ViperTony
10-26-2013, 02:31 PM
Preface
When I removed my intake for powder-coating I found oil residue in most of my intake runners. In fact, some runners were so filthy that the parts washers was blackened by it all! Apparently, oil residue/vapors was making it's way into my intake and ultimately into the cylinders impacting the octane rating. In tracing the source of this "contamination" I checked both the CCV (Crank Case Ventilation) and valve cover ventilation ports. Interestingly enough, my valve cover ports were producing almost no blow-by vapors while my CCV was producing much more. Upon closer inspection, I found that there was significant gunk around the CCV orifice on top of my block and very little, if not dry, residue in the lines exiting my valve covers to the air box.
For reference, this is the CCV orifice on a GenII ('02). The service manual describes it as a CCV that acts like a PCV valve:
http://driveviper.com/forums/attachment.php?attachmentid=242&d=1382815265
http://driveviper.com/forums/attachment.php?attachmentid=235&d=1382814720
This is actually nothing more than a rubber grommet made to fit the block with a barbed plastic fitting used to tie into a rubber hose that tees into the intake manifold. Excess crankcase pressure/blow-by makes it's way directly into the intake. I decided to vent the CCV but wanted to do so while maintaining vacuum. I didn't want to simply vent to a breather and lose any vacuum from the intake that may be helping draw out excess crankcase pressure. I basically wanted an air-oil separator.
After some searching, I found a separator I like. (It's actually for a Corvette ):
Oil Seperator: http://www.customcorvetteaccessories.com/oilcatchcan.html
Mounting Bracket: http://www.siliconeintakes.com/index.php
http://driveviper.com/forums/attachment.php?attachmentid=245&d=1382815413
It's actually a two-piece, chambered design:
http://driveviper.com/forums/attachment.php?attachmentid=240&d=1382815264
The basic principle behind this specific version is that oil gunk is separated (mostly) from the vapors/blow-by coming from the CCV valve allowing mostly clean air to make it's way to the intake.
This system comes with a bracket (which is useless) and 3/8" ID hose which is long enough to do the job on a Viper.
The catch-can has two hose connections: One connection (top) for incoming (blow-by) and a second connection for outgoing (mostly clean) back to the intake manifold. An overview of this is all hooked up:
http://driveviper.com/forums/attachment.php?attachmentid=246&d=1382815502
I disconnected the CCV hose that goes into the Tee (connecting to both intake tracts). I installed an elbow on this hose and connected the outgoing 3/8" ID hose to the catch can.
The return hose from the catch can gets hooked up to the Tee.
As for the catch can (oil separator), I decided to mount it to the front cross brace on the passenger side of the engine:
http://driveviper.com/forums/attachment.php?attachmentid=247&d=1382815563
The bracket that comes with the catch can is useless. Instead, I used a 2.5" t-bolt bracket:
http://driveviper.com/forums/attachment.php?attachmentid=248&d=1382815632
I drilled and installed two rivet nuts into the cross brace to attach the bracket. Overall cost was $117. With the hood removed (I had it removed for my head work) the mod took less than 20 minutes to complete.
CCV Hose Reference Pic
http://driveviper.com/forums/attachment.php?attachmentid=241&d=1382815265
Option #2:
There's another option to an air-oil separator and that's to simply cap the CCV valve and cap the ports on the intake where the CCV tees in. Easy to, easier with the intake removed.
http://driveviper.com/forums/attachment.php?attachmentid=236&d=1382814938
- ViperTony
When I removed my intake for powder-coating I found oil residue in most of my intake runners. In fact, some runners were so filthy that the parts washers was blackened by it all! Apparently, oil residue/vapors was making it's way into my intake and ultimately into the cylinders impacting the octane rating. In tracing the source of this "contamination" I checked both the CCV (Crank Case Ventilation) and valve cover ventilation ports. Interestingly enough, my valve cover ports were producing almost no blow-by vapors while my CCV was producing much more. Upon closer inspection, I found that there was significant gunk around the CCV orifice on top of my block and very little, if not dry, residue in the lines exiting my valve covers to the air box.
For reference, this is the CCV orifice on a GenII ('02). The service manual describes it as a CCV that acts like a PCV valve:
http://driveviper.com/forums/attachment.php?attachmentid=242&d=1382815265
http://driveviper.com/forums/attachment.php?attachmentid=235&d=1382814720
This is actually nothing more than a rubber grommet made to fit the block with a barbed plastic fitting used to tie into a rubber hose that tees into the intake manifold. Excess crankcase pressure/blow-by makes it's way directly into the intake. I decided to vent the CCV but wanted to do so while maintaining vacuum. I didn't want to simply vent to a breather and lose any vacuum from the intake that may be helping draw out excess crankcase pressure. I basically wanted an air-oil separator.
After some searching, I found a separator I like. (It's actually for a Corvette ):
Oil Seperator: http://www.customcorvetteaccessories.com/oilcatchcan.html
Mounting Bracket: http://www.siliconeintakes.com/index.php
http://driveviper.com/forums/attachment.php?attachmentid=245&d=1382815413
It's actually a two-piece, chambered design:
http://driveviper.com/forums/attachment.php?attachmentid=240&d=1382815264
The basic principle behind this specific version is that oil gunk is separated (mostly) from the vapors/blow-by coming from the CCV valve allowing mostly clean air to make it's way to the intake.
This system comes with a bracket (which is useless) and 3/8" ID hose which is long enough to do the job on a Viper.
The catch-can has two hose connections: One connection (top) for incoming (blow-by) and a second connection for outgoing (mostly clean) back to the intake manifold. An overview of this is all hooked up:
http://driveviper.com/forums/attachment.php?attachmentid=246&d=1382815502
I disconnected the CCV hose that goes into the Tee (connecting to both intake tracts). I installed an elbow on this hose and connected the outgoing 3/8" ID hose to the catch can.
The return hose from the catch can gets hooked up to the Tee.
As for the catch can (oil separator), I decided to mount it to the front cross brace on the passenger side of the engine:
http://driveviper.com/forums/attachment.php?attachmentid=247&d=1382815563
The bracket that comes with the catch can is useless. Instead, I used a 2.5" t-bolt bracket:
http://driveviper.com/forums/attachment.php?attachmentid=248&d=1382815632
I drilled and installed two rivet nuts into the cross brace to attach the bracket. Overall cost was $117. With the hood removed (I had it removed for my head work) the mod took less than 20 minutes to complete.
CCV Hose Reference Pic
http://driveviper.com/forums/attachment.php?attachmentid=241&d=1382815265
Option #2:
There's another option to an air-oil separator and that's to simply cap the CCV valve and cap the ports on the intake where the CCV tees in. Easy to, easier with the intake removed.
http://driveviper.com/forums/attachment.php?attachmentid=236&d=1382814938
- ViperTony