the issue a few months later and reinstalled it. Tested it for a few weeks (maybe 1k mi) and opened it up... well there was more fluid than i was hoping for. Which is why I don’t understand if it’s doing its job or my engines has more blow by than average. I just can’t see that stuff being caught by the honda baffles and just sitting there (were does it go from there?)

 

[teders]

I don’t know. I bought the can, installed it and removed it due to rattling noises. Fixed the issue a few months later and reinstalled it. Tested it for a few weeks (maybe 1k mi) and opened it up... well there was more fluid than i was hoping for. Which is why I don’t understand if it’s doing its job or my engines has more blow by than average. I just can’t see that stuff being caught by the honda baffles and just sitting there (were does it go from there?)

Well for one thing it doesn't condense out of the air as much, because on its own, it isn't passing through the cool environment that the catch can presents. So, it might just pass through the intake system without much "fall out" and then be ignited in the cylinder and out the exhaust.

 

[PowerPerLiter]

Hello @PowerPerLiter, would you please post links to technical informations where I can learn more about intake reversion? Thank you!

https://patents.google.com/patent/US7137377B2/en

In direct spark ignition engines, fuel is injected directly into each combustion chamber. Accordingly, less fuel may be inducted past the intake valves than in port injected engines. Inducting fuel past the valves cleans carbon deposits which may deposit on the valves due to positive crankcase ventilation (PCV) and/or exhaust gas recirculation (EGR). Thus, reducing the amount of fuel inducted past the valves can result in increased deposits.
One approach to clean such deposits, using conventional cam timing and a throttle is described in U.S. Pat. No. 6,178,944. This approach injected fuel during a valve overlap period when the engine is throttled to draw fuel back into the intake port.
However, the inventors herein have recognized a disadvantage with such an approach. For example, this approach requires throttling which can increase pumping losses and increase fuel consumption. The additional fuel injected during vavle overlap also may increase fuel consumption since an additional injection of fuel is used. Further, in some engines, throttled conditions may be performed for an insufficient amount of the available operating range so that the opportunity to perform valve cleaning may be limited.
At least some of the above disadvantages may be overcome by a method for a vehicle traveling on the road having an engine with adjustable valve operation, the method comprising: performing a valve cleaning operation for reducing deposits on a valve of the engine; and at least during said operation, adjusting valve timing of at least a valve of the engine and a fuel injection amount to increase an amount of fuel pushed back from a cylinder past the valve with deposits and then re-inducted through the valve with deposits.
In this way, valve cleaning can be performed without requiring throttling conditions (although cleaning may be performed during throttled conditions, if desired).
An advantage of the above aspect is that fuel injected during the valve adjustments can be used to clean carbon deposits accumulated on and around an intake valve.

 

[Syseen]

I'll start off with TLDR. So if someone's else has done this already my bad...

So I was going to look into the PCV system on my own 1.5 but literally that day the car got wrecked and the insurance company totalled it. So I did the rational thing and bought a 6mt sport hatchback

I needed a car, and I loved the EX after upgrading the suspension so I got another. but anyway I had also noticed before her death that my milage was down from mid 40mpg to low 30s and power was slightly down after 60k miles. Hence my suspicions about carbon on the valves. Alas I wasn't able to pull the head off and inspect the valves before the insurance company took it away.

Today however with the fat check from the insurance I was able to get all my slowly accumulated mods all at once. A new one of those mods is a mishimoto catch can. I pulled the pcv hose off and put the can In place. Now, granted my findings are faaaaaarrrrrrr from scientific but that old pcv hose is stanky.

It definitely smells oily and gassy. It didn't look wet inside,, and I dont know what is in the valve cover it could possibly be doing the same exact thing as a catch can, but now I have a brand new warranty so I'm not gonna fuck with that by pulling the cover and finding out. Instead I will check the can in a couple months and report back.

But based on how stinky the hose is *giggidy* and that there isn't anything between the manifold and valve cover I'm gonna reccomend a catch can.**

**(for now)

Sponsored