Nissan 370Z Forum  

PCV bypass

Hey all. Tired of having performance and mileage sapped away by the good 'ol epa? Tired of having an oily dirty intake? Try this mod and increase performance and mileage.

Go Back   Nissan 370Z Forum > Nissan 370Z Tech Area > Engine & Drivetrain


Like Tree5Likes

Reply
 
LinkBack Thread Tools Display Modes
Old 05-17-2014, 12:52 AM   #1 (permalink)
Track Member
 
Join Date: May 2014
Location: Riverside
Posts: 584
Drives: 40th 370Z
Rep Power: 11
lj909 is on a distinguished road
Default PCV bypass

Hey all. Tired of having performance and mileage sapped away by the good 'ol epa? Tired of having an oily dirty intake? Try this mod and increase performance and mileage. I have done this to both a HR350Z and now my 370Z and experienced over a mile per gallon increase. Performed wise is very little but if you're real in tune with your car you might notice it down low. The benefit comes from not sucking oil vapors and blow by vapors into your fresh combustion chamber and lowering your octane rating.
20140515_184602.jpg

2014-05-15_23.23.38.jpeg

2014-05-15_23.24.39.jpg

2014-05-15_23.26.35.jpg
__________________
PW 07 HR350Z R.I.P. Totaled by 82yr old woman
2010 40th Anniversary 370Z
lj909 is offline   Reply With Quote
Old 05-17-2014, 01:20 AM   #2 (permalink)
A True Z Fanatic
 
synolimit's Avatar
 
Join Date: May 2013
Location: Columbus, OH
Posts: 5,051
Drives: 2013 Silver 370z
Rep Power: 3388
synolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond repute
Default

Just a FYI this is illegal on a track since if the motor blows oil can come out the filters and onto the track. That's why people run a catch can or air oil separator still connected to the manifold since if the motor blows the oil is caught in the manifold and cylinders
__________________
13 370z-
synolimit is offline   Reply With Quote
Old 05-17-2014, 10:20 AM   #3 (permalink)
Track Member
 
Join Date: May 2014
Location: Riverside
Posts: 584
Drives: 40th 370Z
Rep Power: 11
lj909 is on a distinguished road
Default

Thanks for the info. I've never been to the track before. I have driven with this setup for a while though and never had a drop of leakage.
__________________
PW 07 HR350Z R.I.P. Totaled by 82yr old woman
2010 40th Anniversary 370Z
lj909 is offline   Reply With Quote
Old 05-17-2014, 10:24 AM   #4 (permalink)
Premium Member Bitches
 
DEpointfive0's Avatar
 
Join Date: Jan 2012
Location: SoCal
Posts: 14,824
Drives: a lot
Rep Power: 17151
DEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond reputeDEpointfive0 has a reputation beyond repute
Default

I ran with one of those, had a thin film of oil all over the engine bay... Wasn't worth it, but whatever works for you!
AstatenateZ likes this.
__________________
Do YOU want to know what/where I got my username from?
( Click to show/hide )
DEpointfive0 is offline   Reply With Quote
Old 05-17-2014, 04:20 PM   #5 (permalink)
A True Z Fanatic
 
synolimit's Avatar
 
Join Date: May 2013
Location: Columbus, OH
Posts: 5,051
Drives: 2013 Silver 370z
Rep Power: 3388
synolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond repute
Default

Quote:
Originally Posted by lj909 View Post
Thanks for the info. I've never been to the track before. I have driven with this setup for a while though and never had a drop of leakage.
I wouldn't expect it but I'd like to see a test of your HP theory. Reason why is you've removed a slight pull of suction of the bottom of the pistons since the intake lines been broken. On bikes its been shown to add HP since the suction aids in piston travel. With your connection being broken you've lost that action. I'd vote a loss of power, not a gain. Unless however you suck so much oil into the cylinders you were losing power. I still say best of both worlds is a AOS. No oil, no lost suction.
__________________
13 370z-
synolimit is offline   Reply With Quote
Old 05-17-2014, 06:45 PM   #6 (permalink)
Track Member
 
Join Date: May 2014
Location: Riverside
Posts: 584
Drives: 40th 370Z
Rep Power: 11
lj909 is on a distinguished road
Default

