Notices
C8 General Discussion The place to discuss the next generation of Corvette.
Sponsored by:
Sponsored by:

C8 Catch Can Controversy

Thread Tools
 
Search this Thread
 
Old 07-12-2022, 04:44 PM
  #1  
trynt
Racer
Thread Starter
 
trynt's Avatar
 
Member Since: Mar 2010
Location: Minnesota
Posts: 421
Received 50 Likes on 33 Posts

Default C8 Catch Can Controversy

Last November, one of the first things I did after picking up my 2022 HTC was to install a UPR Products catch can. Very soon afterwards I read they weren't needed on a C8 and were a waste of money. Fast forward 6500 miles and you can see the amount of oil in the can. Admittedly not much. I would guess about one third of what was deposited in my C7 GS. Is it worth the money? I don't know. You be the judge.



The following users liked this post:
CorvetteBrent (07-15-2022)

Popular Reply

07-12-2022, 04:50 PM
TBD
Burning Brakes
 
TBD's Avatar
 
Member Since: Aug 2008
Posts: 1,094
Received 264 Likes on 113 Posts
Default

Engineers who designed the engine and GM that warranties the engine don’t think a catch can is needed.

The engineers know a whole lot more about engines than I do; GM sure doesn’t want to pay for warranty work.

I will trust their collective judgement.

Cheers!
Old 07-12-2022, 04:50 PM
  #2  
TBD
Burning Brakes
 
TBD's Avatar
 
Member Since: Aug 2008
Posts: 1,094
Received 264 Likes on 113 Posts

Default

Engineers who designed the engine and GM that warranties the engine don’t think a catch can is needed.

The engineers know a whole lot more about engines than I do; GM sure doesn’t want to pay for warranty work.

I will trust their collective judgement.

Cheers!
The following 11 users liked this post by TBD:
bkramme (07-15-2022), CorvetteMike2024 (07-12-2022), Floridasky (07-12-2022), Foosh (07-13-2022), hamta (07-12-2022), Jim-Layhee (07-14-2022), M2Pilot (07-12-2022), Rich Mickol (07-12-2022), tadda (07-12-2022), Z06Aggie (07-14-2022), Zormecteon (07-12-2022) and 6 others liked this post. (Show less...)
Old 07-12-2022, 05:00 PM
  #3  
Red C8 of Jax
Safety Car
 
Red C8 of Jax's Avatar
 
Member Since: Sep 2001
Location: Jacksonville FL
Posts: 4,280
Received 1,123 Likes on 758 Posts

Default

Again
The following 8 users liked this post by Red C8 of Jax:
BIG Dave (07-12-2022), Foosh (07-13-2022), hamta (07-12-2022), hawkgfr (07-13-2022), itsonlyairandfuel (07-13-2022), johnodrake (07-14-2022), Ranger5 (07-20-2022), Tim0shel (07-13-2022) and 3 others liked this post. (Show less...)
Old 07-12-2022, 05:06 PM
  #4  
Red Mist Rulz
Race Director
 
Red Mist Rulz's Avatar
 
Member Since: Sep 2016
Posts: 11,229
Received 8,606 Likes on 4,306 Posts
Default

Originally Posted by TBD
Engineers who designed the engine and GM that warranties the engine don’t think a catch can is needed.

The engineers know a whole lot more about engines than I do; GM sure doesn’t want to pay for warranty work.

I will trust their collective judgement.

Cheers!
GM only needs the engine to operate for 5 years. After that you're on your own. Any oil in the catch can didn't coat the MAF or the intake valves.
The following 7 users liked this post by Red Mist Rulz:
blkvett01 (07-13-2022), CorvetteBrent (07-15-2022), dohabandit (07-15-2022), Hillslam (07-12-2022), joliett (07-15-2022), Maxie2U (07-12-2022), MikeinAZ (07-14-2022) and 2 others liked this post. (Show less...)
Old 07-12-2022, 05:16 PM
  #5  
AzDave47
Race Director
Support Corvetteforum!
 
