When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hi, I believe my engine developed a front main seal leak but I think it only happens when under boost. I noticed a little residue about a week ago so I cleaned it and I have been taking it really easy since it's cold here. Yesterday I got on it a couple of times and when I got home I was changing a bumper extension when I looked and saw it was actually more wet than the last time and it looked fresh too. So my question is what are my options for a better vent system?
I have the ecs valve cover breather, the hose running to the sc filter on the passenger valve cover like ecs instructs and a catch can from the valley cover to the intake using a check valve. Attached is a picture for reference. I was thinking running a hose from the driver's side valve cover and connecting to the same line going to the sc filter. Any suggestions?
You can add a breather to the DS rear valve cover, there should be a plug in the hole from the factory. Personally I would never connect any PCV hoses back to the intake stream, but that's just me. I just connect the valley pan nipple to the PS side valve cover, cap the TB nipple, then run the cap breather. I've done this on both my GTO and Vette with no issues.
You can add a breather to the DS rear valve cover, there should be a plug in the hole from the factory. Personally I would never connect any PCV hoses back to the intake stream, but that's just me. I just connect the valley pan nipple to the PS side valve cover, cap the TB nipple, then run the cap breather. I've done this on both my GTO and Vette with no issues.
I see where than can work on an n/a engine but I don't see where this can help when the engine is pressurized and needs help to evacuate that extra pressure.
So I ordered a mighty mouse catch can and after reading a couple of posts from the can builder I decided to change the way I have the connections. First, I'm going to replace the current catch (elite engineering) can with the mm one while relocating the dirty side to the vent next to the oil cap and the clean side will stay connected on the intake behind the TB with a check valve. Second, I'm going to use the scavenging effect from the supercharger filter and connect the valley vent to it. According to the can builder the valley needs the most help to evacuate compared to the valve covers.
The mm can has a valved breather allowing any extra pressure to evacuate as needed but keeping the vent system relatively sealed. I'm keeping installed the breather/oil cap included in the ecs kit.
Last edited by Pitufina; Dec 14, 2014 at 11:31 PM.
Two -10 or 1/2" bungs/fittings on the valve covers, to a vented can.
I had issues all weekend blowing oil all over out of the breather cap like you pictured. Right now I have both covers vented to catch can, but the factory lines aren't big enough. I would take the valve covers off and put bigger fittings on, and just be done with it.
Two -10 or 1/2" bungs/fittings on the valve covers, to a vented can.
I had issues all weekend blowing oil all over out of the breather cap like you pictured. Right now I have both covers vented to catch can, but the factory lines aren't big enough. I would take the valve covers off and put bigger fittings on, and just be done with it.
I agree with Unreal. I just put -10 fitting in my valve covers and am waiting on MM catch cans.
Speak to Dave (Mightymouse) if you are not sure. He will guide you through the hookup for best results.
Two -10 or 1/2" bungs/fittings on the valve covers, to a vented can.
I had issues all weekend blowing oil all over out of the breather cap like you pictured. Right now I have both covers vented to catch can, but the factory lines aren't big enough. I would take the valve covers off and put bigger fittings on, and just be done with it.
Originally Posted by realcanuk
I agree with Unreal. I just put -10 fitting in my valve covers and am waiting on MM catch cans.
Speak to Dave (Mightymouse) if you are not sure. He will guide you through the hookup for best results.
I realized that bigger lines are preferred but it'll have to wait. Dave actually recommends the way I'll end up using.
I see where than can work on an n/a engine but I don't see where this can help when the engine is pressurized and needs help to evacuate that extra pressure.
Have over 20K miles on my S/C set up, and this has worked without issue. Both heads and the valley pan are allowed to vent the pressures to atmosphere, can't get much more vented than that. Other than actually hooking up a vacuum pump I'm not aware of a better way to do it.
Last edited by NormWild; Dec 15, 2014 at 02:03 PM.
I ran an Elite with no venting to the atmosphere for the last 3 years. Never had any issues whatsoever. Now that I am going to be running more boost I wanted a better setup, so I am going the the MM cans. I will hook them as Dave suggests.
There are obviously more than one way to make this work.
For me the key was a good vacuum into the can under boost and a good oil cap breather. Considering running a vented can just for ***** and grins since I'm upping the boost.
Have over 20K miles on my S/C set up, and this has worked without issue. Both heads and the valley pan are allowed to vent the pressures to atmosphere, can't get much more vented than that. Other than actually hooking up a vacuum pump I'm not aware of a better way to do it.
I was under the impression that FI engines need somewhat of a scavenging effect to help with extra internal pressure. I see what you're saying and it does makes sense too. Who knows lol
I ran an Elite with no venting to the atmosphere for the last 3 years. Never had any issues whatsoever. Now that I am going to be running more boost I wanted a better setup, so I am going the the MM cans. I will hook them as Dave suggests.
There are obviously more than one way to make this work.
Basically by the time I'm done I'll have two breathers. One(valve cover) will perform freely and the other(MM catch can) will vent when extra pressure is within the engine. The MM can has a valve in the breather that only allows venting and not vacuum, for those that don't know. Also the valley's pressure should be sucked by the sc filter.
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
Originally Posted by Unreal
Two -10 or 1/2" bungs/fittings on the valve covers, to a vented can.
this is what I did, -10an bungs on each valve cover to a breather can and cap off the valley and all vacuum ports on the intake/tb and eliminate the vacuum line going to the air filter... no chance of oil entering through the blower inlet/intake and it allows the motor to breathe
I decided to install a small breather on the driver's side valve cover using a check valve. I set it up that pressure will vent but no vacuum will come in. Did not want any unmetered air since it was tuned maf. Somehow I was not expecting the noticeable change in engine behavior and response. Could be on my head but nothing like this ever crossed my mind. Is that even possible? Engine seems to run smoother and much more pleasant to drive at low speeds, cruising, parking lot, etc The slight cam bucking I have is almost un-noticeable. Could this be possible?
Plumb the outlet of your valley cover through this and discharge it to the inlet of your compressor/supercharger. It will always pull down crankcase pressures, even during extended periods of boosting, and the cyclonic separator works better than most generic cans.
Dropped mine off to get welded up yesterday. What I landed up doing.
1/2" nipples welded to holley covers, 2 on each side. Then 2 1/2" lines from each valve cover to vented can.
Then 2nd sealed can from valley cover to inlet of blower. Depending on mounting we may do 2 cans for the vented 2 if there is a nice spot to mount.
Not too far off from what I am doing. Cans supposed to arrive today so I can get started on that soon. I didn't want to weld on the new Holley covers so I drilled and tapped for -10 AN fittings.
Plumb the outlet of your valley cover through this and discharge it to the inlet of your compressor/supercharger. It will always pull down crankcase pressures, even during extended periods of boosting, and the cyclonic separator works better than most generic cans.
I really like how factory that catch can looks. I wish I would have seen that one before I ordered the mighty mouse one. Btw, I'm surprised to see Greg posting. Thanks.
I didn't want to mess with expensive AN fittings, so weld on barbs are easy. Friends at AGP turbo are doing everything, and they make catchcans so they are just making me up some. Can't complain, just dropped off covers, and a few days later should all be done. They are also modifying my tensioner at the same time.
Boosted Engine Crankcase Pressure
