My current PCV
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,931
Likes: 2
From: Tx
My current PCV
There has been a lot of talk about PCV setups again recently and a few people have asked me to explain how mine is setup. I spent a lot of time and money playing around with different PCV setups on my car a few years back. Each setup had positives and negatives, but I finally ended up with something that seems to work fairly well.
I ran a completely vented system for quite a while, but got sick of the smell and I also realized that I could get a little more low end responsiveness if I could get better ring seal in off boost conditions from vacuum on the crankcase.
So this is what I came up.
http://i21.photobucket.com/albums/b2...er2002/PCV.jpg
http://i21.photobucket.com/albums/b2...02/pcv_pic.jpg
I’ve been running this for about 6months now with no issues to speak of. This is basically two setups in one. A pretty normal PCV in off boost conditions and then a vented setup once the boost hits. I have no PCV valve in this setup. Instead, I use the adjustable restrictor valve to dial in the vacuum that I want to run against the crankcase at idle (think I have it set around 10inHG). I wanted to eventually do a vacuum regulator and only vent when I lost all crankcase vacuum, but I had trouble finding the parts at a reasonable price.
A few basic notes about the steup: Catch can1 is an AMW with the filter media… Catch can2 is just a basic Greddy can. The air filter on the fresh air side is a tiny little breather. My valve covers already had the nipples… since I originally did not have the valley cover with the vent (I added that later).
Some may wonder why the valves and restrictor are required. This is basically to allow a true vacuum on the crankcase. Without them all the air would just move through the crankcase as a vacuum leak.
I ran a completely vented system for quite a while, but got sick of the smell and I also realized that I could get a little more low end responsiveness if I could get better ring seal in off boost conditions from vacuum on the crankcase.
So this is what I came up.
http://i21.photobucket.com/albums/b2...er2002/PCV.jpg
http://i21.photobucket.com/albums/b2...02/pcv_pic.jpg
I’ve been running this for about 6months now with no issues to speak of. This is basically two setups in one. A pretty normal PCV in off boost conditions and then a vented setup once the boost hits. I have no PCV valve in this setup. Instead, I use the adjustable restrictor valve to dial in the vacuum that I want to run against the crankcase at idle (think I have it set around 10inHG). I wanted to eventually do a vacuum regulator and only vent when I lost all crankcase vacuum, but I had trouble finding the parts at a reasonable price.
A few basic notes about the steup: Catch can1 is an AMW with the filter media… Catch can2 is just a basic Greddy can. The air filter on the fresh air side is a tiny little breather. My valve covers already had the nipples… since I originally did not have the valley cover with the vent (I added that later).
Some may wonder why the valves and restrictor are required. This is basically to allow a true vacuum on the crankcase. Without them all the air would just move through the crankcase as a vacuum leak.
Last edited by QuickSilver2002; Sep 5, 2005 at 02:37 PM.
Safety Car
Joined: Nov 2003
Posts: 4,550
Likes: 3
From: Houston Texas
pcv
Originally Posted by QuickSilver2002
There has been a lot of talk about PCV setups again recently and a few people have asked me to explain how mine is setup. I spent a lot of time and money playing around with different PCV setups on my car a few years back. Each setup had positives and negatives, but I finally ended up with something that seems to work fairly well.
I ran a completely vented system for quite a while, but got sick of the smell and I also realized that I could get a little more low end responsiveness if I could get better ring seal in off boost conditions from vacuum on the crankcase.
So this is what I came up.
http://i21.photobucket.com/albums/b2...er2002/PCV.jpg
http://i21.photobucket.com/albums/b2...02/pcv_pic.jpg
I’ve been running this for about 6months now with no issues to speak of. This is basically two setups in one. A pretty normal PCV in off boost conditions and then a vented setup once the boost hits. I have no PCV valve in this setup. Instead, I use the adjustable restrictor valve to dial in the vacuum that I want to run against the crankcase at idle (think I have it set around 10inHG). I wanted to eventually do a vacuum regulator and only vent when I lost all crankcase vacuum, but I had trouble finding the parts at a reasonable price.
A few basic notes about the steup: Catch can1 is an AMW with the filter media… Catch can2 is just a basic Greddy can. The air filter on the fresh air side is a tiny little breather. My valve covers already had the nipples… since I originally did not have the valley cover with the vent (I added that later).
