Passenger side valve cover port
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
NO! I DO NOT AGREE!
I have/had the same issue when I went with a FAST 90/90MM TB. The engine crank case ventilation is very important. The PCM is set up to account for an exact amount of crankcase ventilation (even in different engine load/throttle opening scenarios) If you cap it off:
1. You will not have an adequate supply of MAF metered fresh air to supply the block and PCV.
If you leave it open, you will be sucking is non filtered and non metered air.
Here is how I solved it on my engine. On the drivers side of the air bridge is a FLAT Spot. I drilled a hole into it and threaded in a BRASS fitting with a barbed nipple that would fit the vacuum line that comes off that PCV Vent nipple. I ran the hose under the TB and to that new brass nipple. Now I have a proper supply of fresh, filtered & properly metered air for the PCV System.
I have/had the same issue when I went with a FAST 90/90MM TB. The engine crank case ventilation is very important. The PCM is set up to account for an exact amount of crankcase ventilation (even in different engine load/throttle opening scenarios) If you cap it off:
1. You will not have an adequate supply of MAF metered fresh air to supply the block and PCV.
If you leave it open, you will be sucking is non filtered and non metered air.
Here is how I solved it on my engine. On the drivers side of the air bridge is a FLAT Spot. I drilled a hole into it and threaded in a BRASS fitting with a barbed nipple that would fit the vacuum line that comes off that PCV Vent nipple. I ran the hose under the TB and to that new brass nipple. Now I have a proper supply of fresh, filtered & properly metered air for the PCV System.
Last edited by Bill Curlee; Jun 2, 2017 at 12:35 PM.
Burning Brakes
Joined: Nov 2011
Posts: 1,037
Likes: 120
NO! I DO NOT AGREE!
Here is how I solved it on my engine. On the drivers side of the air bridge is a FLAT Spot. I drilled a hole into it and threaded in a BRASS fitting with a barbed nipple that would fit the vacuum line that comes off that PCV Vent nipple. I ran the hose under the TB and to that new brass nipple. Now I have a proper supply of fresh, filtered & properly metered air for the PCV System.
Here is how I solved it on my engine. On the drivers side of the air bridge is a FLAT Spot. I drilled a hole into it and threaded in a BRASS fitting with a barbed nipple that would fit the vacuum line that comes off that PCV Vent nipple. I ran the hose under the TB and to that new brass nipple. Now I have a proper supply of fresh, filtered & properly metered air for the PCV System.
thanks
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
When I first did my heads/cam/fast90 install, I was under a time crunch to get the car on the road to take it to Bowling Green. I,, like you, had the exact same dilemma.
Not wanting to cap it and wanting to make it properly functional as quick as possible, I punched a small hole into the rubber coupler between the bridge and TB, threaded in a small shallow brass fitting into the rubber coupler and hooked the hose up temporarily there.
To make it a more permanent install, I moved it to the other side of the air bridge. I don't have any pictures of that install as of this writing.
Not wanting to cap it and wanting to make it properly functional as quick as possible, I punched a small hole into the rubber coupler between the bridge and TB, threaded in a small shallow brass fitting into the rubber coupler and hooked the hose up temporarily there.
To make it a more permanent install, I moved it to the other side of the air bridge. I don't have any pictures of that install as of this writing.
Last edited by Bill Curlee; Jun 2, 2017 at 01:00 PM.
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Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
YES! Between the MAF and TB.
Look on the drivers side of the OEM plastic Air Bridge. You will see a round FLAT SPOT on the SIDE of the plastic air bridge. Go to AutoZone or even Home Depot, look in the brass fitting section for a 90 deg fitting that has a threaded end and a barbed hose nipple.
Find a drill bit that is a little smaller than the threaded end and drill a hole into the air bridge. Use a little firm pressure and crank the fitting into the hole. It will thread in like it was a factory part!
Simple and easy!
Last edited by Bill Curlee; Jun 2, 2017 at 01:29 PM.
Burning Brakes
Joined: Jan 2007
Posts: 968
Likes: 122
From: Lighthouse Point FL
Best is to swap in an LS6 valley pan. That's what I did. I run the PVC in the valley pan to a catch can and from there to the port on the throttle body. Simplifies PVC plumbing.
FWIW Z06 and later Vettes do not use these valve covers. They moved the PVC to the valley pan.
FWIW Z06 and later Vettes do not use these valve covers. They moved the PVC to the valley pan.
Last edited by maj75; Jun 4, 2017 at 08:11 PM.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
WHY,,, YES IT IS! A good forum member asked me to take a picture of something in the middle of a SNOW STORM, so,,, I got my boots on and went out and took the pictures! 
That vent was a quick work around to get the car on a road after the head cam fast 90 install. I have since made it a permanent install with that 90 deg brass fitting on the side of the air bridge.
Bill
That vent was a quick work around to get the car on a road after the head cam fast 90 install. I have since made it a permanent install with that 90 deg brass fitting on the side of the air bridge.
Bill
Supporting Vendor
Joined: Aug 2013
Posts: 1,375
Likes: 303
From: Virginia
when you switch away from a throttle body with a port at the top of it, you just need to connect out in front of it somewhere.
it is not intuitive but the port on top of the throttle body routes internally to in front of the blade, so all you have to do is mimic that.
this is where the pcv gets its fresh air supply from, so it is important that it is firstly measured by the MAF sensor before use to keep the computer happy.
there are a few photos mixed in at the bottom of my customer gallery link here of how some customers have done it.
https://drive.google.com/drive/folde...V9LN2M1Q0IyUGs
the ls6+ ported valley cover is a fine replacement for the older 'floating' pcv valve assembly. make sure you get the cover with the pcv built into it, as one of the original version still required an external valve.
while the ported valley is a more modern feature i like it only because of the built in pcv and not for measurably better oil control in my experience. either application for best consumption control a catch can is the right choice.
alternately with my max effort system (PCV can on my site), the pcv control is built into the can, so any other pcv valve or orifice on the car can be eliminated all together for better crankcase pressure (and clean side oil) control.
it is not intuitive but the port on top of the throttle body routes internally to in front of the blade, so all you have to do is mimic that.
this is where the pcv gets its fresh air supply from, so it is important that it is firstly measured by the MAF sensor before use to keep the computer happy.
there are a few photos mixed in at the bottom of my customer gallery link here of how some customers have done it.
https://drive.google.com/drive/folde...V9LN2M1Q0IyUGs
the ls6+ ported valley cover is a fine replacement for the older 'floating' pcv valve assembly. make sure you get the cover with the pcv built into it, as one of the original version still required an external valve.
while the ported valley is a more modern feature i like it only because of the built in pcv and not for measurably better oil control in my experience. either application for best consumption control a catch can is the right choice.
alternately with my max effort system (PCV can on my site), the pcv control is built into the can, so any other pcv valve or orifice on the car can be eliminated all together for better crankcase pressure (and clean side oil) control.
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Solutions for the common gearhead #made in USA
mightymousesolutions.com
facebok.com/mightymousesolutions
#mmsolutions
Six time NMCA True Street Champions
Home of the first Twin Turbo C7Z 7.81 @ 176
3470# Stock bottom end and heads Corvette Stock Bottom End Record Holder
Last edited by David@MMS; Jun 8, 2017 at 01:12 PM.
