Bypass valve or Blow off valve for Procharger?
10-26-2007, 08:48 PM
#1
Melting Slicks
Thread Starter
Bypass valve or Blow off valve for Procharger?
I found like so many other forum members that my stock Procharger bypass valve is leaking boost when closed. So I started looking and found that there are allot more members changing over to BOV on there supercharger systems rather than replacing there bypass valve. I know they work for Turbos but are they ok for supercharger systerms? Any advice would be great.
10-26-2007, 11:38 PM
#2
Team Owner
I found like so many other forum members that my stock Procharger bypass valve is leaking boost when closed. So I started looking and found that there are allot more members changing over to BOV on there supercharger systems rather than replacing there bypass valve. I know they work for Turbos but are they ok for supercharger systerms? Any advice would be great.
It should not be hard to fix the Bypass valve it's only a diaphram operated by Vacumm and B@@ST!
Do you have enough Vacumm to operate it at idle to keep it open and then under B@@ST to push it closed or have you checked it by taking it off the Vette and bench testing it?
Because if it is bad it will be bad at idle too or it should be if it is failing to hold Vacumm or B@@ST!
Call ProCharger and ask them what they think or if they have a remedy!
BOV are good but I haven't heard of one on a ProCharger but would be curious to see if any have used them and with any success!
Thanks,Matt
10-27-2007, 12:43 AM
#3
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Not sure how relevant because I am unfamilar with the Procharger. The tech support guy from Vortech told me that if the car has a MAF that you have to use a bypass. If it doesn't you can use either bypass or BOV.
10-27-2007, 07:52 AM
#5
The ProCharger Proflow bypass valve is always going to have a slight leakage. We don't normally see the leakage to be significant enough to alter the amount of boost the blower produces. We've only had one faulty valve that I can remember. We replaced it and picked up two pounds of boost on a V6 Mustang kit.
A Bypass valve is always going to be discharging the boost until the engine goes to near zero vacuum, and the valve closes. This is critical because a supercharger is belt driven and is always producing boost. When you are driving, say in traffic and you let off the gas, that boost will get stacked up if you don't have a bypass valve. That stacked up boost will have no where to go but push back against the blower or find a weak spot in the plumbing.
A blow off valve blows off the boost at a set psi. A blow off valve works great for a turbo system, which typically doesn't produce any measurable boost until the engine is loaded and producing some exhaust velocity. You don't want to use a blow off valve for a system such as a supercharger, as the supe rcharger is always producing boost. I realize that many people do use a blow off valve with superchargers, but it is indeed hard on the blower. I highly doubt that any supercharger manufacturers would warranty their blowers if they knew that the customer was using a blow off valve. Bob
A Bypass valve is always going to be discharging the boost until the engine goes to near zero vacuum, and the valve closes. This is critical because a supercharger is belt driven and is always producing boost. When you are driving, say in traffic and you let off the gas, that boost will get stacked up if you don't have a bypass valve. That stacked up boost will have no where to go but push back against the blower or find a weak spot in the plumbing.
A blow off valve blows off the boost at a set psi. A blow off valve works great for a turbo system, which typically doesn't produce any measurable boost until the engine is loaded and producing some exhaust velocity. You don't want to use a blow off valve for a system such as a supercharger, as the supe rcharger is always producing boost. I realize that many people do use a blow off valve with superchargers, but it is indeed hard on the blower. I highly doubt that any supercharger manufacturers would warranty their blowers if they knew that the customer was using a blow off valve. Bob
10-27-2007, 08:44 AM
#6
Team Owner
The ProCharger Proflow bypass valve is always going to have a slight leakage. We don't normally see the leakage to be significant enough to alter the amount of boost the blower produces. We've only had one faulty valve that I can remember. We replaced it and picked up two pounds of boost on a V6 Mustang kit.
A Bypass valve is always going to be discharging the boost until the engine goes to near zero vacuum, and the valve closes. This is critical because a supercharger is belt driven and is always producing boost. When you are driving, say in traffic and you let off the gas, that boost will get stacked up if you don't have a bypass valve. That stacked up boost will have no where to go but push back against the blower or find a weak spot in the plumbing.
A blow off valve blows off the boost at a set psi. A blow off valve works great for a turbo system, which typically doesn't produce any measurable boost until the engine is loaded and producing some exhaust velocity. You don't want to use a blow off valve for a system such as a supercharger, as the supe rcharger is always producing boost. I realize that many people do use a blow off valve with superchargers, but it is indeed hard on the blower. I highly doubt that any supercharger manufacturers would warranty their blowers if they knew that the customer was using a blow off valve. Bob
A Bypass valve is always going to be discharging the boost until the engine goes to near zero vacuum, and the valve closes. This is critical because a supercharger is belt driven and is always producing boost. When you are driving, say in traffic and you let off the gas, that boost will get stacked up if you don't have a bypass valve. That stacked up boost will have no where to go but push back against the blower or find a weak spot in the plumbing.
