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Double-Duty Daily Driver (Ď03 Z06 Build Thread)

 
Old 03-26-2019, 12:02 PM
  #21  
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Default Stay Focused!

Thereís nothing like a deadline to bring a plan into focus. I have my first track outing next Wednesday at AMP, so I need a realistic punch list for what to accomplish before then.

Pressing Issues:
  • Basic maintenance
  • Wheels / Tires
  • Excessive oil in catch can
  • Oily engine compartment
  • Ride Height / Alignment

Basic Maintenance
For next week my primary goal is to not die, so brake fluid is high on my list. Since Iíll already have the car in the air I think Iíll go ahead and change the oil, which may be a couple years old by now.

Before I can do any of that I need to be able to get under the car. I spent a good part of last Saturday making a trip to Harbor Freight for a new jack (my old one was way too tall) and building some ramps out of 2X10s.


My first-ever Harbor Freight purchase.

Once I had the ramps and the jack, I ran into an issue where the car would push the ramps instead of riding up onto them. So I found a can of plastidip and sprayed the underside of the ramps to add a bit of friction. The thought did not occur to me that I could try backing onto the ramps instead, which has the added benefit of avoiding the factory front chin spoiler, which in my case rides very low.


Struggling to get it onto my ramps.

At @Kubs recommendation, I signed up with Amsoil and have a couple gallons of 10W40 and a few bottle of their Dominator brake fluid. I also picked up a Motive power bleeder kit and some ESCO jack stands.

Most of the stuff should arrive tomorrow, which will give me plenty of time to bleed the brakes and change the oil. I havenít decided whether to go after stainless brake lines at this stage, Iím a little worried about botching something and not having time to fix it before Wednesday.

Wheels / Tires
This arguably should have been a very low priority but as I said earlier I really donít care for the wheels that came with the car. I was planning on a square set of Forgestars with Michelin PSS, but that would be ~2 months out and would run close to $3K for the setup. Plus I wasnít 100% convinced on my tire choice.

As luck would have it, a set of black powder-coated forged Alcoa factory wheels showed up in the classified section on Saturday and they happened to be local. They also included a set of Toyo R888Rs that still have a fair bit of meat left on them (2017 date code).

As Macklemore would say, ďEight hundred cash, thatís a hell of a deal!Ē Seller is a nice guy who tracks his Z06, so I imagine Iíll run into him again.


+50% grip, +1,000% looks.

I picked up those bad boys on Sunday morning and threw them on the car. Took her for a drive and it was a huge improvement in grip and feel, not to mention looks. These tires have enough life left to give me time to think about my options.

Excessive oil in catch can
To get a better what was going on in my previous post, I emptied the catch can, noted the mileage, and took the car on my trip to Harbor Freight. Also got around to taking my wife for a spirited drive, she really likes the car.

After 85 miles that included some pretty aggressive driving, I checked the can again. This time I measured what was in it - about 60 ml. That works out to a quart every 1,365 miles or filling the 11 oz capacity every 467 miles.


85 milesí worth of oil.

Iíd love to hear thoughts on this but after doing a lot more reading over the weekend Iím less freaked out than I was originally. It seems like guys are all over the place in terms of how much oil they find, and a lot of times it has to do with the setup of the system, which I havenít taken any time to familiarize myself with.

Bottom line is Iíll empty it every time I fill up at the pump and before any track excursions. If Iím able to check it between sessions (and have a place to dump it) Iíll do so, but Iím wondering how people accomplish this when the engine is fully up to temperature becauseÖ itís very hot.

A longer term goal will be to troubleshoot this further and hopefully resolve it.

Oily engine compartment
The current working theory is that Iíve got a leaking crank seal, which may be due to lack of a harmonic balancer to go with my mystery camshaft. This is not something I feel confident in tackling over the course of the coming week so my short-term plan is to clean up as much of the oil and grime as I can before I go to the track. This should also help determine where the oil is coming from.


The bottom of the pan is covered in a film of oil.


Another shot of the pan.

Ride Height / Alignment
I think the car looks great as-is but it scrapes like crazy and I donít believe we get the best handling from these cars when the stock bolts are lowered as much as possible (which is where mine are).

My plan is to raise it back closer to stock ride height and then find a place to take it for an alignment. If anyone has a recommendation on that front Iíd appreciate it.