I'll be getting to the dyno one of these days. I'll try and remember to do a pull with and without. But the way these pcv valves work they close off at higher rpms anyways so it really only effects lower range. But from a chemistry standpoint, you get a better combustion a higher octane rating and less knock.
__________________
PW 07 HR350Z R.I.P. Totaled by 82yr old woman
2010 40th Anniversary 370Z
lj909 is offline   Reply With Quote
Old 05-23-2014, 06:35 AM   #7 (permalink)
Banned
 
Join Date: Jun 2010
Location: Ahnald, MO
Age: 46
Posts: 387
Drives: 09 K51 G C Bw/S 6MT
Rep Power: 0
L33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant future
Send a message via Yahoo to L33T Z34
Thumbs up

OP
I've got a similar set up. I didn't remove the PCV 2 Ntake many lines though.
I let 'em pull at low RPM, like u said, they close @ high RPM. I dump the valve cover breathers on teh gr0und. No oil residue in my engine bay.
L33T Z34 is offline   Reply With Quote
Old 05-23-2014, 12:09 PM   #8 (permalink)
Track Member
 
Join Date: May 2014
Location: Riverside
Posts: 584
Drives: 40th 370Z
Rep Power: 11
lj909 is on a distinguished road
Default

Oh that's a good idea to vent on the ground but if part of your system is still hooked up then your sucking unmeasured air and messing with your a/r ratio. Also if your still sucking from the pvc then your not getting the little benefit.
__________________
PW 07 HR350Z R.I.P. Totaled by 82yr old woman
2010 40th Anniversary 370Z
lj909 is offline   Reply With Quote
Old 05-23-2014, 07:33 PM   #9 (permalink)
A True Z Fanatic
 
synolimit's Avatar
 
Join Date: May 2013
Location: Columbus, OH
Posts: 5,051
Drives: 2013 Silver 370z
Rep Power: 3388
synolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond repute
Default

Quote:
Originally Posted by lj909 View Post
Oh that's a good idea to vent on the ground but if part of your system is still hooked up then your sucking unmeasured air and messing with your a/r ratio. Also if your still sucking from the pvc then your not getting the little benefit.
I know a subi is different but I used to vent to the ground also (very illegal for a track!!). Then I started getting faster in high G corners and was dumping all my oil out the valve cover breathers. My car was soaked in oil!!! That's why they have to run a catch and return system. But instead of hooking it up oem style to the mani where the motor will burn it up lowering HP, AFR, oil level, we hooked the return to the crank case breather so whatever got spit out went back in to a safer/better place. Not sure if its a Z problem but someone who can fuel starve in high G right handers would need to confirm yes or no.
__________________
13 370z-

Last edited by synolimit; 05-23-2014 at 07:36 PM.
synolimit is offline   Reply With Quote
Old 05-25-2014, 07:34 PM   #10 (permalink)
Banned
 
Join Date: Jun 2010
Location: Ahnald, MO
Age: 46
Posts: 387
Drives: 09 K51 G C Bw/S 6MT
Rep Power: 0
L33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant futureL33T Z34 has a brilliant future
Send a message via Yahoo to L33T Z34
Talking OEM service manual PCV diagram

Let me modify page EC-509 of the '09 service manual to show you how I do it. Where the red x's are I placed K&N crank case breathers on the valve covers. This dumps to the ground/atmosphere. Where the red x's are on the intake (accordion tubes) I placed pipe plugs to seal the holes, no vacuum leaks. I do not remove the PCV valves or the hoses off of these to the intake manny. I simply do not want blow by gasses being dumped into my intake before the TBs during "full throttle" conditions. As LJ stated, this keeps the intake air CLEAN and COOLER, thus subsiding detonation.
Attached Images
File Type: jpg PCV Diagram Anno.jpg (202.1 KB, 109 views)
L33T Z34 is offline   Reply With Quote
Old 05-25-2014, 09:46 PM   #11 (permalink)
A True Z Fanatic
 
synolimit's Avatar
 
Join Date: May 2013
Location: Columbus, OH
Posts: 5,051
Drives: 2013 Silver 370z
Rep Power: 3388
synolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond repute
Default

Quote:
Originally Posted by L33T Z34 View Post
Let me modify page EC-509 of the '09 service manual to show you how I do it. Where the red x's are I placed K&N crank case breathers on the valve covers. This dumps to the ground/atmosphere. Where the red x's are on the intake (accordion tubes) I placed pipe plugs to seal the holes, no vacuum leaks. I do not remove the PCV valves or the hoses off of these to the intake manny. I simply do not want blow by gasses being dumped into my intake before the TBs during "full throttle" conditions. As LJ stated, this keeps the intake air CLEAN and COOLER, thus subsiding detonation.
So I just took all my catch can and stuff apart (had a leak). I've noticed my hoses on the front of the mani coming from the catch can now have oil in them. But that's impossible because my catch can doesn't allow this! So I'm assuming the oil is not coming from the catch can/PCV valves, but from the inside of the manifold since my Z1 post tubes still are hooked up normal to the valve covers?