A blow off valve blows off the boost at a set psi. A blow off valve works great for a turbo system, which typically doesn't produce any measurable boost until the engine is loaded and producing some exhaust velocity. You don't want to use a blow off valve for a system such as a supercharger, as the supe rcharger is always producing boost. I realize that many people do use a blow off valve with superchargers, but it is indeed hard on the blower. I highly doubt that any supercharger manufacturers would warranty their blowers if they knew that the customer was using a blow off valve. Bob
Thank you for the "ABSOLOUTE" definition to using a BOV as opposed to a BPV(ByPassValve) on a SuperCharger!
And why it is necessary for a TT or ST system needs a BOV and not a BPV!
I am going to keep this and archive it in my files! and share again if this subject comes up! (W/Your permission of course)
Thanks,Matt
10-27-2007, 11:02 AM
#8
Race Director
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And why it is necessary for a TT or ST system needs a BOV and not a BPV!
BOVs also called waste gates are calibrated to open at a predetermined psi. They are usually controlled by spring pressure and you can change you maximum boost level by changing the springs.
You can also install a boost controller that lets adjust the boost with the turn of a ****. Up to the maximum preset boost set buy the waste gates.
10-27-2007, 12:51 PM
#9
Drifting
Most turbo setups use a bypass valve just like the centrifugal SC kits, and they use it for the same reason. The bypass valve and blow off valve are therefore one and the same. Some PD blowers use a bypass valve to prevent boost when not wanted, and to keep the unit from overheating.
A pop off valve is used to limit boost mechanically for safety or to allow a sanctioning body to enforce boost limits. These are rarely used on street cars.
A wastegate is a turbo only device which regulates boost by controlling flow to the turbine.
Long story short, a turbo blow off valve and a bypass valve are really the same thing. They can and are used on centrifugal setups, mostly for that ricer sound.
A pop off valve is used to limit boost mechanically for safety or to allow a sanctioning body to enforce boost limits. These are rarely used on street cars.
A wastegate is a turbo only device which regulates boost by controlling flow to the turbine.
Long story short, a turbo blow off valve and a bypass valve are really the same thing. They can and are used on centrifugal setups, mostly for that ricer sound.
Last edited by FRCTony; 10-27-2007 at 12:56 PM.
10-27-2007, 07:34 PM
#10
Melting Slicks
Thread Starter
How bad is it leaking?
It should not be hard to fix the Bypass valve it's only a diaphram operated by Vacumm and B@@ST!
Do you have enough Vacumm to operate it at idle to keep it open and then under B@@ST to push it closed or have you checked it by taking it off the Vette and bench testing it?
Because if it is bad it will be bad at idle too or it should be if it is failing to hold Vacumm or B@@ST!
Call ProCharger and ask them what they think or if they have a remedy!
BOV are good but I haven't heard of one on a ProCharger but would be curious to see if any have used them and with any success!
Thanks,Matt
It should not be hard to fix the Bypass valve it's only a diaphram operated by Vacumm and B@@ST!
Do you have enough Vacumm to operate it at idle to keep it open and then under B@@ST to push it closed or have you checked it by taking it off the Vette and bench testing it?
Because if it is bad it will be bad at idle too or it should be if it is failing to hold Vacumm or B@@ST!
Call ProCharger and ask them what they think or if they have a remedy!
BOV are good but I haven't heard of one on a ProCharger but would be curious to see if any have used them and with any success!
Thanks,Matt
10-27-2007, 08:32 PM
#11
Le Mans Master
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10-27-2007, 09:43 PM
#12
Former Vendor
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Hi Guys,
First off, I had a few drinks at dinner so grammer and spelling not so good. Also, I am not going to contradict or dispute anything Bob @ EPP said. The purpose of this post are things that I have learned about DV's (Diverter Valve or bypass type valve) when it comes to Audi/vw Porsche Turbo applications. Much of this knowledge I have applied to Corvette FI with all sorts of real world testing on my personal D1 Z06 and having logged thousands of miles on all kinds of valves.
Most of the SC/Turbo kits out there come with a POS Bosch plastic diaphram based DV. Weak springs, rubber internal prone to tearing at low psi. Also understand that I am dealing with alot more boost than most everyone would ever see here...sometimes 25 psi on stage 3+ builds etc...