AzDave47's Avatar
 
Member Since: Feb 2011
Location: AZ
Posts: 13,276
Received 4,539 Likes on 2,614 Posts

Default

If you did road course events you would have 4oz.+ per day with the full throttle, compression braking, full throttle cycling. I would get that much (what your picture showed) in 2000-3000- miles of highway driving, but 4 oz. each track day in my LS7, stock or full HCI. Only in road course driving does any real amount of oil go thru the PCV system if the engine is working right.
The following users liked this post:
MikeinAZ (07-14-2022)
Old 07-12-2022, 05:23 PM
  #6  
Kracka
Le Mans Master
 
Kracka's Avatar
 
Member Since: Jan 2014
Location: Oak Point, TX
Posts: 9,684
Received 5,823 Likes on 2,961 Posts

Default

Originally Posted by DSOMrulz
GM only needs the engine to operate for 5 years. After that you're on your own. Any oil in the catch can didn't coat the MAF or the intake valves.
Blow-by oil, catch-can or not, will never coat the MAF due to the C8's plumbing. If you get a film of oil on your C8's MAF it is from an over-oiled aftermarket cotton gauze air filter.
The following users liked this post:
hamta (07-12-2022)
Old 07-12-2022, 05:23 PM
  #7  
BlindSpot
Le Mans Master
 
BlindSpot's Avatar
 
Member Since: May 2016
Location: LWR, FL
Posts: 5,132
Received 1,369 Likes on 908 Posts
Default

The big save a catch can does is the oil deposits that turn to carbon buildup on the intake valves. The factory engineering isn’t too concerned about this BC there are maintenance procedures to fix this, albeit incredibly expensive. Still the factory won’t be concerned

I would be on the fence installing one on an NA engine. Boosted is an entirely different situation. When I boosted my C6 it was foolish not to go with a catch can.
The following users liked this post:
CorvetteBrent (07-15-2022)
Old 07-12-2022, 05:25 PM
  #8  
rkrupka
Pro
 
rkrupka's Avatar
 
Member Since: Jan 2014
Posts: 584
Received 277 Likes on 175 Posts

Default

Do they add catch cans on the cars at the Ron Fellows school?
The following 2 users liked this post by rkrupka:
CorvetteBrent (07-15-2022), ednsd (07-13-2022)
Old 07-12-2022, 05:27 PM
  #9  
Shoal07
Burning Brakes

 
Shoal07's Avatar
 
Member Since: Apr 2022
Location: Northern VA
Posts: 782
Received 642 Likes on 309 Posts
2022 C8 of the Year Finalist - Unmodified
Default

The GM engineers answered this in an interview a while back. The way their dry sump system works that oil would have made it back into the sump not the cylinders.
The following 6 users liked this post by Shoal07:
Andybump (07-12-2022), bkramme (07-15-2022), Chemdawg99 (07-12-2022), hamta (07-13-2022), johnodrake (07-14-2022), Kevin A Jones (07-12-2022) and 1 others liked this post. (Show less...)
Old 07-12-2022, 05:40 PM
  #10  
vetteLT193
Melting Slicks
Support Corvetteforum!
 
vetteLT193's Avatar
 
Member Since: Jul 2002
Location: Tallahassee fl
Posts: 2,150
Received 526 Likes on 316 Posts

Default

It may not need one but it won't hurt. GM is a bean counting company which is why it isn't there factory just like a manual way to access the rear hatch
The following users liked this post:
Maxie2U (07-12-2022)
Old 07-12-2022, 06:53 PM
  #11  
Chemdawg99
Administrator

Support Corvetteforum!
 
Chemdawg99's Avatar
 
Member Since: Jun 2007
Location: Bel Air (by way of Fort Worth, TX) Maryland
Posts: 64,864
Received 1,660 Likes on 847 Posts
St. Jude Donor '12-'13-'14-'15-'16-'17-'18-'19-'20-'21


Default

Originally Posted by rkrupka
Do they add catch cans on the cars at the Ron Fellows school?
No. The cars are totally stock.

I might add that adding a catch can on an otherwise stock engine is at best unnecessary and at worst detrimental.