I havenít researched this process at all yet so I donít know if itís a quick job once the car is in the air, but Iíll assume that it is.


Iíll report back in a few days with progress. Thanks again for all of the insight and suggestions, Iíve already learned a lot.
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Old 03-26-2019, 02:38 PM
  #22  
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Ok, I'll preface this by saying I'm not an expert engine builder, so take what I say with a grain of salt.

IMO that is a lot of oil in the catch can for just driving on the street.....and the issue is it is very much just oil and no other contaminates (at least it looks like all engine oil to me). On my other cars with a catch can I get a oil/watery moister mixture. On my C5 Z06 I do an entire track day (minimum 300-ish miles) and get about a quarter of what you did.

Regarding your modified engine, I am ALWAYS suspect of an engine that has been cracked open and modified by somebody that I don't have control over. There are just too many variables that can be iffy from parts to assembly. Without knowing the exact parts used and who did the machining and or assembly, it really is a crap shoot. Just start a little slush fund to cover you if something goes pop. I've seen a lot of incorrectly modified cars fail within 3k to 5k miles of the engine being "built". It is way more common than uncommon when buying somebody else's build that you didn't have control over. Like I said, just my opinion based on many years of past experience (and seeing a ton of friends who thought they bought a great modified car end up being very disappointed).

Case in point, what engine builder or car owner would do a build and allow that kind of oil leakage?......that's been there for a while and it is leaking a lot.
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Old 03-26-2019, 03:17 PM
  #23  
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Originally Posted by TrackAire View Post
Ok, I'll preface this by saying I'm not an expert engine builder, so take what I say with a grain of salt.

IMO that is a lot of oil in the catch can for just driving on the street.....and the issue is it is very much just oil and no other contaminates (at least it looks like all engine oil to me). On my other cars with a catch can I get a oil/watery moister mixture. On my C5 Z06 I do an entire track day (minimum 300-ish miles) and get about a quarter of what you did.

Regarding your modified engine, I am ALWAYS suspect of an engine that has been cracked open and modified by somebody that I don't have control over. There are just too many variables that can be iffy from parts to assembly. Without knowing the exact parts used and who did the machining and or assembly, it really is a crap shoot. Just start a little slush fund to cover you if something goes pop. I've seen a lot of incorrectly modified cars fail within 3k to 5k miles of the engine being "built". It is way more common than uncommon when buying somebody else's build that you didn't have control over. Like I said, just my opinion based on many years of past experience (and seeing a ton of friends who thought they bought a great modified car end up being very disappointed).

Case in point, what engine builder or car owner would do a build and allow that kind of oil leakage?......that's been there for a while and it is leaking a lot.
Yeah I'm definitely concerned but I'm trying to compartmentalize the individual issues and not jump to conclusions.

There is definitely a lot of oil that has leaked over time but I suspect it's accumulated over the course of the previous owner's entire ownership of the car, which was a little over two years and about 1,500 miles. In a week I put as many miles on it as he did in 9 months. The amount that has dripped on my floor is tiny, maybe 10 literal drops.

The current working theory of a leaking crank seal seems plausible to me and if that turns out to be the issue it's really not a big deal.

The catch can does strike me as being more serious concern, which reminds me that I meant to post a picture of the setup:


The reading I've done so far makes this seem like a bit of a dark art - some guys experience little to no accumulation and others don't even bother emptying at the track because it fills up so fast. I'm not sure how much has to do with how the setup was plumbed vs. the characteristics of the individual motor in question. I'll keep digging around to see what I can find.

According to the seller, and verified at least anecdotally by an independent source, the car was built/tuned by a nationally-recognized shop, so I'm going to continue assuming that the work was done well with quality parts and an eye toward road-racing reliability. That said, I'm preparing myself for the possibility that something could go horribly wrong

Last edited by 911tt; 03-26-2019 at 03:18 PM.
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Old 03-26-2019, 04:01 PM
  #24  
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Can you post pictures to where the other ends of the catch can hoses go? That hose with a filter on the end (off the valve cover) is supposed to be feeding the catch can...
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Old 03-26-2019, 04:26 PM
  #25  
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The new wheel and tire combo look awesome on the car! One word of caution, R compounds are not really for track day beginners so don't push the car too hard just yet on the track. Street tires are often the way to go for people new at track days because they will give warning signs before losing grip where as the R compounds will not.

