Vacuum line routing ?'s
06-22-2008, 10:42 PM
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Vacuum line routing ?'s I have looked through the stickied thread but still have a few questions. I have a JGS 54mm bov, and a JGS 50mm Wastegate. The bov has one port on top
, the gate has 2 on the side. 
I plan to use a manual boost controller, but for now I just want to run on the gate spring, should I just run intake vacuum to the bottome port on the gate, and vent the top to atmosphere? Then when I hook up the boost controller, run the top port to the controller?
Second, is it normal for the BOV to be open about an inch at idle? it still builds boost, but just didn't seem right.
Thanks
Chris
, the gate has 2 on the side. I plan to use a manual boost controller, but for now I just want to run on the gate spring, should I just run intake vacuum to the bottome port on the gate, and vent the top to atmosphere? Then when I hook up the boost controller, run the top port to the controller?
Second, is it normal for the BOV to be open about an inch at idle? it still builds boost, but just didn't seem right.
Thanks
Chris
06-23-2008, 04:10 AM
#2
I don't want to say for sure b/c stuff that doesn't make sense happens... but, the BOV should be 100% closed at all times. If not, air that should be boosting into the engine will be escaping out of the BOV. It should be fully closed under WOT to let air flow into the engine and then open after WOT to release trapped air from between the turbo and TB.
On the Wastegate, again I don't know because the wastegates i've used have always had one top port and one side port but I would guess that the higher side port would be your 'top' port. For now with the manual boost controller, just run the boost source to the lower port of the wastegate. In the future, yes, run the electronic boost controller solenoid to the top-side port.
On the Wastegate, again I don't know because the wastegates i've used have always had one top port and one side port but I would guess that the higher side port would be your 'top' port. For now with the manual boost controller, just run the boost source to the lower port of the wastegate. In the future, yes, run the electronic boost controller solenoid to the top-side port.
Last edited by SStolen; 06-23-2008 at 09:43 PM.
06-23-2008, 09:39 PM
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Okay, got the wastegate figured out, but I took a closer look at the Bov and it is staying open all the time. I revved it up from the tb and watched it and it never moved, but when I pinched the vacuum line a little it went down. Do I need a stronger spring in the bov?
06-23-2008, 09:45 PM
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the wastegate uses the bottom port (closest to the v-band flange) the top port is for c02
the reason the blow-off is staying open is because you are building more vacuum than what the spring is rated for. yes a stiffer spring will work. but as soon as your at 0 vacuum it should be shut
the reason the blow-off is staying open is because you are building more vacuum than what the spring is rated for. yes a stiffer spring will work. but as soon as your at 0 vacuum it should be shut
06-23-2008, 10:26 PM
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Yeah, it shuts when the car is off, or even just pinching off the vacuum line. I have about 15lbs of vacuum at idle. I figured it would close when I got on it, but wouldn't that make it take longer for boost to build up? How do you figure out what spring to go with?
06-23-2008, 10:30 PM
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i have a 15lb in mine, but i am only pulling 6 to 8lbs at idle. double the springs up. dont stack them. one should fit inside the other
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06-23-2008, 10:35 PM
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hmmm okay, I will call the turbo shop tomorrow. Is it a matter of trial and error, or should I buy a spring the same pressure as my boost idle?
07-06-2008, 11:45 AM
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Yeah I actually added another small spring to the exsisting bov spring. Works almost flawlessly, opens about an 1/8'' at idle and shuts as soon as you touch the throttle. Wastegate seems to be working okay, I referenced it off the turbo housing. It is hits 7psi right off the spool but tapers down to about 5 or 6. Not sure if that is normal or not.
what springs are those? not the BOV spring--the lowering springs...DMS? 
07-07-2008, 08:10 PM
#13
its tuned for 8# but i hit 7# and some times it stays at 7# and some times it drops to 5#?
any one know what that might be? 