Blow off valve or not?
Joined: Oct 2008
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From: Bay Area, California
i agree very old thread lol
the spring on the HKS is probably not suited for the s/c as we need a much softer spring on the s/c kits. remember, the bov will be purging air the entire time when you let off the throttle while remaining in gear. the rotrex is belt driven. You could try checking on your vacuum lines to make sure they are correct. As far as a re-tune, if the car isnt hesitating on partial throttle, i dont think its needed. The retune would be more of a drivabillity fix rather than power.
the spring on the HKS is probably not suited for the s/c as we need a much softer spring on the s/c kits. remember, the bov will be purging air the entire time when you let off the throttle while remaining in gear. the rotrex is belt driven. You could try checking on your vacuum lines to make sure they are correct. As far as a re-tune, if the car isnt hesitating on partial throttle, i dont think its needed. The retune would be more of a drivabillity fix rather than power.
my vortech sc kit has a tial 50mm bov and it sounds like rushing air when im not partial throttle or WOT. kinda annoying, but sounds bad ass when you hit boost and let that go off
i'm confused on your statement. i think any car, with boost and a bov, can rev in neutral or even in gear with the clutch in and still make the bov go off due to the vacuum pressure in the diaphram
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Joined: Jun 2007
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Huh? The bov is venting at idle, so as soon as you give the car a good twist of the gas the bov closes. Unless of course your not running a proper SC spring and its staying vented. It should close as soon as you apply a decent amount of throttle. You can induce that with your head under the hood and a quick flip of the butterfly. if you cant hear the BOV over the engine noise, put your hand over the end and feel the air evac on idle and then feel it go away when you apply throttle and then blow off. Go try it out.
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Joined: Nov 2008
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Originally Posted by t1mmy626' timestamp='1467506818' post='24007888
Sorry to dig this thread back up but i'm experiencing some issues after I installed my new BOV.
MY car currently has a kraftwerks supercharger on it running about 10psi. Originally I had tuned the car with the stock Bypass valve recirculating the air but just recently installed a HKSSQV BOV on the car and now it has a fluttering noise/ not enough air sucking in noise upon partial throttle when in neutral.
Also while driving in gear if i'm WOT or partial throttle there are no issues but as soon as I am off the throttle the fluttering noise will continue as the rpms decline in gear. My questions is do i need to get this retuned due now that I installed this BOV?
Thanks in advanced!
MY car currently has a kraftwerks supercharger on it running about 10psi. Originally I had tuned the car with the stock Bypass valve recirculating the air but just recently installed a HKSSQV BOV on the car and now it has a fluttering noise/ not enough air sucking in noise upon partial throttle when in neutral.
Also while driving in gear if i'm WOT or partial throttle there are no issues but as soon as I am off the throttle the fluttering noise will continue as the rpms decline in gear. My questions is do i need to get this retuned due now that I installed this BOV?
Thanks in advanced!
i agree very old thread lol
the spring on the HKS is probably not suited for the s/c as we need a much softer spring on the s/c kits. remember, the bov will be purging air the entire time when you let off the throttle while remaining in gear. the rotrex is belt driven. You could try checking on your vacuum lines to make sure they are correct. As far as a re-tune, if the car isnt hesitating on partial throttle, i dont think its needed. The retune would be more of a drivabillity fix rather than power.
Originally Posted by Memo6453' timestamp='1467507538' post='24007893
i agree very old thread lol
the spring on the HKS is probably not suited for the s/c as we need a much softer spring on the s/c kits. remember, the bov will be purging air the entire time when you let off the throttle while remaining in gear. the rotrex is belt driven. You could try checking on your vacuum lines to make sure they are correct. As far as a re-tune, if the car isnt hesitating on partial throttle, i dont think its needed. The retune would be more of a drivabillity fix rather than power.
my vortech sc kit has a tial 50mm bov and it sounds like rushing air when im not partial throttle or WOT. kinda annoying, but sounds bad ass when you hit boost and let that go off
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Joined: Dec 2009
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From: Miami
Originally Posted by Memo6453' timestamp='1467588613' post='24008305
Get the Turbo Xs Dual port. It fits well and has the option to VTA or recirc. Just change the spring out for the softer spring.
i use the Turbo XS one and i changed out the spring. maybe it wasnt required... i recirc mine though... i hate the hair dryer sound all the time
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Originally Posted by s2000Junky' timestamp='1467600554' post='24008425
[quote name='Memo6453' timestamp='1467588613' post='24008305']
Get the Turbo Xs Dual port. It fits well and has the option to VTA or recirc. Just change the spring out for the softer spring.
Get the Turbo Xs Dual port. It fits well and has the option to VTA or recirc. Just change the spring out for the softer spring.
i use the Turbo XS one and i changed out the spring. maybe it wasnt required... i recirc mine though... i hate the hair dryer sound all the time
[/quote]
Ahh i know now what "hairdryer" sound your referring to. I originally unplugged the recirc. hose on the stock bypass valve thinking i could just run it like but there was massive amounts of air shooting out during idle and it didn't seem right which is why I got the HKSSQV BOV instead and now it seems like it isn't compatible. I guess essentially I could just run the stock Bosch bypass valve VTA?
Joined: Dec 2009
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Likes: 17
From: Miami
Originally Posted by Memo6453' timestamp='1467603722' post='24008440
[quote name='s2000Junky' timestamp='1467600554' post='24008425']
[quote name='Memo6453' timestamp='1467588613' post='24008305']
Get the Turbo Xs Dual port. It fits well and has the option to VTA or recirc. Just change the spring out for the softer spring.
[quote name='Memo6453' timestamp='1467588613' post='24008305']
Get the Turbo Xs Dual port. It fits well and has the option to VTA or recirc. Just change the spring out for the softer spring.
i use the Turbo XS one and i changed out the spring. maybe it wasnt required... i recirc mine though... i hate the hair dryer sound all the time
[/quote]
Ahh i know now what "hairdryer" sound your referring to. I originally unplugged the recirc. hose on the stock bypass valve thinking i could just run it like but there was massive amounts of air shooting out during idle and it didn't seem right which is why I got the HKSSQV BOV instead and now it seems like it isn't compatible. I guess essentially I could just run the stock Bosch bypass valve VTA?
[/quote]
You could but if it's the plastic Bosch valve, I'd upgrade. I have a billet KW 25mm bypass valve I could sell if interested.