That looks like a whole lot of oil in the catch can for only 85 miles at least compared to what I'm seeing with my car I'm not quite sure what that means but I wouldn't panic until everything is gone through and vetted first. I didn't read all the posts so my bad if this was already mentioned I'd start by double checking the routing of the lines, the correct routing is on page 6: http://www.eliteengineeringusa.com/t...uctions_CC.pdf

I'd also check to ensure that the PCV valve is 1. facing the correct direction and 2. not clogged. Remove the PCV valve and make sure it jingles freely. Clean it out good and reinstall. I think that's a good start. Good luck!
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Old 03-26-2019, 04:26 PM
  #26  
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Originally Posted by Kubs View Post
Can you post pictures to where the other ends of the catch can hoses go? That hose with a filter on the end (off the valve cover) is supposed to be feeding the catch can...
Sorry, this one shows the routing of the hoses better:
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Old 03-26-2019, 04:29 PM
  #27  
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Originally Posted by Kubs View Post
Can you post pictures to where the other ends of the catch can hoses go? That hose with a filter on the end (off the valve cover) is supposed to be feeding the catch can...
That guy (fresh air line) is supposed to enter the intake air stream not the catch can. If he had a stock LS6 TB the line would connect directly to the TB itself. With the LS2 TB he has, the line would go anywhere in the intake tract after the MAF and before the TB. Given that it is vented with a filter, I think it's ok as-is tho.

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Old 03-26-2019, 04:30 PM
  #28  
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Originally Posted by 911tt View Post
Sorry, this one shows the routing of the hoses better:
Routing into and out of the catch can is correct. I do not see a PCV valve in there where it should be (for a 2003 C5Z) which is between the intake manifold and catch can. In 2004, the C5Z got an internal pcv valve/oriface restricter thing whatever it really is which was installed in the tube coming out of the valley cover. Pop that line off coming from the valley cover and see if there's any restricter oriface inside like on an '04. Since you have an '03, your PVC valve is supposed to be located as seen below:



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Old 03-26-2019, 04:49 PM
  #29  
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Originally Posted by wrkdWS6 View Post
Routing into and out of the catch can is correct. I do not see a PCV valve in there where it should be (for a 2003 C5Z) which is between the intake manifold and catch can.
I was just noticing the same thing. Since the valve cover is vented I assume the PCV valve was omitted intentionally?
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Old 03-26-2019, 04:55 PM
  #30  
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Originally Posted by 911tt View Post
I was just noticing the same thing. Since the valve cover is vented I assume the PCV valve was omitted intentionally?
Hmm Iím not sure.

If the line coming out from the valley cover (hard line that comes out from under the intake manifold) does not have anything inside of it, I would put a PCV valve on the car just as it should have it between the the catch can to intake manifold connection. Iíd also toss out the breather and run a line from there to between the MAF and TB where it should be. Then I would see if that changes the levels your seeing in the catch can. Just my .02. Plenty of people run breathers but you may get an oily valve cover after a track day so I prefer the intended routing especially when diagnosing a problem.

I wish I had my car handy because I also have an '03 and have that same catch can and LS2 TB etc. and would take a pic of how the whole deal should look. When I get home from work here i will see if I have any pics on my computer that would help you out.

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Old 03-26-2019, 05:37 PM
  #31  
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Originally Posted by wrkdWS6 View Post
Pop that line off coming from the valley cover and see if there's any restricter oriface inside like on an '04.
I took that line off and there's no restriction in it. Just a plain piece of hose.
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Old 03-26-2019, 06:23 PM
  #32  
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Originally Posted by 911tt View Post
I took that line off and there's no restriction in it. Just a plain piece of hose.
Check out post #10:
https://ls1tech.com/forums/generatio...catch-can.html

Various posts here state the same:
https://ls1tech.com/forums/generatio...thout-pcv.html

I think we found the smoking gun

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Old 03-26-2019, 06:47 PM
  #33  
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Originally Posted by wrkdWS6 View Post
I think we found the smoking gun
Great find! He makes a convincing argument. Also, without a PCV there could be excess pressure that could lead to oil leaks (unless the gasket cover breather prevents it). I'll go ahead and order a PCV to put in-line with the existing system to see what happens.

Edit: My setup is less restrictive than a factory PCV setup, not more. So pressure is not my problem.

Last edited by 911tt; 03-26-2019 at 07:45 PM.
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Old 03-27-2019, 08:59 AM
  #34  
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I spent 3-4 hours reading last night and I think I'm starting to wrap my head around these PCV / catch can setups.