Last edited by Chemdawg99; 07-13-2022 at 08:13 AM. Reason: Grammar correction
The following 5 users liked this post by Chemdawg99:
hamta (07-13-2022), jackfrostpdx (07-12-2022), johnodrake (07-14-2022), M2Pilot (07-12-2022), rkrupka (07-13-2022)
Old 07-12-2022, 06:58 PM
  #12  
Avanti
Race Director
 
Avanti's Avatar
 
Member Since: Mar 2001
Location: Bonneville Salt Flats, 223mph Aug. '04
Posts: 17,518
Received 5,254 Likes on 3,483 Posts

Default

Do an "Advanced search" across ANY series Vette Forums here from at least the C5 on and you will find many, many threads touting or criticizing catch cans. If it were so simple and so great, not to mention remotely necessary, one would think by now (only my opinion as a life-long scientist) even GM... and, all the other manufacturers... would have figured it out.
The following 7 users liked this post by Avanti:
Chemdawg99 (07-12-2022), Floridasky (07-12-2022), hamta (07-13-2022), johnodrake (07-14-2022), RKCRLR (07-12-2022), rkrupka (07-13-2022), Zormecteon (07-12-2022) and 2 others liked this post. (Show less...)
Old 07-12-2022, 08:27 PM
  #13  
AzDave47
Race Director
Support Corvetteforum!
 
AzDave47's Avatar
 
Member Since: Feb 2011
Location: AZ
Posts: 13,276
Received 4,539 Likes on 2,614 Posts

Default

Per my post #5 above, I would say it is only necessary if you do road courses and run at a high level.
Old 07-12-2022, 09:59 PM
  #14  
Maxie2U
Le Mans Master
 
Maxie2U's Avatar
 
Member Since: Aug 2015
Location: Southwest Florida
Posts: 7,903
Received 4,255 Likes on 2,289 Posts
Default

I’m a big fan of UPR Products their CC design and quality is 2nd to no one. I had one installed on my C7 and it caught a lot of gunk and the outer tips never got black even after 6500 mile road trips. I installed UPR’s C8 CC right after I took delivery in April so time will tell if it’s needed on my C8.





The following users liked this post:
blkvett01 (07-13-2022)
Old 07-12-2022, 10:46 PM
  #15  
Vetteman Jack
Administrator

Support Corvetteforum!
 
Vetteman Jack's Avatar
 
Member Since: Mar 2001
Location: In a parallel universe. Currently own 2014 Stingray Coupe.
Posts: 343,561
Received 19,480 Likes on 14,071 Posts
C7 of the Year - Modified Finalist 2021
MO Events Coordinator
St. Jude Co-Organizer
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16-'17-'18-'19-
'20-'21-'22-'23-'24
NCM Sinkhole Donor
CI 5, 8 & 11 Veteran


Default

I had a catch can on my C5 and also have one on my C7. It does catch some oil in the can and I figure it keep the oil out of the intake. There are arguments for and against catch cans on the Corvettes - I simply chose to go with the catch can on my cars.
Old 07-12-2022, 11:45 PM
  #16  
4thC4at60
Le Mans Master

 
4thC4at60's Avatar
 
Member Since: Jun 2002
Location: Commerce Texas
Posts: 5,982
Received 2,944 Likes on 1,312 Posts

Default

Do AMG, McLaren, Ferrari, Lamborghini, and Pagani have catch cans?

Old 07-13-2022, 01:05 AM
  #17  
itsonlyairandfuel
Melting Slicks
 
itsonlyairandfuel's Avatar
 
Member Since: Jun 2001
Posts: 2,003
Received 390 Likes on 243 Posts

Default

Originally Posted by rkrupka
Do they add catch cans on the cars at the Ron Fellows school?
They sell them off before they get to 10,000 miles.
The following users liked this post:
SECLT22021 (07-13-2022)

Get notified of new replies

To C8 Catch Can Controversy

Old 07-13-2022, 05:04 AM
  #18  
Kingtal0n
Melting Slicks
 
Kingtal0n's Avatar
 
Member Since: Oct 2007
Location: South Florida
Posts: 3,259
Received 729 Likes on 501 Posts

Default

Originally Posted by vetteLT193
It may not need one but it won't hurt.
This is not always true. Moving air molecules costs energy. The energy has to come from somewhere.

if you add a longer line into the pcv system or additional volume, you add air molecules, now you need more energy to move more mass of air.

