So...you don't feel a Catch Can is necessary in a Wet Sump car?!? Check this out
07-23-2015, 01:32 PM
#121
All DI engines have this issue and yes, as the deposits form, several things occur.
1. excessive premature wear of the valve guides (haven't had to deal with this since the 60's/70's)
2. A/F mixture in each cylinder becomes unequal as the amount of air entering is obstructed yet the DI injectors will still deliver the same amount of fuel to each based on the upstream O2's, MAF, MAP, etc. so unequal power contribution from each. As the deposits do not form equally. The valves b\nearest the oil ingress will have more severe build-up than the furthest ones in general.
3. At idle and during the transition from idle hesitation/stumble and misfires will become more common at low rpms vs higher as the disruption of the air entering each cylinder has more of a negative effect when the flow and velocity is low VS higher RPM's when the flow can overcome the disruption. As build up increases it will effect all operating levels.
4. If/when the deposits build to a certain point large chunks can and do break off and can/do get stuck between the valve and seat causing lost compression and if open far enough a bent valve from PTV contact.
5. As the deposits shed smaller particles they can/do get forced between the piston and cylinder wall causing scouring.
Anyone doubting the severity and how quickly these deposits build, just ask a tuner shop that has removed the intake manifold what they see (if they actually look into the intake ports at the intake valves).
Every time I do a Google search on "intake valve deposits with direct injection" or similar more examples pop up in the images including more articles and papers from the industry, but only the "PR Talking heads" from any of the auto makers, and they all deny they have an issue with this, yet every tech that tears DI engines down can attest to what they see.
https://www.google.com/search?q=inta...ih=775:cheers:
1. excessive premature wear of the valve guides (haven't had to deal with this since the 60's/70's)
2. A/F mixture in each cylinder becomes unequal as the amount of air entering is obstructed yet the DI injectors will still deliver the same amount of fuel to each based on the upstream O2's, MAF, MAP, etc. so unequal power contribution from each. As the deposits do not form equally. The valves b\nearest the oil ingress will have more severe build-up than the furthest ones in general.
3. At idle and during the transition from idle hesitation/stumble and misfires will become more common at low rpms vs higher as the disruption of the air entering each cylinder has more of a negative effect when the flow and velocity is low VS higher RPM's when the flow can overcome the disruption. As build up increases it will effect all operating levels.
4. If/when the deposits build to a certain point large chunks can and do break off and can/do get stuck between the valve and seat causing lost compression and if open far enough a bent valve from PTV contact.
5. As the deposits shed smaller particles they can/do get forced between the piston and cylinder wall causing scouring.
Anyone doubting the severity and how quickly these deposits build, just ask a tuner shop that has removed the intake manifold what they see (if they actually look into the intake ports at the intake valves).
Every time I do a Google search on "intake valve deposits with direct injection" or similar more examples pop up in the images including more articles and papers from the industry, but only the "PR Talking heads" from any of the auto makers, and they all deny they have an issue with this, yet every tech that tears DI engines down can attest to what they see.
https://www.google.com/search?q=inta...ih=775:cheers:
Heres the way i viewed this "problem". I always thought that maybe at 40k-60k miles you would see decent build up. maybe be down on power by like 8HP. then around 80k-100k miles you should get a cleaning done. As i would think ANY engine DI or not is not running at 100% like it once did. Its normal for any engine to lose efficiency. i mean our cars have a 100k mile warranty. at 80k miles people are going to be bitching about there power loss
The guy in the video made it seem like by 20k miles you are down 10HP and it will only get worse. by 100k miles you would be down like 40-50HP. Which i do not believe because GM wont sell a product that would be THAT bad.
Last edited by MikeLsx; 07-23-2015 at 01:34 PM.
07-23-2015, 01:36 PM
#122
Melting Slicks
find it so hard to believe GM would put a car on the road that in a matter of year of driving you are already losing power. I believe this is a real problem, but after one year?[/QUOTE]
Hmm ... have you seen GMs track record? A catch can is a real good "preventive" maintenance.
Not all catch cans are made the same. Just like not all tires for Corvettes are made the same, some do well in wet conditions, some do well dry conditions, some don't do well at all in any condition because they're just cheap rubber tires.
Hmm ... have you seen GMs track record? A catch can is a real good "preventive" maintenance.
Not all catch cans are made the same. Just like not all tires for Corvettes are made the same, some do well in wet conditions, some do well dry conditions, some don't do well at all in any condition because they're just cheap rubber tires.
07-23-2015, 01:38 PM
#123
Melting Slicks
Not sure you need one for a Z06. My Z has about 5k miles on it and I check the oil regularly and the stick still marks in the exact same place since I brought it home so I have not lost any. I filled it to the same mark on my 500 mile change and have no issues/need for a catch can.
In all my years of owning several LS based vehicles, I have never seen GM be consistent in their builds of the LS motor. Some dyno more, some dyno less. I've seen it first hand on the dyno.
07-23-2015, 02:02 PM
#124
Melting Slicks
Anyone doubting the severity of how quickly it builds, and just how severe it is as far as effecting the flow (remember these valves and ports were designed for utmost efficiency, and ANY disruption to how they flow is a negative. Click on this link anyone that is not aware just how severe of an issue this is affecting every auto maker in the world currently:
https://www.google.com/search?q=inta...ih=775:cheers:
https://www.google.com/search?q=inta...ih=775:cheers:
07-23-2015, 10:27 PM
#125
I'm Batman..
