RX Catch Can Install Question - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Camarotobeornottobe · 03-05-2015, 12:02 PM

For those with the RX single valve catch can . . .

Mine came a couple days ago, and it looks great. I upgraded to the black nylon lines with black ANS fittings.

My question is this: There is a check valve in the outlet side (the side going from the outside connection on the can to the intake), about six inches from the can. Is that valve necessary?

The valve obviously stops air from returning from the intake to the can. But, it is also offering some resistance coming from the can, i.e. it doesn't flow as free as if there was no valve. Since it had no such valve in the OEM setup to prevent or restrict flow anyway, why is it needed here?

I called RX, and their service was great. Out of an abundance of caution, they are sending a new check valve. But, he was also insistent that the valve was necessary and I really didn't understand his explanation as to why.

Thanks for the insight.

JDP Sales · 03-05-2015, 12:32 PM

On a N/A application you do not need check valves. Check valves are only needed for Centrifugal S/C or turbo applications where the manifold will fluctuate between boost and vacuum.

Best regards,

Tyler
888-308-6007

Camarotobeornottobe · 03-05-2015, 01:01 PM

Thanks. That is kind of what I thought. So, why would they include it for a single valve can? Obviously, it costs them money, so they must feel it necessary, right?

JDP Sales · 03-05-2015, 01:04 PM

Quote:

Originally Posted by Camarotobeornottobe

Thanks. That is kind of what I thought. So, why would they include it for a single valve can? Obviously, it costs them money, so they must feel it necessary, right?

Likely to be a universal fit. Having the CV should not hurt anything unless it's really restricting flow.

Best regards,

Tyler
888-308-6007

Camarotobeornottobe · 03-05-2015, 01:11 PM

Thanks again.

So, forgive my paranoia, but I want to be absolutely sure: For my otherwise stock LS3, there is no downside to removing the check valve and just running the outlet side of the can straight to the intake?

I read in an older thread that the valve also "regulated" flow to ensure the gases didn't flow too fast for the separator to do its job. However, I also read where valve getting stuck or restricted caused problems because of pressure build up.

So, just trying to figure out what's the safest way to go . . .

JDP Sales · 03-05-2015, 01:19 PM

The OE line does not have a CV, so why would you need one? The Elite Engineering cans do not have CVs either, but they are an option for boosted applications. I see no reason to have one.

Best regards,

Tyler
888-308-6007

Camarotobeornottobe · 03-05-2015, 04:15 PM

Tyler, thanks so much.

Has anyone else here taken the time to remove the valve?

Camarotobeornottobe · 03-06-2015, 11:41 AM

Okay, so one last question -- I need to remove the hose line with the check valve and reuse the ANS fitting to which it is attached. Can that be done by unscrewing the fitting and then cutting/pulling the hose off, or are the ANS fittings one and done?

03-05-2015, 12:02 PM	#1
Camarotobeornottobe Drives: 1LE Join Date: Feb 2013 Location: East Coast Man Posts: 550	RX Catch Can Install Question For those with the RX single valve catch can . . . Mine came a couple days ago, and it looks great. I upgraded to the black nylon lines with black ANS fittings. My question is this: There is a check valve in the outlet side (the side going from the outside connection on the can to the intake), about six inches from the can. Is that valve necessary? The valve obviously stops air from returning from the intake to the can. But, it is also offering some resistance coming from the can, i.e. it doesn't flow as free as if there was no valve. Since it had no such valve in the OEM setup to prevent or restrict flow anyway, why is it needed here? I called RX, and their service was great. Out of an abundance of caution, they are sending a new check valve. But, he was also insistent that the valve was necessary and I really didn't understand his explanation as to why. Thanks for the insight.

03-05-2015, 12:32 PM	#2
JDP Sales Drives: Chevys at the limit Join Date: Nov 2010 Location: SLC, UT Posts: 9,621	On a N/A application you do not need check valves. Check valves are only needed for Centrifugal S/C or turbo applications where the manifold will fluctuate between boost and vacuum. Best regards, Tyler 888-308-6007

03-05-2015, 01:01 PM	#3
Camarotobeornottobe Drives: 1LE Join Date: Feb 2013 Location: East Coast Man Posts: 550	Thanks. That is kind of what I thought. So, why would they include it for a single valve can? Obviously, it costs them money, so they must feel it necessary, right?

03-05-2015, 01:11 PM	#5
Camarotobeornottobe Drives: 1LE Join Date: Feb 2013 Location: East Coast Man Posts: 550	Thanks again. So, forgive my paranoia, but I want to be absolutely sure: For my otherwise stock LS3, there is no downside to removing the check valve and just running the outlet side of the can straight to the intake? I read in an older thread that the valve also "regulated" flow to ensure the gases didn't flow too fast for the separator to do its job. However, I also read where valve getting stuck or restricted caused problems because of pressure build up. So, just trying to figure out what's the safest way to go . . .

03-05-2015, 01:19 PM	#6
JDP Sales Drives: Chevys at the limit Join Date: Nov 2010 Location: SLC, UT Posts: 9,621	The OE line does not have a CV, so why would you need one? The Elite Engineering cans do not have CVs either, but they are an option for boosted applications. I see no reason to have one. Best regards, Tyler 888-308-6007

03-05-2015, 04:15 PM	#7
Camarotobeornottobe Drives: 1LE Join Date: Feb 2013 Location: East Coast Man Posts: 550	Tyler, thanks so much. Has anyone else here taken the time to remove the valve?

03-06-2015, 11:41 AM	#8
Camarotobeornottobe Drives: 1LE Join Date: Feb 2013 Location: East Coast Man Posts: 550	Okay, so one last question -- I need to remove the hose line with the check valve and reuse the ANS fitting to which it is attached. Can that be done by unscrewing the fitting and then cutting/pulling the hose off, or are the ANS fittings one and done?