Some may wonder why the valves and restrictor are required. This is basically to allow a true vacuum on the crankcase. Without them all the air would just move through the crankcase as a vacuum leak.
I ran a completely vented system for quite a while, but got sick of the smell and I also realized that I could get a little more low end responsiveness if I could get better ring seal in off boost conditions from vacuum on the crankcase.
So this is what I came up.
http://i21.photobucket.com/albums/b2...er2002/PCV.jpg
http://i21.photobucket.com/albums/b2...02/pcv_pic.jpg
I’ve been running this for about 6months now with no issues to speak of. This is basically two setups in one. A pretty normal PCV in off boost conditions and then a vented setup once the boost hits. I have no PCV valve in this setup. Instead, I use the adjustable restrictor valve to dial in the vacuum that I want to run against the crankcase at idle (think I have it set around 10inHG). I wanted to eventually do a vacuum regulator and only vent when I lost all crankcase vacuum, but I had trouble finding the parts at a reasonable price.
A few basic notes about the steup: Catch can1 is an AMW with the filter media… Catch can2 is just a basic Greddy can. The air filter on the fresh air side is a tiny little breather. My valve covers already had the nipples… since I originally did not have the valley cover with the vent (I added that later).
Some may wonder why the valves and restrictor are required. This is basically to allow a true vacuum on the crankcase. Without them all the air would just move through the crankcase as a vacuum leak.
Where did you get your parts
Thanks
Safety Car
Joined: Jul 2005
Posts: 4,275
Likes: 4
From: Vancouver WA
Has anyone tried using a Crankcase Evacuation System like from Moroso? These pull crankcase pressure out via exhaust. I would think this would be great for F/I.. Except I am not sure what effects it might have on the Cats if it pulls much oil thru the system.
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,931
Likes: 2
From: Tx
Originally Posted by kromberg
Interesting setup. Why not just vent to the air with a Metco Valvecover breather?
Keith
Keith
You don't really need a vacuum in boost because the cylinder pressure and heat will push the rings out. A slight vacuum under boost would be nice, but it is difficult to maintain without a pump.
This is not just some hair brained scheme without putting any thought or testing into it. I’ve had no less than 15 different PCV setups on my car. It still has room for improvement (with some of the parts I mentioned in the original post), but it is the best setup I have had so far (for a street car).
Where can I get that adjustable restrictor valve?
If you do not have the valley cover with the vent could you run the blue line from the catch can to the vavle cover where you show an air filter? If yes would you need the adj restrictor?
Where did you get your parts
Thanks
Where did you get your parts
Thanks
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Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,931
Likes: 2
From: Tx
Originally Posted by RED99
Has anyone tried using a Crankcase Evacuation System like from Moroso? These pull crankcase pressure out via exhaust. I would think this would be great for F/I.. Except I am not sure what effects it might have on the Cats if it pulls much oil thru the system.
It only works at WOT and high RPM and the air that it moves is pretty minimal. It also pushes a little exhaust back upstream in non WOT conditions (it has check valves but they let a little air move between pulses at low RPM). This is not an issue if you are just venting, but it is the reason I don't have it hooked up right now. I might try it again at some point, but my current thought is that it is not worth it.
I actually have the ability to data log crankcase pressure with my setup, so I plan to do several different experiments once I get some other tuning issues worked out (I’m in the process of switching to SD and removing the MAF right now).
Last edited by QuickSilver2002; Sep 6, 2005 at 11:35 AM.
Safety Car
Joined: Apr 2004
Posts: 3,932
Likes: 8
From: Hayward California
Thanks for posting the info Quick..
This is an area that is still deserving attention (at least on my car
) since I don't have a pcv system.. everything just breathes to open air. It's looks to be pretty well thought out and will most likely be how I go about doing things when the time comes.. 
What quantities of oil did you find in the two catch cans? The reason I ask is that I may run a single can if there isn't a significant difference..
This is an area that is still deserving attention (at least on my car
) since I don't have a pcv system.. everything just breathes to open air. It's looks to be pretty well thought out and will most likely be how I go about doing things when the time comes.. What quantities of oil did you find in the two catch cans? The reason I ask is that I may run a single can if there isn't a significant difference..
