Catch Can Works
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 1,009
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From: slower lower DE
Catch Can Works
Put a catch can (CCA version) on at about 6K miles, now have about 26K. Hadn't drained it before since I didn't think I would be passing that much oil. Not S/C'd or turbo'd and don't race. Anyway, had to remove it to replace the evap emissions purge valve solendoid so I thought I would drain it. I was surprised at what came out. about 6 oz of oil.
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Team Owner
Joined: Sep 2000
Posts: 25,015
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From: Far NW 'burbs of Chicago
St. Jude Donor '13
Six oz of oil in 20k miles equals about one quart per 100,000 miles. That does not seem like a lot to me, our 2001 burned (no leaks, it all went through the engine) a qt every 3k-4k miles and was still doing fine when traded at 66k miles.
Sr.Random input generator
Joined: Jan 2008
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From: Sammamish, WA
Still, I installed one to my car as well since it is very easy, but I don't think it's that important, either.
Drifting
Joined: Feb 2010
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But I can guarantee in your situation, that you had suffered varnish built up in intake manifold, carbon/varnish in back of valves/valve stems, combustion chambers and piston tops with your 66k miles trade in!
Take an engine or two apart, then you can speak with authority pal!
Team Owner
Joined: Sep 2000
Posts: 25,015
Likes: 2,709
From: Far NW 'burbs of Chicago
St. Jude Donor '13
Unless motor is disassembled and verified, can't make assumption that motor still doing fine without proactive action taken! Performance deterioration is gradual, can't be felt unless you are extremely sensitive and cumulative built up will surly affect performance with high mileage!
But I can guarantee in your situation, that you had suffered varnish built up in intake manifold, carbon/varnish in back of valves/valve stems, combustion chambers and piston tops with your 66k miles trade in!
Take an engine or two apart, then you can speak with authority pal!
But I can guarantee in your situation, that you had suffered varnish built up in intake manifold, carbon/varnish in back of valves/valve stems, combustion chambers and piston tops with your 66k miles trade in!
Take an engine or two apart, then you can speak with authority pal!
My point was that reducing oil "burn" by 1 qt/100,000 miles is not likely to make a lot of difference.
Drifting
Joined: Feb 2010
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So far, the C5's I'm familiar with that are burning oil (mostly 2001's with the "improved" rings) are still doing well at over 100k miles. But I agree, that burning oil inside the engine is never a good thing.
My point was that reducing oil "burn" by 1 qt/100,000 miles is not likely to make a lot of difference.
My point was that reducing oil "burn" by 1 qt/100,000 miles is not likely to make a lot of difference.
To each his own Jim, I am only expressing my opinion, its all good!
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Intermediate
Joined: Jun 2008
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From: West Suburban Chicago IL
To me the issue is not having to add oil or burning a quart in 100K miles.
The issue is the reduced octane of fuel that results from the oil mixing with fuel at high throttle openings. Also, I have observed puddles of oil in the low spots of the ports in LS intake manifolds. Those puddles change the port shape, and presumably the air flow thru the ports.
Both of the above will affect performance.
The issue is the reduced octane of fuel that results from the oil mixing with fuel at high throttle openings. Also, I have observed puddles of oil in the low spots of the ports in LS intake manifolds. Those puddles change the port shape, and presumably the air flow thru the ports.
Both of the above will affect performance.
Team Owner
Joined: Sep 2000
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From: Far NW 'burbs of Chicago
St. Jude Donor '13
Drifting
Joined: Feb 2010
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Melting Slicks
Joined: Dec 2006
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Just emptied the catch can on the '12 dry-sump GS after a trip to Colorado (around 1,300 miles), and it had about 2 ounces. Not a whole lot, but still a crapload of oil otherwise going thru the intake. Not an 'enjoyable' mod, like window tint or aluminum pedals, but glad I did it. Hope GM fixes that crappy PCV valve on the C7 once and for all 
.
.
Drifting
Joined: Feb 2006
Posts: 1,339
Likes: 1
From: Lake Delton (WI Dells) WI
I put one of those glass fuel filters inline of the return hose in order to monitor the effectiveness of the catch can. I used to have the can mounted to the passenger side head. Now it's mounted on the front main support behind the bumper and has mainly copper tubing for an inlet hose. In my experience, what made a big difference for me is moving the can away from the source of heat and adding a copper intake line. These two things drastically helped in cooling the vapor allowing the oil to fall out of suspension more effectively. Before doing these two things I was seeing residual oil in the monitoring filter that was getting through the catch can. I am now seeing nothing in the monitoring filter.
Drifting
Joined: Feb 2010
Posts: 1,527
Likes: 34
I put one of those glass fuel filters inline of the return hose in order to monitor the effectiveness of the catch can. I used to have the can mounted to the passenger side head. Now it's mounted on the front main support behind the bumper and has mainly copper tubing for an inlet hose. In my experience, what made a big difference for me is moving the can away from the source of heat and adding a copper intake line. These two things drastically helped in cooling the vapor allowing the oil to fall out of suspension more effectively. Before doing these two things I was seeing residual oil in the monitoring filter that was getting through the catch can. I am now seeing nothing in the monitoring filter.
I don't know about your car, but on mine unlike the Z with its bumper air vent, temperature seems to feel the same as the side frame rail, fact is, metal do conduct heat, appears it averaged out in an confined area.
It would be interesting to used a non contact temperature gauge to take some readings!
Melting Slicks
Joined: Dec 2006
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Of course it does. Federal requirement (PCV= positive crankcase ventilation). It's not an electric valve, if that's what you meant. It's supposed to allow oil vapors only, but the crappy GM design obviously could be better. Baffles and steel wool is all that is needed, but how you build it makes a big difference.
Drifting
Joined: Feb 2006
Posts: 1,339
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From: Lake Delton (WI Dells) WI
Have you touch the front frame member behind the bumper where you'd mounted your catch can after a drive?
I don't know about your car, but on mine unlike the Z with its bumper air vent, temperature seems to feel the same as the side frame rail, fact is, metal do conduct heat, appears it averaged out in an confined area.
It would be interesting to used a non contact temperature gauge to take some readings!
I don't know about your car, but on mine unlike the Z with its bumper air vent, temperature seems to feel the same as the side frame rail, fact is, metal do conduct heat, appears it averaged out in an confined area.
It would be interesting to used a non contact temperature gauge to take some readings!
No, I have mainly just touched the can itself and that was cooler. I have my shroud cut for my Vararam, so it may be a bit different.
Drifting
Joined: Feb 2006
Posts: 1,339
Likes: 1
From: Lake Delton (WI Dells) WI
Of course it does. Federal requirement (PCV= positive crankcase ventilation). It's not an electric valve, if that's what you meant. It's supposed to allow oil vapors only, but the crappy GM design obviously could be better. Baffles and steel wool is all that is needed, but how you build it makes a big difference.
It has a PCV system, but not a valve. -THIS- is a typical PCV valve which is not present on the LS3. My LS1 has one.....don't know if the LS2 does or not.
Drifting
Joined: Feb 2010
Posts: 1,527
Likes: 34
Certainly getting air there helps! Glad that worked out for you!