I ordered two PCV valves. One was $6 on Amazon: Beck Arnley 045-0299. It appears to be an orifice-style "valve," meaning it simply narrows the hose to restrict flow. It doesn't have any kind of spring-loaded mechanism that would stop flow altogether, and will allow flow in either direction. It will fit inline with a 3/8" hose (which is what I have) and I saw that some other LS guys have used it. This will be added to the line that runs from the catch can exit to the intake manifold. The catch can is being fed from the valley cover. We position the PCV valve after the catch can so that it doesn't get oil running through it, which could gunk it up. The theory is that by restricting the flow from the valley cover to the manifold, we'll retain the ability to vent the pressure that builds up in the motor but we won't see as much flow as we do in my unrestricted setup, which should reduce the rate at which the catch can fills.

I also ordered a fancy Elite Engineering 10mm machined aluminum one-way check valve (CV-375) for about $40. I'm not sure if this will arrive in time to try it before next week's track event, which is why I ordered both valves. It's a little different from the orifice-style valve in that it wont allow flow backwards from the intake manifold (which I don't think is a major concern anyway). It will be fun to A-B test the two different valves. Given how much oil I'm currently collecting in my catch can, it will be easy to measure an improvement if there is one.

Based on my reading, the breather component of the system is just as important as the PCV valve.

I have a simple breather tube with a small filter attached to the passenger side valve cover. The goal of the breather is to allow clean air to flow into the crankcase, which is required as part of the PCV operation. If I understand it correctly, the PCV line uses intake manifold vacuum to suck clean air through the breather. The mixture of clean air and oily vapor is then routed via the PCV valve back into front of the intake manifold. At WOT there isn't enough vacuum in the manifold for this to happen, so excess crankcase pressure is instead vented through the breather. With an LS motor, under certain conditions like a sustained high-G turn, the valve cover can accumulate a lot of oil, which, combined with the pressure from the crankcase, gets pushed through the breather tube.

With a stock setup, this oil would actually travel all the way to the throttle body and make a nice mess all over your MAF, intake, etc. My LS2 throttle body doesn't have a provision for this line to attach, so the oil would simply get forced through the filter and spewed all over the engine bay. That doesn't appear to have ever happened with this car, but that could be because it's never been driven under conditions where the valve cover had a lot of oil in it. I guess we'll find out next week at my track event.

There are a couple different methods for avoiding the breather burping oil directly into the engine bay or back into the intake. Some guys block off the valve cover vent tube and use a vented oil fill cap, the theory being that the oil cap is situated higher up and therefore less likely to have oil make its way all the way out. A further solution is to add a catch can that can collect that oil. The catch can could be fed directly from the atmosphere or routed to a new bung in the intake (aft of the filter).

I'm still a little hazy on the interplay between the breather and the PCV valve in general as well as the unique aspects of the LS design, but I'm enjoying learning about this stuff. Hopefully this weekend I'll be able to install a valve and determine whether it makes any difference when it comes to street driving.
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Old 03-27-2019, 03:53 PM
  #35  
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I think what you purchased should do the trick for you. If you get anything spewing out of that filter on the vent line then just run the line into the intake bellows piece and that will solve that issue but who knows you may be ok as-is. Have fun at the TNIA event, I love going to those and have one coming up myself. Just remember that it isn't a race, go at whatever pace you are comfortable with. Don't worry if slower cars are up your tail and want to pass just wave them on by. You will have a blast, even a stock C5Z is a beast of a track car.
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Old 03-27-2019, 04:24 PM
  #36  
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Originally Posted by wrkdWS6 View Post
I think what you purchased should do the trick for you. If you get anything spewing out of that filter on the vent line then just run the line into the intake bellows piece and that will solve that issue but who knows you may be ok as-is. Have fun at the TNIA event, I love going to those and have one coming up myself. Just remember that it isn't a race, go at whatever pace you are comfortable with. Don't worry if slower cars are up your tail and want to pass just wave them on by. You will have a blast, even a stock C5Z is a beast of a track car.
Thanks, I appreciate your assistance with trouble-shooting this thing. I'm really excited to take it out to the track. I tend to be a cautious driver anyway, so my goal is to just get a better feel for the car, a sense of the track layout, learn some track etiquette, and have a good time.