Former Vendor
Joined: Feb 2004
Posts: 10,876
Likes: 8
From: Las Vegas NV
St. Jude Donor '06 & '12
OK, I kind of re-did my PCV system based on your set up. If you look at the drawing you will see the system has a normally closed check valve on the air cleaner. This way when the car is under vacum the vacum drawn by the intake port is what evacuates the crank case and valve covers. When my car is under boost the the intake port closes and the vacum from the air filter draw takes over.
With this setup there will never be a time where the Crank case is in a pressurized state. Correct??
Since my PCV system is a balanced system (Valve Cover & PCV) there is no reason to seperate the 2. If it was the laster model LS6 system then I would have to re-configure it.
What do you think?
Comments??
Jeff
With this setup there will never be a time where the Crank case is in a pressurized state. Correct??
Since my PCV system is a balanced system (Valve Cover & PCV) there is no reason to seperate the 2. If it was the laster model LS6 system then I would have to re-configure it.
What do you think?
Comments??
Jeff
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,931
Likes: 2
From: Tx
That would basically work, but I see two problems.
1. You have no fresh air source at all. This will result in excessive vacuum on the crankcase and could potentially cause oiling problems. It also allows no circulation and therefore eliminates the goodness that the PCV normally provides for keeping the oil clean...
2. You are going to be blowing oily vapor into the air filter/intake under boost. This will cling to the fins in your intercooler and will eventually make its way to the motor and a visit from mr. detonation becomes more likely.
You also need an extra check valve to backup the PCV valve. Thos things usually can't hold boost.
It is fine to run just 1 catch can. You could also replace the solenoid in my setup with a 1 way check valve. The only issues with check valves on the vent side is that they require cracking pressure. I wanted to avoid that in my setup.
1. You have no fresh air source at all. This will result in excessive vacuum on the crankcase and could potentially cause oiling problems. It also allows no circulation and therefore eliminates the goodness that the PCV normally provides for keeping the oil clean...
2. You are going to be blowing oily vapor into the air filter/intake under boost. This will cling to the fins in your intercooler and will eventually make its way to the motor and a visit from mr. detonation becomes more likely.
You also need an extra check valve to backup the PCV valve. Thos things usually can't hold boost.
It is fine to run just 1 catch can. You could also replace the solenoid in my setup with a 1 way check valve. The only issues with check valves on the vent side is that they require cracking pressure. I wanted to avoid that in my setup.
Last edited by QuickSilver2002; Sep 6, 2005 at 02:52 PM.
Former Vendor
Joined: Feb 2004
Posts: 10,876
Likes: 8
From: Las Vegas NV
St. Jude Donor '06 & '12
Originally Posted by QuickSilver2002
1. You have no fresh air source at all. This will result in excessive vacuum on the crankcase and could potentially cause oiling problems. It also allows no circulation and therefore eliminates the goodness that the PCV normally provides for keeping the oil clean...
2. You are going to be blowing oily vapor into the air filter/intake under boost. This will cling to the fins in your intercooler and will eventually make its way to the motor and a visit from mr. detonation becomes more likely.
You also need an extra check valve to backup the PCV valve. Thos things usually can't hold boost.
2)Actually the line coming from the air filter is "After" the catch can not before.
3) I actually do have a check valve. Its right in line with the PCV valve
Melting Slicks
Joined: Jan 2003
Posts: 3,251
Likes: 4
Quick,
Will that line with the solenoid flow enough to relieve blowby at 6000rpm? I can't imagine that a single 3/8" line will flow properly and worse if the solenoid sticks closed. What happens between 0 inHg and 3 psi? The system is actually closed up tight and I'm realtively certain that you will have some blowby then as well. Rather than the solenoid maybe rethink it using a "Krank Vent." no crack pressure but seals under vacuum and flows well, also possibly increase the line size.
I like the restrictor, I'm going to play with that idea. Does it resist chemicals and heat? otherwise it's useless.EDIT: Does it flow both ways?As far as the Greddy, I'd remove it. Just run it to atmosphere below the car. It's only active under boost anyway, I have the electric pump dumping below the car and there's never an oil drip or odor from it by the time I get home.
I'm not trying to be critical, I am as interested in a system that works as much as the next guy. 15 attempts? Thomas Edison tried 2000 times before he got the light bulb to work.
Last edited by IM QUIKR; Sep 7, 2005 at 08:00 AM.
