one eyed willy

I never saw if it was determined for sure if the 2017 had something factory installed already? Just picked up a 2017 grand sport this morning, have a UPR catch can I never installed. Saw a post a while back where it was thought 2017 wouldn't need a catch can.

PeteC7

Tadge answered this question but there is still some debate:
https://www.corvetteforum.com/forums...te-engine.html

I decided to leave it stock based on his response, the car is still under warranty, and I have a couple friends with high mileage C7's that didn't install one.

Red C8 of Jax

Left my 2015 stock, had some members of our corvette club install the catch can and when the catch can didn't collect any oil (or very little) they removed them.

dvilin

Not needed.

JerryU

I'll install the Elite Catch on my new Grand Sport that I took off of my 2014 Z51 when I sold it. I did post something about looked like they made a change in the 2017, which they did, you can see the new lines coming from the valve covers! However a poster pointed out and I quickly found the same small line going from the PCV valve to the intake manifold.

There is one line I am still looking for. Where do they get the clean filtered that must go into the crankcase when you're pulling air, blowby, burned oil particles that hit the hot pistons and other "stuff" out with the PCV system? They did eliminate the hose pulling air from the intake tube to the crackcase-still can't find where the clean air is coming from. Believe it's that same on the Z06. Anyone know where the clean air is coming from?

Want to know where that is before I install. Although I have a 2 exit can, I only use one outlet and the other is plugged. If I tracked might use two. Made it easy to remove my Elite Can as no holes drilled in the air intake. This is a PDF that has my install on my 2014 Z51. Explains why I only use one outlet and other info: http://netwelding.com/Catch_Can.pdf

Looks like the install for the Grand Sport will be easy and the same. Particularity note my use of a stud when mounting the can and being very careful about combining a chassis ground wire with the can attachment bracket! Several interesting posts where folks had the electric steering trip a code and several shut down! That motor pulls over 100 maps in a transient move and if you don't have a perfect ground it could be an issue!

They did eliminate the hose pulling air from the intake tube to the crackcase-still can't find where the clean air is coming from. Believe it's that same on the Z06. Anyone know where the clean air is coming from?

As far as need, not tracking I got about 1 ounce caught in the can per 1000 miles in my Z51, expect the same. Not a lot but better that ounce is dumped in the recycle center than baking on the back of the intake valves! Even the new Ford GT engine has DI plus port injection that like a Toyota engine that operates periodically and washes the back of the valves with gasoline as my C6 etc. Maybe the new mid engine Vette motor will have the same!

one eyed willy

Well I noticed on my 2017, things are routed differently and I'm missing a spot for one of the connections on the intake tube. So not sure what to do....

pbergmann

Save your money... not needed this has been beat to death...

JerryU

Hmm, if you want to use a second "can" outlet that goes to the intake air tube, you have to drill your own hole! If you have a supercharger or track (i.e. have a lot of driving with more than 90% throttle over a small time period) then that could be useful. However I don't and have the 2nd "can" outlet plugged. In my case they both come from the top sides of the can.

A similar short PVC hose as was on my 2014 Z51 is on my Grand Sport. That is what I will be replacing by inserting my now one outlet "can" in replace of that line and catch some of the crackcase blowby and "stuff" that comes from the PCV system. As with my 2014, expect I'll catch about 1 ounce/1000 miles. Better in the can and discarded than baked on the back of the intake valves!. The line looks somewhat different but goes from a PCV valve to the intake manifold and is in about the same location.

The only thing missing on my intake tube is NOT a line from the "can" it's the OEM line that took filtered air from the intake tube into the crackcase. I'm still looking for the engines new source of filtered air!

Motors5

I have a 2017 Stingray Z51.


I opened my intake at 2000 miles to have a look and there were not a drop of oil. completely dry. Yes only 2000 miles but anyway.