Pro Mechanic
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Member Since: Apr 2014
Location: Lehigh Acres FL
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Anyone doubting the severity of how quickly it builds, and just how severe it is as far as effecting the flow (remember these valves and ports were designed for utmost efficiency, and ANY disruption to how they flow is a negative. Click on this link anyone that is not aware just how severe of an issue this is affecting every auto maker in the world currently:
https://www.google.com/search?q=inta...ih=775:cheers:
https://www.google.com/search?q=inta...ih=775:cheers:
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WarBaby (10-23-2015)
07-24-2015, 11:17 AM
#126
Safety Car
Not sure you need one for a Z06. My Z has about 5k miles on it and I check the oil regularly and the stick still marks in the exact same place since I brought it home so I have not lost any. I filled it to the same mark on my 500 mile change and have no issues/need for a catch can.
There's a thread on the other C7 forum that goes into great detail.
07-24-2015, 11:34 AM
#128
Melting Slicks
07-24-2015, 11:45 AM
#129
Burning Brakes
I have a system on my car now by UPR. Great setup, I was also trying the LMR one as I was looking to make some changes to their setup. I have been dealing with catch cans for years, with my DI Camaro first. There are only a handful of systems I would use on my cars...
07-24-2015, 01:33 PM
#130
Melting Slicks
Already back together... Don't believe me.... I have a system on my car now by UPR. Great setup, I was also trying the LMR one as I was looking to make some changes to their setup. I have been dealing with catch cans for years, with my DI Camaro first. There are only a handful of systems I would use on my cars...
I have a system on my car now by UPR. Great setup, I was also trying the LMR one as I was looking to make some changes to their setup. I have been dealing with catch cans for years, with my DI Camaro first. There are only a handful of systems I would use on my cars...There was a guy early on with the C7's with a yellow one he tore down at a few thousand miles here that posted good pics. That was at the beginning of people doing so. I will try and find his thread. I think he was doing heads/cam at tear down.
08-02-2015, 09:54 PM
#133
Drifting
Has anyone had any experience with catch cans and CA smog checks? There is a poster on another forum indicating the catch can will cause your car to fail CA smog check and will also void your warranty. I find both claims difficult to believe but wondering if anyone has info?
08-03-2015, 12:14 AM
#134
Drifting
3M makes a cleaning kit for injection systems that includes a can of spray that you spray directly into your intake manifold/TB ( you must remove your CAI pipe). BG also has products that can clean the intake valves on DI engines. If you go to their website, it shows how much carbon build-up can occur in 30K. And... if your engine is breathing lots of oil due to over filling or overflow, it will occur much more quickly.
08-03-2015, 08:02 AM
#135
3M makes a cleaning kit for injection systems that includes a can of spray that you spray directly into your intake manifold/TB ( you must remove your CAI pipe). BG also has products that can clean the intake valves on DI engines. If you go to their website, it shows how much carbon build-up can occur in 30K. And... if your engine is breathing lots of oil due to over filling or overflow, it will occur much more quickly.
08-04-2015, 12:26 AM
#136
Drifting
I changed out my intake manifold for a ported one in about 1/2 hr. So... one can quickly pull your intake manifold and look straight in to see the carbon buildup. Worst case scenario would be to have a dealer clean them with ground walnut shells to blast away the carbon deposits. The carbon and walnut abrasive then just burns up harmlessly when you start it back up.
08-04-2015, 09:09 AM
#137
Burning Brakes
I changed out my intake manifold for a ported one in about 1/2 hr. So... one can quickly pull your intake manifold and look straight in to see the carbon buildup. Worst case scenario would be to have a dealer clean them with ground walnut shells to blast away the carbon deposits. The carbon and walnut abrasive then just burns up harmlessly when you start it back up.
08-04-2015, 09:11 AM
#138
For me i just dont wanna mess around with the oil/carbon system in the car. for two reasons, one is i will probably install a can wrong. two is that i would rather do the cleaning as i like the idea more. its more simple for me to do. open the intake, spray and pray.
Last edited by MikeLsx; 08-04-2015 at 09:15 AM.
08-04-2015, 12:27 PM
#139
Safety Car
Gm has a upper engine cleaner I read about it at the corvette knowledge center I traced the part number and found it in quart and spray cans.
I plan on taking mine apart about 20K to see what is happening if it needs cleaning manually I will clean it then use this stuff.
I plan on taking mine apart about 20K to see what is happening if it needs cleaning manually I will clean it then use this stuff.
Last edited by bob guzzy; 08-04-2015 at 12:30 PM.
08-04-2015, 01:12 PM
#140
Drifting
Member Since: Feb 2015
Location: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
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After reading seemingly miles of interesting information here (THANKS) I have made the decision to install a catch can on my Z06 with now 4k miles.
The reasoning for those to hammer me on is..... I DO NOT want any loss of power of the next 10 years. I do not want to walnut blast my heads in 30k miles and then again at 60k. Once at maybe 80k is ok. I DO NOT want to run a cleaner through the engine then create multiple other issues with carbon etc. everywhere. The catch can while fairly inexpensive seems to be a 90% fix to the problem. About every HP engine building I know uses them on NON DI engines what's that say!
To save me from going back does anyone know of the companies that make "good" catch cans for the LT4 that they can list here?
The reasoning for those to hammer me on is..... I DO NOT want any loss of power of the next 10 years. I do not want to walnut blast my heads in 30k miles and then again at 60k. Once at maybe 80k is ok. I DO NOT want to run a cleaner through the engine then create multiple other issues with carbon etc. everywhere. The catch can while fairly inexpensive seems to be a 90% fix to the problem. About every HP engine building I know uses them on NON DI engines what's that say!
To save me from going back does anyone know of the companies that make "good" catch cans for the LT4 that they can list here?