Former Vendor
Joined: Feb 2004
Posts: 10,876
Likes: 8
From: Las Vegas NV
St. Jude Donor '06 & '12
This information is "directly" from my propriatary GM database. If anyone wonders how I got it. Welllll. Check my sig. My reason for posting is to inform everyone HOW/WHY we have a PCV system. I learned something today. Most of you already know this though
My reason for posting is to inform everyone HOW/WHY we have a PCV system. I learned something today. Most of you already know this though
Document ID# 752307
2002 Chevrolet Corvette
Crankcase Ventilation System Inspection/Description
A closed crankcase ventilation system is used in order to provide a more complete scavenging of crankcase vapors. Fresh air from the throttle body is supplied to the crankcase, mixed with the blow-by vapors and then passed through a crankcase ventilation valve and into the intake manifold. The primary component in the positive crankcase ventilation (PCV) system is the PCV valve, the valve meters the flow of blow-by vapors at a certain rate depending on manifold vacuum. To maintain idle quality, the PCV valve restricts the vapor flow when manifold vacuum is high. If abnormal operating conditions arise, the PCV system is designed to allow excessive amounts of blow-by vapors to back flow through the crankcase vent tube and into the engine air inlet to be consumed be normal combustion. The engine ventilation system was developed to minimize oil consumption and ensure that oil ingestion could not occur during vehicle limit handling maneuvers.
LS1 Engine
On the LS1 engine, filtered fresh air is routed from up stream of the throttle blade to the front of the right valve rocker arm cover through a formed rubber hose. To reduce the potential of oil pullover into the throttle bore area due to back flow of the ventilation system; the fitting in the right side rocker cover is shielded from the rocker arms and their oil spray. Blow-by vapors are routed from the rear of both rocker covers, through molded nylon lines to a tee fitting located on the centerline of the engine at the rear of the intake manifold. From there, a single nylon line carries the vapors through an externally mounted, horizontal PCV valve and enters the intake manifold behind the throttle body.
The dual draw PCV system was developed to meet the limited handling maneuver requirements. During sustained passively lateral accelerations, the outboard cover may fill with oil. The dual draw system passively switches, allowing the PCV valve to draw on the rocker cover with the least resistance. This results in the system drawing on the air filled, or inboard rocker cover and eliminates oil pullover due to drawing on the oil filled outboard rocker cover.
The PCV valve is connected to the PCV valve pipe. The PCV valve pipe is attached to the coolant air bleed pipe by a cable with an integral fastener. This cable transfers heat to the PCV valve to eliminate condensation build-up in the PCV system. This also aids in eliminating throttle body icing.
LS6 Engine
The LS6 engine utilizes an integral PCV system. The PCV system is moved into the engine's valley. The valley cover has composite oil separating baffles and PCV plumbing incorporated. The filtered fresh air is routed from up stream of the throttle blade to the front of the right valve rocker arm cover through a formed rubber hose. To reduce the potential of oil pullover into the throttle bore area due to back flow of the ventilation system; the fitting in the right side rocker cover is shielded from the rocker arms and their oil spray. Blow-by vapors are routed from the valley cover, through a formed rubber hose that carries the vapors through an externally mounted, horizontal PCV valve and enters the intake manifold behind the throttle body.
--------------------------------------------------------------------------------
Document ID# 752307
2002 Chevrolet Corvette
2002 Chevrolet Corvette
Crankcase Ventilation System Inspection/Description
A closed crankcase ventilation system is used in order to provide a more complete scavenging of crankcase vapors. Fresh air from the throttle body is supplied to the crankcase, mixed with the blow-by vapors and then passed through a crankcase ventilation valve and into the intake manifold. The primary component in the positive crankcase ventilation (PCV) system is the PCV valve, the valve meters the flow of blow-by vapors at a certain rate depending on manifold vacuum. To maintain idle quality, the PCV valve restricts the vapor flow when manifold vacuum is high. If abnormal operating conditions arise, the PCV system is designed to allow excessive amounts of blow-by vapors to back flow through the crankcase vent tube and into the engine air inlet to be consumed be normal combustion. The engine ventilation system was developed to minimize oil consumption and ensure that oil ingestion could not occur during vehicle limit handling maneuvers.