The new jack stands are arriving today so I'll be trying to get the car off the ground and see if I can get the underside of the engine area cleaned up a bit and assess where the oil might be coming from.
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Old 03-28-2019, 10:15 PM
  #37  
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Default Beneath the Beast

New jackstands arrived yesterday so I was able to jack her high enough to get underneath. For what itís worth, this is my jacking procedure:
  1. Place jacking pucks in all four locations
  2. Back the front wheels onto ramps made of two stacked 2x10s
  3. Jack the back up high enough to place scrap 2x10s under the rear tires (if I donít do this before jacking the front all the way up I donít have enough room under the rear)
  4. Chock the rear wheels
  5. Place an 18Ē 2x10 on the jack, jack the front cradle just about as high as the jack allows
  6. Lower the front onto the jack stands
  7. Place an 18Ē 2x10 on the jack, jack the rear all the way up
  8. Lower the rear onto jack stands
  9. Give the car a few shoves to make sure it doesnít want to go anywhere
  10. For added safety I placed jack stands below the front and rear cradles
  11. Then I removed the wheels for extra room
The result:

So much room for activities!

My primary goal tonight was to get as much of the oily muck wiped away as I could in order to get a better idea of where my oil leak is coming from. This was accomplished with half a roll of paper towels, some Simple Green, and some shop towels.

As we saw earlier, the top of the front leaf spring was absolutely coated with an oil-dirt mixture. The entire bottom of the oil pan was also covered in a film of oil, which I believe was being picked up by airflow as it dripped from the leaf spring.

Iím hoping that by getting it cleaned up Iíll be able to see more clearly where the leak is coming from.

So here are a few things that I discovered:

Steering shaft is very oily both inside and outside the shroud.


There is a lot of fresh-looking oil on the bottom of the AC compressor and pulley.

Some additional pics of that area:





My front sway bar is contacting the driverís side lower control arm. Thatís bad right? Maybe that explains why I keep hearing clunking and banging? I thought it was coming from the back of the car. Passenger side has quite a bit of clearance.


I tried to get a better view of the crankshaft pulley area, as there was speculation that the front crankshaft seal could be the leak culprit. The area has its share of sludge, but it didnít appear wet to me:






Tomorrow Iíll try running it a bit to see if any fresh oil appears.

If those pictures give you experts out there any ideas about where my leak may be coming from, Iíd love to hear about it. Probably worth noting that I canít see any leak source near the back of the engine, it all seems to be down low and up front, right above the leaf spring.

Also on the agenda tomorrow:

  • Brake fluid
  • Motor oil
  • Adding a PCV valve
  • Maybe raising the springs a bit (theyíre max low at the moment)
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Old 03-29-2019, 01:36 AM
  #38  
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Disclaimer first: I haven't actually done this to my car yet, but it's near the top of my to-do list.

Consider putting the check valve between the valve cover and the little air filter, so that it only allows air to enter the head from the filter. Manifold vacuum will pull the valve open at low throttle. At high throttle, the check valve will close, and blow-by fumes will flow through the catch can and into the intake manifold, propelled only by the blow-by. That way, 100% of what flows out of the crankcase will also flow through the catch-can. I like the idea of watching for changes in catch-can fill rate for signs of trouble. Opinions differ about the wisdom of pulling blow-by into the intake manifold (even with a catch can) but I think the risks are overrated.

I also bought a C5 for track days. Haven't had it on track yet but that should change in a few weeks.
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Old 03-29-2019, 07:18 AM
  #39  
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Originally Posted by NSFW View Post
Disclaimer first: I haven't actually done this to my car yet, but it's near the top of my to-do list.

Consider putting the check valve between the valve cover and the little air filter, so that it only allows air to enter the head from the filter. Manifold vacuum will pull the valve open at low throttle. At high throttle, the check valve will close, and blow-by fumes will flow through the catch can and into the intake manifold, propelled only by the blow-by. That way, 100% of what flows out of the crankcase will also flow through the catch-can. I like the idea of watching for changes in catch-can fill rate for signs of trouble. Opinions differ about the wisdom of pulling blow-by into the intake manifold (even with a catch can) but I think the risks are overrated.