I'm not doing a dump to atmos when I have a proper CC! But I'm not sure I feel comfortable blocking off the post tube port and the valve cover head. Its gotta be there for a reason.
__________________
13 370z-
synolimit is offline   Reply With Quote
Old 05-26-2014, 02:00 AM   #12 (permalink)
Track Member
 
Join Date: May 2014
Location: Riverside
Posts: 584
Drives: 40th 370Z
Rep Power: 11
lj909 is on a distinguished road
Default

I'm not sure exactly how catch cans are made but from what I've seen they are made like a baffle? With no real filter in them. Am I right? If so, then they're not doing what they claim to do because the oil and blow by are in the form of vapors, which will stay in the air until they land on something. So no matter how many baffles there are, some vapors will always get through.
__________________
PW 07 HR350Z R.I.P. Totaled by 82yr old woman
2010 40th Anniversary 370Z
lj909 is offline   Reply With Quote
Old 05-26-2014, 04:06 AM   #13 (permalink)
A True Z Fanatic
 
synolimit's Avatar
 
Join Date: May 2013
Location: Columbus, OH
Posts: 5,051
Drives: 2013 Silver 370z
Rep Power: 3388
synolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond repute
Default

Quote:
Originally Posted by lj909 View Post
I'm not sure exactly how catch cans are made but from what I've seen they are made like a baffle? With no real filter in them. Am I right? If so, then they're not doing what they claim to do because the oil and blow by are in the form of vapors, which will stay in the air until they land on something. So no matter how many baffles there are, some vapors will always get through.
Technically a catch can is literally just a can. Once you add baffle you've made a air/oil separator or AOS. Some people throw steel wool into a catch can but a real AOS has a baffle system. Here's a pic of what I use below. The inlets are angled so the air hits the sides and has to swirl around the sides collecting. If some is still air borne it has to make its way into the second chamber collecting on its sides. Then suspended in mid air is the return tube. Its impossible for oil to make it through everything. My subi, ram 1500 and Z have all had bone dry returns till the Z now. Since again I think its coming from the manifold under WOT and not the AOS.
Attached Images
File Type: jpg image.jpg (204.4 KB, 80 views)
__________________
13 370z-

Last edited by synolimit; 05-26-2014 at 04:09 AM.
synolimit is offline   Reply With Quote
Old 05-27-2014, 11:01 PM   #14 (permalink)
Track Member
 
Join Date: May 2014
Location: Riverside
Posts: 584
Drives: 40th 370Z
Rep Power: 11
lj909 is on a distinguished road
Default

Thanks for the CC picture post. Could you possibly be getting reverse suction from the fresh air tube's? I couldn't think of any other way that oil could build up in the manifold.
__________________
PW 07 HR350Z R.I.P. Totaled by 82yr old woman
2010 40th Anniversary 370Z
lj909 is offline   Reply With Quote
Old 05-28-2014, 09:23 AM   #15 (permalink)
A True Z Fanatic
 
synolimit's Avatar
 
Join Date: May 2013
Location: Columbus, OH
Posts: 5,051
Drives: 2013 Silver 370z
Rep Power: 3388
synolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond reputesynolimit has a reputation beyond repute
Default

Idk, L33T thinks so it looks like.
__________________
13 370z-
synolimit is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Car kit company bypass kit RoadsterST Nissan 370Z General Discussions 0 11-27-2013 07:15 PM
Bypass valve Mrbiker Forced Induction 0 10-07-2011 06:12 PM
Video bypass....tr-7 HT Rambler Audio & Video 0 06-23-2010 09:51 PM
audio/video bypass Zyonara Audio & Video 1 12-28-2009 11:31 PM
how do you bypass the AVN726E ktzdaman Audio & Video 5 07-17-2009 05:46 PM


All times are GMT -5. The time now is 04:52 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2