spaceaholic

I have an A&A S/C going in the vehicle and have the LMR breather also being installed based on the expectation it is required to protect the engine from seal blow out and to inhibit oil injestion.

Subsequently was informed that LMR F/I Breather actually defeats/is ineffective for crank case ventilation because it " allows all the damaging combustion byproduct compounds to settle and accumulate in the engine oil greatly accelerating engine wear." The individual also indicated the LMR is simply a vented container that runs the clean and dirty sides together into and it only vents/relieves pressure and that the LMR ONLY relieves leaving all this damaging compounds in the crankcase to accumulate and cause accelerated wear and damage over time where

The LMR system apparently takes a line from the dry sump oil tank ( clean side,) the valley cover, (dirty side outlet where all crankcase vapors are removed from the engine), and the valve covers (that are part of the cleanside) all run together into one can ( and according to this individual they can/should NEVER be mixed).....a crankcase must have clean filtered air entering one side, and foul oil laden out the opposite and then LMR have vents on the can so not only are the clean and dirty mixed together, with only venting but none of the damaging compounds are ever removed...all are left in to mix with the oil. So according to this writer there is no real way to make the LMR work for anything but a containment vessel for a belt driven vacuum pump system.

The RX Monster system I was told has a different architecture which mitigates the above issues.


So who has the correct/most effective approach that protects the engine from damaging injestion, and is best for crank case venting of Forced Injection engines?


Really confused and want to do the right thing to preserve the longetivity of my engine while enjoying the benefits of F/I.

Scott

Unreal

RX is full of crap and I wouldn't run their stuff on my car. LMR is top notch. What you are saying is just the crap RX spews out to sell their cans.

If you want an RX monster setup, I fell for that and have one on my car. You can have it cheap so I can put something nice on. Been trying to get rid of it for awhile.

spaceaholic

Im interested in understanding the technical merits of their claim regarding either systems effectiveness...what is/isnt trueful about both systems respective design that makes one or the other ineffective (or less effective) then the other?

Late Model Racecraft

Scott, you can read a lot of information and speak to hundreds of different people about this matter. We have been building 1000+ HP Forced induction engines for over 15 years now and I would have to say our results speak for themselves. We would not install a product on our customer vehicles that we think would have any chance of having a negative effect. If you want to speak more directly about this matter or have further questions please feel free to call the shop and ask for Reid or myself.

You are going to love your new setup when it is completed. The C7s with the package you are installing drive amazing.


Steven Fereday

Higgs Boson

The LMR system works for a boosted application because the crankcase can become pressurized while in boost and performs the same task as the stock PCV system but in the opposite direction (direction is the wrong word, I should say opposite method - stock pulls, boost pushes).

The stock system actively sucks the gasses from the crankcase. LMR system on a naturally aspirated engine config is passive and not the best idea because it is not effective in removing any gasses. However, if the crankcase becomes pressurized then the LMR system can be passive and simply provide a way for the pressure to escape, which is its intention. The boost makes the LMR system active.

spaceaholic

Thanks for taking the time to reply Steve.....I would like to keep this on the public forum so all can benefit from this discussion. So with with respect to the LMR system and specifically as it is applied to direct impingement engines with forced induction ...how does it prevent fowling and what metrics do you have that demonstrate over time/miles that it is effective engine protection?

spaceaholic

So with a centri system (i.e. in my case A&A) on a daily driver, in which one lives mostly at 2000-2500 RPM's which is essentially operating the vehicle in an N/A mode because the blower doesnt really come into play above that threshold, I interpret your note to indicate the LMR really cant do its job. What do I do to protect the engine when the S/C is not engaged?

Higgs Boson

My post is meant to indicate the LMR system is the best option available for a boosted application.

You don't have to be in boost 100% of the time to get the benefit. You will see some boost every time you drive, even if it isn't wide open throttle full boost. A supercharger is always engaged; it runs off the engine serp belt. You will be fine.

Motohead279

I asked this question a few months ago on here and I never got a response. I do a lot of highway driving on my car because of where I live and am cruising between 1500 to 2000 RPMs most of the time. At that RPM range is there enough pressure to properly vent the gasses? Through discussions with a few people I was told a breather is a great idea on a track car, but not on a street car where you are normally driving under 2000 RPMs.

Higgs Boson

there isn't much pressure or gasses at 1500 rpms to vent. one good romp and it's clear. if you drive like a granny to the hair salon and never give it a little stick, why would you even spend money on a supercharger?

you don't have to worry about it. maybe on an Oldsmobile cutlass that never sees 4000 rpm in its whole life, but I would suppose that isn't the life of a supercharged corvette.......

Unreal

Most factory cars don't have active vent systems, and anything older does not yet they see tons of miles without issues. I guess if you plan to drive like a granny, never get your oil hot, and change it every 20k miles than this maybe a slight area of concern, but even then I doubt it. Any high HP car I know is running a system like the LMR system. Even my RX when it is on (when I'm not repairing it from breaking over and over) is setup to be vented and just catch any oil from the valley cover to intake.

Higgs Boson

every single car made since the 60s/70s has an active vent system called Positive Crankcase Ventilation.

Unreal

Yes, but not all are setup like RX claims it has to be done.

robertf97

I want the PCV but not so much that it puts oil in the intake. I think what ECS does on their set-up is the best compromise. They route the PCV hoses to the air filter box upstream of the air filter so it is going to get some vacuum occasionally, yet any oil has to make it through the filter before it can get in the engine. If I ever do see any oil in the filter/box I have a $17 ebay catch can that I can add in line. I also remove the ***** in my PCV check valves.

breecher_7

Truth..

