Boost leak coming from the FPR vacuum line?

DynamiteBlues

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I'm currently running a paxton setup and at the same time i switched from FRPP hot rods to my stock cams, I found my self unable to get out of vacuum. At WOT i'll hit maybe 5" mercury, sometimes even more vacuum at wot. This is causing the diverter valves(bypass valves) to never fully shut, so all of my boost is getting recirculated rather than digested. Even part throttle when they normally let a whoosh out during shifts, they are now no longer making noise since they won't close all the way. I did take the valves off and test them and they seemed perfect, no leaks, and the piston was sealing perfectly. After Boost leak testing the piping of the actual blower kit, as well as the vacuum lines separately, the only place that was digesting(or leaking) any air was the FPR vacuum line. This line also runs to the brake booster & somewhere out of my vision toward the back of the block. This FPR line is the line that both bypass valves are T'd into, as well as my boost gauge. Is this line supposed to digest air? i thought it you tried to blow into it it would stop you. Any one ever have a leak start here ? if someone has a T here also (which i know many do) would someone ming blowing into the T off your FPR line and telling me if it will digest the or if it stops you ? Where could it possibly be leaking from?
 

PNR Welding

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I'm currently running a paxton setup and at the same time i switched from FRPP hot rods to my stock cams, I found my self unable to get out of vacuum. At WOT i'll hit maybe 5" mercury, sometimes even more vacuum at wot. This is causing the diverter valves(bypass valves) to never fully shut, so all of my boost is getting recirculated rather than digested. Even part throttle when they normally let a whoosh out during shifts, they are now no longer making noise since they won't close all the way. I did take the valves off and test them and they seemed perfect, no leaks, and the piston was sealing perfectly. After Boost leak testing the piping of the actual blower kit, as well as the vacuum lines separately, the only place that was digesting(or leaking) any air was the FPR vacuum line. This line also runs to the brake booster & somewhere out of my vision toward the back of the block. This FPR line is the line that both bypass valves are T'd into, as well as my boost gauge. Is this line supposed to digest air? i thought it you tried to blow into it it would stop you. Any one ever have a leak start here ? if someone has a T here also (which i know many do) would someone ming blowing into the T off your FPR line and telling me if it will digest the or if it stops you ? Where could it possibly be leaking from?

Hey were from the same area, where at are you located?
Who did your work on your car?
As far as the FRPS vacumn lines, they go to the back of the intake.
If you blow into that line you will be blowing through the intake into the piping/blower.
If you cant figure it out, bring it by the shop I work at and ill find it.
 

erat

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I just installed hot rods and I now have a vacuum problem. I think it will get looked at next week, I will post what is happening.
 

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