There is a change in the engine bay from 2016 where they in 2017 take one of the lines from the engine (the one passing over the throttle body in the picture below) directly to the dry sump tank. I guess they use the dry sump tank as a catch can (Smart!!!). After all it is just used engine oil and as long as you do the oil changes I would not worry! I prefer this to oil in throttle body and baked valves:-)


It is the same in the GS.

//Motors5

rtkelly

i've had my UPR catch can on for only about 400 miles. removed it the other night to see if there was actually any build up or if i should just resell it. to my surprise I had a little bit of oil build up already. about 1/5th of a shot glass worth of oil already.

I got mine very cheap, and plan on keeping the car for a while.... it doesn't hurt, so whatever..... at least for the negligible price i paid.

one eyed willy

I have UPR dry sump can, bought it for the 2016 z51. The 2017 is routed differently and I remember talk of the new plumbing basically was the equivalent of GM adding their own can to the dry dump tank.

At this point I'm trying to decide on what to do with the one I have now.

djnice

On my 2017 GS, I used an old RX can from my Camaro and it works fine. It does catch less oil than the Camaro, but still worth it.

GM's hose routing is not equivalent to a can. There is still a route from the crank case to the intake manifold.

On the drivers side just behind the throttle body you will see hose from the valley cover to the intake. There is a check valve in the valley cover hose barb. This hose does get wet with oil. That's where you intercept the flow and put it through your can.

Here is a photo, my can is also vented. Don't worry about that part.

David@MMS

there is no factory installed can, but the dry sump can sometimes help, and sometimes hurt the problem (that still exists).

remove your throttle body and look behind it. if you don't like what you see then you are in the market for a catch can same for the cold air intake tube.

If there are any specific questions to c7 pcv hose routing I am happy to answer.

-in response to JerryU, pcv fresh air supply comes from the cold air tube after first being measured by the MAF sensor, and then enters either the passenger valve cover, or the forward port of the oil tank (if dry sump).

rtkelly

abc

rb185afm

I ran my car at Buttonwillow for two days. After that plus 4K miles of driving, almost no oill! Looks like the 17 Grandsport system is working pretty well.

JerryU

Thanks. However what you describe is what I had on my 2014 C7 Z51. Where the dry sump burped air came into the air intake tube, there was another hose barb and hose. It took clean air as you describe and put it back in the crackcase so the PCV system had a source of air.

On the Grand Sport there is only one hose barb and hose in the air inlet tube after the filter and MAF. It is the one coming from the dry sump tank for burped air (and whatever other vapor, oil foam or oil if overfilled.). That second line is not there. ???

David@MMS

original lt1 stingray had two hoses, the revised as posted on the GS above is now standard on all dry sump c7'z. it does a better job at oil control diverting both valve covers first to the dry sump tank. so there is only one cold air tube line.
(dark green line here)


i would still check the cold air tube after any road racing for liquid oil build up blown out of the dry sump tank. the line from valley to intake manifold is only half of the system.

JerryU

David, afraid I still don't understand where the clean air is coming from that goes to the crackcase?

To have crankcase "stuff" flow through the PCV system, air must enter the crackcase. In my 2014 Z51 that air came from the intake air tube through a hose barb and hose. Where is the source in the Grand Sport that does not have that barb and hose?

PS: Even for the 8.2 Liter engine in my Street Rod I tapped the base of my 14 inch diameter air cleaner for the clean air that goes though a hose into one valve cover and the PCV valve comes from the other valve cover through a hose that connects to below the Holley 850 double pumper.

djnice

Dave, there is one hose you didn't identify. It is on the right side of your blue line. What is that hose for?

Jerry, doesn't fresh air go in the green line to the oil tank and then from there thru either the blue line or yellow line to the valve covers?

David@MMS

air goes into the oil tank, and then from the oil tank to the valve cover(s). it is just like any other pcv system only there is an oil tank in between fresh air and the valve covers. this is nearly identical to c6 dry sump with the revision
my c6 dry sump stock system diagram for example


that is fumes control line to the gas tank (EVAP system)