This is where the bosch dv's tear
This is what we replace them with...All CNC, piston driven, beefy spring, nthing to tear or leak due to the double o-rings...
Common SC applications...
Valve is still open under idle and part throttle etc... Cleaner and crisper reaction due to the straight piston motion of the cnc internal.
In OEM applications where the DV is plumbed back into the system after the MAF, you should not use a BOV (Atmospheric valve) because the maf has already meter the air and the ecu thinks it is still in the system when it dumps fuel. If the air is not there, pig rich, misfire and maybe a slight shudder.
BOV's, if you want to run a BOV in a SC application, it needs to be setup so it unloads during part throttle or it will back up the system and drang the motor down... Also, man things factor into how a BOV will work under idle. Most valves can be loosened up a bit... My most popular valve the HKS SSQV setup is usually closed on idle however i have literally 10k miles with that valve with zero d1 issues, leaks or any problem and had it inspected recently and was all good... Also, many guys here have them with no reports of problems either other than my car sounds like a jet. A SSQV sounds sweet upto 12 psi, over that it is to much for my ears...
Whichever direction you guys want to go, I have everything in stock ready to ship... PM for more details...
Brian
First off, I had a few drinks at dinner so grammer and spelling not so good. Also, I am not going to contradict or dispute anything Bob @ EPP said. The purpose of this post are things that I have learned about DV's (Diverter Valve or bypass type valve) when it comes to Audi/vw Porsche Turbo applications. Much of this knowledge I have applied to Corvette FI with all sorts of real world testing on my personal D1 Z06 and having logged thousands of miles on all kinds of valves.
Most of the SC/Turbo kits out there come with a POS Bosch plastic diaphram based DV. Weak springs, rubber internal prone to tearing at low psi. Also understand that I am dealing with alot more boost than most everyone would ever see here...sometimes 25 psi on stage 3+ builds etc...
This is where the bosch dv's tear
This is what we replace them with...All CNC, piston driven, beefy spring, nthing to tear or leak due to the double o-rings...
Common SC applications...
Valve is still open under idle and part throttle etc... Cleaner and crisper reaction due to the straight piston motion of the cnc internal.
In OEM applications where the DV is plumbed back into the system after the MAF, you should not use a BOV (Atmospheric valve) because the maf has already meter the air and the ecu thinks it is still in the system when it dumps fuel. If the air is not there, pig rich, misfire and maybe a slight shudder.
BOV's, if you want to run a BOV in a SC application, it needs to be setup so it unloads during part throttle or it will back up the system and drang the motor down... Also, man things factor into how a BOV will work under idle. Most valves can be loosened up a bit... My most popular valve the HKS SSQV setup is usually closed on idle however i have literally 10k miles with that valve with zero d1 issues, leaks or any problem and had it inspected recently and was all good... Also, many guys here have them with no reports of problems either other than my car sounds like a jet. A SSQV sounds sweet upto 12 psi, over that it is to much for my ears...
Whichever direction you guys want to go, I have everything in stock ready to ship... PM for more details...
Brian
10-27-2007, 11:49 PM
#13
Burning Brakes
I questioned a possible leaking bypass valve with a procharger tech before. He told me the best way to check for any kind of a problem was to remove the bypass valve and insert a (D-Cell battery) into the hose and go out and smash the throttle. He said it wouldn`t hurt the blower or the motor. Go figure he was right I didn`t have a bypass valve issue.
Still considering upgrading mine over the winter.
Still considering upgrading mine over the winter.
10-27-2007, 11:57 PM
#14
Melting Slicks
Thread Starter
This is the better version of what is bad on my set up. I am leaning towards replacing the bypass valve with this.
Last edited by JeremiahsC5; 10-28-2007 at 12:01 AM.
10-31-2007, 02:55 AM
#15
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Hi,
I use an SSQV style blow off valve from HKS, that is closed at idle without any problems on a P600B and P1SC installation on C4 and C5.
Both systems work with MAF. On the C5 - the throttle blade area from ETC has to be adjusted with EFIlive or HPtuners especially if a ported one is used, to prevent overcorrecting the idle by the PCM. No issues on the C4 except the 1 PSI higher boost without leaking.
Regards
Marco
I use an SSQV style blow off valve from HKS, that is closed at idle without any problems on a P600B and P1SC installation on C4 and C5.
Both systems work with MAF. On the C5 - the throttle blade area from ETC has to be adjusted with EFIlive or HPtuners especially if a ported one is used, to prevent overcorrecting the idle by the PCM. No issues on the C4 except the 1 PSI higher boost without leaking.
Regards
Marco