I also bought a C5 for track days. Haven't had it on track yet but that should change in a few weeks.
At one point I was thinking about placing a check valve in front of the breather filter so that the breather can only pull air into the valve cover and no oil can come back out the other direction. After all, pulling clean air into the crankcase is the breather's only role, right? The reason I initially rejected the idea is because it seems the breather is designed to work both ways, sometimes allowing gas to exit, especially when the manifold isn't generating vacuum, i.e. WOT. That concept makes some degree of sense, but if pressure does build up in the crankcase, I'd expect it to vent through the valley into the PCV valve, so now I'm confused.

Your suggestion got me to do some additional reading. This site has an interesting write-up: https://www.aa1car.com/library/pcv.htm that I think is better than Wikipedia's description.

The key piece that I was missing before is that with a typical spring-loaded PCV valve, the valve is fully open under decel, but being fully open actually provides minimum flow, which is good because there's very little need to vent crankcase pressure, so you don't want to be actively sucking oily air out of the crankcase and back into your manifold if you don't have to. Under WOT, the valve is partially closed due to lack of vacuum, but this actually provides maximum flow. Again, this is what you want because WOT is where you see maximum pressure and the whole point of the system is to keep the crankcase from pressurizing. When the car is off, the valve fully closes because nothing is acting against the spring.

My thinking is that under WOT, if enough pressure builds in the crankcase, the PCV valve could be pushed to its fully open position, which would then minimize its ability to flow and release pressure. That's where the breather comes into play. Under WOT the breather provides an additional pathway for pressure to dissipate.

So I don't imagine you'd want to put a check valve on the breather because that would prevent it from providing additional emergency venting from the crankcase when needed.

If you're suggesting putting the check valve at the breather instead of between the valley and the manifold, that seems like a bad idea because (in theory) the reason I'm getting so much oil in my catch can is because of my lack of PCV valve (I really love using italics to emphasize words). Again, the lack of PCV valve means that under decel, the manifold vacuum is completely unchecked and I'm pulling a huge volume of oily air through my catch can under conditions where there is no crankcase pressure to vent. It's a wasted effort.

What this doesn't explain is why the 2004 Z06 (and later cars from what I understand) switched to an orifice-style valve. The orifice would lose the ability to regulate airflow based on driving conditions, instead it would just limit maximum airflow. Maybe the spring-loaded PCV valves are prone to getting stuck, which would cause all sorts of problems, especially if they were stuck closed. If you're running a catch can setup that would be much less likely to happen because the air coming out of the catch can should be much cleaner than what went in.

A few days ago I had no idea what a PCV system was, so take this with a grain of salt, but this would be my summary:
  • A PCV valve between the valley and the front of the manifold is necessary because it intelligently regulates flow from the crankcase back to the manifold to avoid excess airflow, which is probably why my catch can fills so fast without one.
  • The breather should not be restricted with a valve because it needs to flow both ways, just in case the PCV valve is ever overwhelmed by crankcase pressure.
Assuming I'm right, the best method for dealing with an oily breather situation would be a second catch can positioned between the valve cover vent and the breather filter. With a second catch can I would feel better about routing the breather all the way to the air intake since there would no longer be danger of feeding oil directly into the intake and gumming up the MAF sensor.
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Old 03-29-2019, 09:57 AM
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1. Get dual cans and put a can on that fresh air feed line in the VC. You can't have the PCV going to the manifold and the fresh air on a breather. You're pulling unmetered air into the engine. Air goes in through breather cone, down into sump, out valley cover, then into manifold and MAF never reads it. (http://www.saikoumichi.com/Stage1_LS1_page.html)

2. Your leak up front could be from a few different things. If the timing cover was installed off-center when torqued it will wear the front main in short order. The "old school" way was to leave the cover loose until you insall the balancer allowing it to self-center and then torque. Or, if you have an ATI pin kit the hub is the perfect tool to center the timing cover as it's the same size as the balancer hub. I'd do a new timing cover gasket, new front main seal, and an ATI super damper. Get the 10% underdrive steel hub. 25% exists, but many thing it's too small to provide sufficient crank harmonics damping for a track car; OK for drag race.

Check out www.ls1howto.com and see their heads/cam swap and it has great step by step instructions with pics for working on these motors. I didn't know much about cars when I bought my first C5 in 2003, but by 2004 I did my own cam successfully thanks to that web site and have been racing/tracking these cars since.

Heads/Cam tutorial - http://www.ls1howto.com/index.php?article=1

Last edited by Tool Hoarder; 03-29-2019 at 09:59 AM.
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