LS1 Engine
On the LS1 engine, filtered fresh air is routed from up stream of the throttle blade to the front of the right valve rocker arm cover through a formed rubber hose. To reduce the potential of oil pullover into the throttle bore area due to back flow of the ventilation system; the fitting in the right side rocker cover is shielded from the rocker arms and their oil spray. Blow-by vapors are routed from the rear of both rocker covers, through molded nylon lines to a tee fitting located on the centerline of the engine at the rear of the intake manifold. From there, a single nylon line carries the vapors through an externally mounted, horizontal PCV valve and enters the intake manifold behind the throttle body.
The dual draw PCV system was developed to meet the limited handling maneuver requirements. During sustained passively lateral accelerations, the outboard cover may fill with oil. The dual draw system passively switches, allowing the PCV valve to draw on the rocker cover with the least resistance. This results in the system drawing on the air filled, or inboard rocker cover and eliminates oil pullover due to drawing on the oil filled outboard rocker cover.
The PCV valve is connected to the PCV valve pipe. The PCV valve pipe is attached to the coolant air bleed pipe by a cable with an integral fastener. This cable transfers heat to the PCV valve to eliminate condensation build-up in the PCV system. This also aids in eliminating throttle body icing.
LS6 Engine
The LS6 engine utilizes an integral PCV system. The PCV system is moved into the engine's valley. The valley cover has composite oil separating baffles and PCV plumbing incorporated. The filtered fresh air is routed from up stream of the throttle blade to the front of the right valve rocker arm cover through a formed rubber hose. To reduce the potential of oil pullover into the throttle bore area due to back flow of the ventilation system; the fitting in the right side rocker cover is shielded from the rocker arms and their oil spray. Blow-by vapors are routed from the valley cover, through a formed rubber hose that carries the vapors through an externally mounted, horizontal PCV valve and enters the intake manifold behind the throttle body.
--------------------------------------------------------------------------------
Document ID# 752307
2002 Chevrolet Corvette
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,931
Likes: 2
From: Tx
Originally Posted by IM QUIKR
Quick,
Will that line with the solenoid flow enough to relieve blowby at 6000rpm? I can't imagine that a single 3/8" line will flow properly and worse if the solenoid sticks closed. What happens between 0 inHg and 3 psi? The system is actually closed up tight and I'm realtively certain that you will have some blowby then as well. Rather than the solenoid maybe rethink it using a "Krank Vent." no crack pressure but seals under vacuum and flows well, also possibly increase the line size.
I like the restrictor, I'm going to play with that idea. Does it resist chemicals and heat? otherwise it's useless.[B
Quick,
Will that line with the solenoid flow enough to relieve blowby at 6000rpm? I can't imagine that a single 3/8" line will flow properly and worse if the solenoid sticks closed. What happens between 0 inHg and 3 psi? The system is actually closed up tight and I'm realtively certain that you will have some blowby then as well. Rather than the solenoid maybe rethink it using a "Krank Vent." no crack pressure but seals under vacuum and flows well, also possibly increase the line size.
I like the restrictor, I'm going to play with that idea. Does it resist chemicals and heat? otherwise it's useless.[B
EDIT: Does it flow both ways?[/B]As far as the Greddy, I'd remove it. Just run it to atmosphere below the car. It's only active under boost anyway, I have the electric pump dumping below the car and there's never an oil drip or odor from it by the time I get home.
I'm not trying to be critical, I am as interested in a system that works as much as the next guy. 15 attempts? Thomas Edison tried 2000 times before he got the light bulb to work.
I'm not trying to be critical, I am as interested in a system that works as much as the next guy. 15 attempts? Thomas Edison tried 2000 times before he got the light bulb to work.
Let me answer most of your questions with how I got here. My original plan for this rev was to run a vacuum regulator where the restrictor is. This would allow for the storage of vacuum in the catch can... In other words, the larger the catch can(s), the more time a vacuum would be held on the crankcase, when the original vacuum source was lost (follow?). I was also going to open the valve on the vent side as soon as all vacuum was lost.
I had trouble finding a vacuum regulator..., so I just threw together some parts I had lying around to see what would happen. I data logged crankcase pressure and drove the car under all types of conditions. It turned out that it worked fine. I never saw any pressure in the crankcase. I was concerned that it would have a transition problem, but it did not.
I guess there is a potential issue if you somehow held it just below 3psi for and extended period. An extra on way check valve would be a nice addition (like the krank vent), but I have an issue spending $100 on a valve.
