VC Breather or Not?
06-24-2013, 07:16 AM
#1
VC Breather or Not? I just finished installing my LT4 Composite VCs and love them. The seller provided me with a very nice looking and functional breather for the oil filler hole on the passenger side. I have the fresh air hose already hooked up to the TB, so should I remove the breather and seal it up with a oil filler cap? I know there has been tons of talk on here about weather it can actually be source of unmetered air, but just not sure if it really matters? Let me know what you think and what you're running?
06-24-2013, 06:11 PM
#2
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From my understanding of the system, the air goes through that VC from the throttle body because the PCV system is pulling air out and bringing it in to the intake. Right? I feel like that having that system work as designed would be optimal along with getting rid of the minor oil consumption problem. At least for a majority of the N/A motors out there..
I did a few things that were recommended by people to keep it functional but remove the oil consumption aspect of it. I put a husky catch can from home depot on the PCV side of things (you can get basically the same thing at oreillys too) and a Purolator breather filter (P# B23165 ) on the TB to VC side of things (autozone has the Purolators). Works awesome.
When I got my LT4 covers I was unsure if the filter would fit being that it is on the side of the VC unlike the other covers, but it tucked in very nicely.
I attached a pic of what the pass. side looks like with the breather filter.
Drivers side just shows the hose routing from the intake, they end under the cowl right up against the firewall where I have the catch can mounted. It's just to the left of the brake vacuum cyl.
I did a few things that were recommended by people to keep it functional but remove the oil consumption aspect of it. I put a husky catch can from home depot on the PCV side of things (you can get basically the same thing at oreillys too) and a Purolator breather filter (P# B23165 ) on the TB to VC side of things (autozone has the Purolators). Works awesome.
When I got my LT4 covers I was unsure if the filter would fit being that it is on the side of the VC unlike the other covers, but it tucked in very nicely.
I attached a pic of what the pass. side looks like with the breather filter.
Drivers side just shows the hose routing from the intake, they end under the cowl right up against the firewall where I have the catch can mounted. It's just to the left of the brake vacuum cyl.
06-25-2013, 06:47 AM
#3
From my understanding of the system, the air goes through that VC from the throttle body because the PCV system is pulling air out and bringing it in to the intake. Right? I feel like that having that system work as designed would be optimal along with getting rid of the minor oil consumption problem. At least for a majority of the N/A motors out there..
I did a few things that were recommended by people to keep it functional but remove the oil consumption aspect of it. I put a husky catch can from home depot on the PCV side of things (you can get basically the same thing at oreillys too) and a Purolator breather filter (P# B23165 ) on the TB to VC side of things (autozone has the Purolators). Works awesome.
When I got my LT4 covers I was unsure if the filter would fit being that it is on the side of the VC unlike the other covers, but it tucked in very nicely.
I attached a pic of what the pass. side looks like with the breather filter.
Drivers side just shows the hose routing from the intake, they end under the cowl right up against the firewall where I have the catch can mounted. It's just to the left of the brake vacuum cyl.
I did a few things that were recommended by people to keep it functional but remove the oil consumption aspect of it. I put a husky catch can from home depot on the PCV side of things (you can get basically the same thing at oreillys too) and a Purolator breather filter (P# B23165 ) on the TB to VC side of things (autozone has the Purolators). Works awesome.
When I got my LT4 covers I was unsure if the filter would fit being that it is on the side of the VC unlike the other covers, but it tucked in very nicely.
I attached a pic of what the pass. side looks like with the breather filter.
Drivers side just shows the hose routing from the intake, they end under the cowl right up against the firewall where I have the catch can mounted. It's just to the left of the brake vacuum cyl.
Here's a pic of my setup:
06-25-2013, 07:50 AM
#4
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The unmetered air brought into the engine is not enough to cause any significant change. Just another source of argument just like the difference between a 5.8 and 6" connecting rod. You'll get opinions all over the map. IMO it's not necessary as long as your PCV system is still in tact.
06-25-2013, 08:33 AM
#5
The unmetered air brought into the engine is not enough to cause any significant change. Just another source of argument just like the difference between a 5.8 and 6" connecting rod. You'll get opinions all over the map. IMO it's not necessary as long as your PCV system is still in tact.
