Is the Catch Can necessary
07-07-2014, 01:23 PM
#81
Pro
Talking about what other manufacturers do to keep oil out of the intake is completely relevant to this thread. God knows I don't want to turn this into yet another Porsche thread, which is why I mentioned three other manufacturers using air oil separators. There are more. Your opinion is yours, not necessarily mine. If your not interested in what other manufacturers are doing to address the problem, don't respond to those posts. I'd say it's more than a little amusing.
07-07-2014, 02:03 PM
#82
Racer
Thread Starter
Talking about what other manufacturers do to keep oil out of the intake is completely relevant to this thread. God knows I don't want to turn this into yet another Porsche thread, which is why I mentioned three other manufacturers using air oil separators. There are more. Your opinion is yours, not necessarily mine. If your not interested in what other manufacturers are doing to address the problem, don't respond to those posts. I'd say it's more than a little amusing.
07-07-2014, 02:30 PM
#83
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Talking about what other manufacturers do to keep oil out of the intake is completely relevant to this thread. God knows I don't want to turn this into yet another Porsche thread, which is why I mentioned three other manufacturers using air oil separators. There are more. Your opinion is yours, not necessarily mine. If your not interested in what other manufacturers are doing to address the problem, don't respond to those posts. I'd say it's more than a little amusing.
you are saying that since porsche uses Method S instead of Method P then it makes sense to supplement Method P with Addendum C, which is of course, preposterous.
especially when the porsche system is not used to "address the problem" of oily intake valves, because it doesn't work, obviously. the porsche system is there to perform the same function as the chevy pcv system, which also isn't 100% oil proof. so the porsche system is no more effective than the chevy system and therefore cannot possibly be contributory to the catch can discussion.
07-07-2014, 02:38 PM
#84
Race Director
It's been my feeling all along that if it was really necessary, with all the development and effort evident everywhere, it would be there from the factory. I am comfortable without a can.
07-07-2014, 03:27 PM
#85
Le Mans Master
07-07-2014, 08:24 PM
#86
Racer
Thread Starter
OP, Catch can or no catch can, I really don't care, but I don't want oil from the PVC entering the intake and coking my valves. If anyone has a better method I would sure like to know. This is not only a problem with GM, but every direct injection engine. If you think this condition doesn't exist you have the right to ignore it.
07-07-2014, 08:59 PM
#87
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OP, Catch can or no catch can, I really don't care, but I don't want oil from the PVC entering the intake and coking my valves. If anyone has a better method I would sure like to know. This is not only a problem with GM, but every direct injection engine. If you think this condition doesn't exist you have the right to ignore it.
07-07-2014, 10:08 PM
#88
Drifting
the condition exists and if I have said it once I've said it 4 times......the only way to keep the valves and intake clean is to remove the pcv system and vent to atmosphere through a filter which can cause condensation and poopy contamination in the crankcase or use a vacuum pump which will keep your crankcase squeaky clean and can give a 15-30 hp bump (no joke) except it costs way more and isn't available yet as a kit for the C7.
07-07-2014, 11:21 PM
#89
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Which as I’ve said a couple of times is illegal, because it makes your car pollute as much as about 50 properly controlled cars. We really are getting redundant here, but at least this time I won’t make the error of saying you are advocating that move. You are simply saying that it’s possible. Now you can call me a weenie again for saying that move would be irresponsible, all in good fun of course.
so the real end of the discussion answer is there is no way to prevent oil from entering the intake manifold from the pcv system unless you illegally modify the system. you can waste money on band aids but they will only fall off in the pool and gross everyone out.
07-07-2014, 11:59 PM
#90
Melting Slicks
OP, Catch can or no catch can, I really don't care, but I don't want oil from the PVC entering the intake and coking my valves. If anyone has a better method I would sure like to know. This is not only a problem with GM, but every direct injection engine. If you think this condition doesn't exist you have the right to ignore it.
...The 2015 Lamborghini Huracan uses direct injection plus port injection and an air oil separator..
..they say they are doing the duel injection for power and emissions but I wonder if will have the benefit of keeping the intake valves clean.http://r.search.yahoo.com/_ylt=A0SO8...zQyFyWe3EMPyA-
07-08-2014, 06:43 AM
#91
Race Director
Don't waste your time or money on a catch can. Gm engineers did an amazing job with the lt1 motor.
Jmo
Jmo
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07-08-2014, 07:47 AM
#92
Racer
Thread Starter
Your aware of the problem and I'll just bet you change your mind down the road. GM didn't invent the Direct injection theory they just ran with a great idea. That being said, I think they did a great job with this car. This is my 15th Corvette and it is the very best.
07-08-2014, 10:29 AM
#93
Racer
Thread Starter
The only complete cure is to install a vacuum pump and a catch can. That will completely eliminate any oil entering the manifold. Eventually this will be G M cure and have the excess oil drain back into the oil pan or dry sump system. If the catch can manufacturers are reading this they know I am absolutely correct, make it they will come.
07-08-2014, 11:31 AM
#94
Le Mans Master
Seems like an oil separator could be used to extract the oil, but instead of passing it thru the intake valve, why not inject it with the fuel, directly into the cylinder .. so you still combust the crankcase vapors, but don't pass the oil over the intake valve?
Just trying to think outside the box ..
Just trying to think outside the box ..
07-08-2014, 12:18 PM
#95
Racer
Thread Starter
Seems like an oil separator could be used to extract the oil, but instead of passing it thru the intake valve, why not inject it with the fuel, directly into the cylinder .. so you still combust the crankcase vapors, but don't pass the oil over the intake valve?
Just trying to think outside the box ..
Just trying to think outside the box ..
11-23-2014, 01:33 PM
#96
Safety Car
If you have a Z51 pull your air bridge and filter and see what is in there. You may be unpleasantly surprised. I had oil puddled in there at ~1500 miles with normal break in.
99% sure the sump tank is burping as that pcv hose is very oily.
We'll see what it looks like at the next oil change.
99% sure the sump tank is burping as that pcv hose is very oily.
We'll see what it looks like at the next oil change.
11-23-2014, 06:05 PM
#97
Team Owner
I'm thinking that if a catch can was really needed, an extra $100 cost of adding it while the engine was on the production line GM would've done it already. I'm not going to second guess the engine engineers at GM, I think they know what they're doing.
11-23-2014, 08:05 PM
#98
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Yup...installed one, then got about a tsp per 1000 miles, read the criswell article, took it off and sold it. I think gm is not stupid in this regard.
Last edited by Glen e; 01-29-2015 at 11:38 AM.
01-29-2015, 11:33 AM
#99
Melting Slicks