The RX Monster Can setup appears to work just fine under boost, it does a good job of collecting oil.. But during normal driving or hard engine braking it doesnt seem to do very well. All my experience with it would be on the Gen III and IV engines but i would imagine the gen V would be the same. Even with this system in place and hooked up as directed it still never keeps oil out of the intake manifold. Whatever media or lack of media they put in those cans does not work and does not keep the oil in the can, period. It gets sucked right back into the intake and makes a mess. We just had to pull a head on a buddy of mines car last week because it was leaking coolant. Sure enough the intake was full of oil and there was buildup around the intake valve.

I have yet to see one of these "catch can" setups that actually work... Pretty sure we are going back to a regular breather can only setup. I would rather see some smoke and smell the crap than have oil in the intake manifold.

RpeterK

The only way to guarantee not getting oil in the intake is to eliminate the path. Oil is a bad thing on earlier cars and has only been made worse with direct injection cars. Doesnt matter what maker as they are all having issues of sorts and if you do some catch can research you'll find Bmw and just about any brand with ingestion issues. Big problem on direct injection engines is there is no longer fuel sprayed onto the valve stem/head area to help provide a washing effect so this tends to make for a build up over time. There have been some pics posted here of early coating happening.

spaceaholic

Here's what I received from the RX rep:

Quote:

The LMR system works for a boosted application because the crankcase can become pressurized while in boost and performs the same task as the stock PCV system but in the opposite direction (direction is the wrong word, I should say opposite method - stock pulls, boost pushes).

This allows most of the damaging compounds to stay in, and accumulate in the crankcase. What God Particle is describing cannot evacuate. Think of this as a room. This room has a pipe in the middle constantly spewing smoke into it. Open one window, and some smoke is pushed out from the pressure of the smoke entering, but most remains in the room.. Same with a system that only vents. You never want pressure in a crankcase. Now open a window on the opposite end of the room with a fan drawing the smoke out, and the frsh air entering the opposite end flushes and replaces what the fan is evacuating. That simple. There is not a single professional drag racer or road racer that would ever run a vented only system.

The stock system actively sucks the gasses from the crankcase. LMR system on a naturally aspirated engine config is passive and not the best idea because it is not effective in removing any gasses. However, if the crankcase becomes pressurized then the LMR system can be passive and simply provide a way for the pressure to escape, which is its intention. The boost makes the LMR system active.

Watch this video to understand that an engine needs the damaging combustion byproducts evacuated at all times at a steady and constant rate. Allowing these to accumulate until pressure builds and pushes a small amount out a vent is the absolute least effective way to evacuate. A belt driven vacuum pump is the best, most effective but they wont live long on the street:

https://www.youtube.com/watch?v=EPIfI9aZHt4 You MUST have filtered fresh air entering one part of the crankcase making up for and flushing the damaging byproducts out the other side of the crankcase. The RX systems all have AN fittings now (no plastic valves to break) and high quality inline checkvalves.




Now there is no question LMR makes some of the best high HP builds out there, and the quality of work is top notch, but the lack of understanding proper crankcase evacuation is widespread. One only has to do oil analysis a few thousand miles with a vented PCV system deleted engine to see how severe the accumulation of these damaging compounds i. No politics or arguing....factual data.

You MUST evacuate (not just vent pressure) and pull vacuum at all times possible, and have a filtered fresh air supply (clean) to make up for, and flush the damaging compounds out as soon as they enter. The damage is gradual over time, but is real...and a simple oil analysis will show this. Why gamble on something so straight forward? The Elite Engineering E2 system also provides proper evacuation, but they are the only 2 on the market currently.

Here is a picture showing the rocker arms beginning to corrode from using a "pressure vent" only system:


This is only 6 months running a vented system. I urge anyone that has had a vented system on to simply pull a valve cover and look underneath at the rust starting and the water and condensation present.......it is impossible for a vented system to do more than push out a small amount of these contaminats:

Water
Unburnt fuel
Sulfuric acid
abrasive soot and carbon particles
etc.

All engines in order to live a long life must have evacuations, and relieving pressure is NOT evacuation. With affordable systems available that do all thats needed, why run the risk? And again, anyone can do an oil analysis and see this first hand and they dont have to blindly follow anyone's claims.

Higgs Boson

Sounds like he has a sales pitch ready to go. You think if anyone else emails him he will have a differently worded reply that outlines the same theory or he will just copy/paste?

Pretty simple to see that the outside of that engine is also rusted, the headers, the heads where the valve cover seals, etc. Nice "close up" that takes everything out of context.

Should I post pictures of engines that used passive systems (on non boosted motors no less) for 20 or 30 years with no rust?

Either way, as I have said before, it is better to have an active system if you are NA. For FI I would go with something like the LMR.

If you go with an active system because you are NA, on the LT motor, I would use the stock system and not waste your money. The stock PCV system on the wet sump engine is very good, I have not had a single drop make it into the intake manifold or tube/TB.

On older LSx motors, the stock system sucks (more than it should) but still it is debatable if one should install a catch can. You have to look at the end result. Does the can "catch" oil (mist)? Yes. Does it prevent it from getting into the intake? NO. So then why even go there? Do it right the first time, eliminate the stock system completely or just leave it stock and clean your top end regularly.

RpeterK

One other key issue Rx brought up is a vacuum pump.
The whole purpose of it is to create a vacuum in the crankcase and it doesnt use any fresh air in. So the only thing it pumps is blowby.

robertf97

I don't understand why they want fresh air coming in. Air has oxygen and moisture in it that can oxidize or corrode when the car is turned off. I'd rather have just a little vacuum.