The increased demand for energy results with higher pressure, if the same energy is being input as before the added volume.

This increased pressure results with more oil being blown from an engine- the can volume causing oil to blow out of the engine, impacting PCV performance.

In other words: Just because you catch oil in the can, doesn't mean the oil would have been there without the can.

I am not against catch devices. But like most modifications, there is a right way and wrong way to do them.
In the case of catch cans, you MUST measure the crankcase pressure before, and after the installation, and then take steps to ensure the previous pressure inside the crankcase as before the install is being met.

Adding a catch can is like adding a fuel regulator or a supercharger or any other mod: you must set the pressure properly once install is complete.
If you install a new fuel regulator, you don't just blindly assume the fuel pressure is correct.
IF you install a supercharger, you don't blindly assume the boost pressure is correct.
If you install new tires, new oil pump, new transmission, you don't blindly assume the pressure is correct.

The same goes for catch can. You must measure crankcase pressure and set it after the install as with all other pressure scalar.
A catch device can assist with oil aspirate during a true thrashing on a track specific vehicle without appropriate dry sump system configuration, typically wet sump applications with inadequate drainage of the head for example, may require some type of can device, those are the rare situations where it may be helpful, and it must be installed properly as with all modifications.
The following 8 users liked this post by Kingtal0n:
65sohc (08-27-2023), elegant (07-13-2022), hamta (07-13-2022), Korbek (07-13-2022), RKCRLR (07-13-2022), Tim0shel (07-13-2022), Zormecteon (07-13-2022), Zymurgy (07-13-2022) and 3 others liked this post. (Show less...)
Old 07-13-2022, 07:25 AM
  #19  
rkrupka
Pro
 
rkrupka's Avatar
 
Member Since: Jan 2014
Posts: 584
Received 277 Likes on 175 Posts

Default

Originally Posted by itsonlyairandfuel
They sell them off before they get to 10,000 miles.
Yes, I know. But I doubt I could identify any other cars that would have been driven any harder for more miles.
Old 07-13-2022, 08:08 AM
  #20  
Andybump
Le Mans Master
 
Andybump's Avatar
 
Member Since: Mar 2007
Posts: 5,908
Received 3,851 Likes on 2,287 Posts

Default

Originally Posted by Shoal07
The GM engineers answered this in an interview a while back. The way their dry sump system works that oil would have made it back into the sump not the cylinders.
This is what I thought as well. But, I reviewed the crankcase ventilation description and circuits in the service manual, and the instructions for installing the UPR catch can, and its not clear why that statement is true. There are three separate "tubes" involved. 1) filtered fresh air is routed from upstream of the throttle plate through a formed nylon fresh air tube to PCV fittings in the left and right rocker arm covers. The rocker arm cover design shields rocker arm oil spray, to reduce the potential for oil being drawn back into the fresh air PCV tube during any backflow of the ventilation system. 2) Separated foul vapor from the engine oil tank is routed to PVC fittings in the left and right rocker arm covers via a formed nylon recirculation tube. 3) Foul crankcase vapor is routed through a formed nylon foul air tube on the engine oil separator in the engine valley to right side rear of the intake manifold. From the UPR instructions, the catch can is installed in this third path - the original tube is removed and replaced by a tube from the "engine valley" (essentially the crankcase) to the catch can, and another tube from the catch can to the right side of the intake manifold. It does not seem possible for any oil in this path to go anywhere other than to intake manifold, or the catch can if one is installed. So, in the context of the engineer's statement, this path must be completely free of oil. But with the catch can installed, oil is collected. The only thing I can think is the theory that without the catch can there is no oil in that path, and the presence of the catch can somehow changes the pressure in the line and allows oil to enter it. That seem questionable - if anything the extra tubing and catch can would reduce the flow though that line - why would that cause more oil to enter it? Did the engineers elaborate on their explanation of why "that oil would make its way back to the oil sump"?
The following users liked this post:
SECLT22021 (07-13-2022)


Quick Reply: C8 Catch Can Controversy



All times are GMT -4. The time now is 04:31 PM.