Melting Slicks
Joined: Apr 2005
Posts: 3,418
Likes: 1
From: Chicagoland Area IL
Quick,
You have obviously put considerable thought into various revisions of your design.
Dumb question if you could always pull a bit of a vacuum, more at higher RPM, what would you do? With supercharged applications the potential to have beneficial pressure differential is there. As an example Procharger inlet face (impeller) has a low pressure region and with perpendicular flow an ejector flow stream can be created (yes a poor one with low efficiency). I know that if you can pull a vacuum on engine, HP will go up do to lower windage losses and other variables. The vacuum level has limits but if over 20 in. no problems should be seen with seals, oil starvation…
Mike
You have obviously put considerable thought into various revisions of your design.
Dumb question if you could always pull a bit of a vacuum, more at higher RPM, what would you do? With supercharged applications the potential to have beneficial pressure differential is there. As an example Procharger inlet face (impeller) has a low pressure region and with perpendicular flow an ejector flow stream can be created (yes a poor one with low efficiency). I know that if you can pull a vacuum on engine, HP will go up do to lower windage losses and other variables. The vacuum level has limits but if over 20 in. no problems should be seen with seals, oil starvation…
Mike
Last edited by Skunkworks; Sep 7, 2005 at 03:46 AM.
Melting Slicks
Joined: Jan 2003
Posts: 3,251
Likes: 4
Originally Posted by QuickSilver2002
Please don't post the image inline. I put it as a link for a reason (bandwidth limit). It won't last as long this way. .
.
Let me answer most of your questions with how I got here. My original plan for this rev was to run a vacuum regulator where the restrictor is. This would allow for the storage of vacuum in the catch can... In other words, the larger the catch can(s), the more time a vacuum would be held on the crankcase, when the original vacuum source was lost (follow?). I was also going to open the valve on the vent side as soon as all vacuum was lost..
.
I had trouble finding a vacuum regulator..., so I just threw together some parts I had lying around to see what would happen. I data logged crankcase pressure and drove the car under all types of conditions. It turned out that it worked fine. I never saw any pressure in the crankcase. I was concerned that it would have a transition problem, but it did not. .
.
I guess there is a potential issue if you somehow held it just below 3psi for and extended period. An extra on way check valve would be a nice addition (like the krank vent), but I have an issue spending $100 on a valve.
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,931
Likes: 2
From: Tx
Originally Posted by Skunkworks
Quick,
You have obviously put considerable thought into various revisions of your design.
Dumb question if you could always pull a bit of a vacuum, more at higher RPM, what would you do? With supercharged applications the potential to have beneficial pressure differential is there. As an example Procharger inlet face (impeller) has a low pressure region and with perpendicular flow an ejector flow stream can be created (yes a poor one with low efficiency). I know that if you can pull a vacuum on engine, HP will go up do to lower windage losses and other variables. The vacuum level has limits but if over 20 in. no problems should be seen with seals, oil starvation…
Mike
You have obviously put considerable thought into various revisions of your design.
Dumb question if you could always pull a bit of a vacuum, more at higher RPM, what would you do? With supercharged applications the potential to have beneficial pressure differential is there. As an example Procharger inlet face (impeller) has a low pressure region and with perpendicular flow an ejector flow stream can be created (yes a poor one with low efficiency). I know that if you can pull a vacuum on engine, HP will go up do to lower windage losses and other variables. The vacuum level has limits but if over 20 in. no problems should be seen with seals, oil starvation…
Mike
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,931
Likes: 2
From: Tx
Originally Posted by IM QUIKR
Alright, it's on my dime now.
.
I doubt you can retain any vacuum in the can for more than a fraction of a second just based on the air volume in the engine compared to that little can. it seems to be an academic exercise. KV would do just that without trying to time the event but I understand the $$.
.
It would interesting to measure the vacuum in the cc to see what actually exists
.
That's why I asked because I often drive just inside of boost. I'd hate to stress any seals that way.
.
I doubt you can retain any vacuum in the can for more than a fraction of a second just based on the air volume in the engine compared to that little can. it seems to be an academic exercise. KV would do just that without trying to time the event but I understand the $$.
.
It would interesting to measure the vacuum in the cc to see what actually exists
.
That's why I asked because I often drive just inside of boost. I'd hate to stress any seals that way.