[Chris_506]

hi guys i just wanted to see if anyone could chime in and point me in the right direction with this issue, about a week ago i installed an ER charge pipe with a synapse bov. And i have been noticing that on lower rpms the bov releases boost great and it sounds nice and clear(specially after adding a jb4 two days ago) but on higher rpms like 5k and above it wont make the swooosh noise as if it wasnt releasing boost at all it makes a very brief psh sometimes it seems like it does it twice. For some reason i dont feel like it does it all the time but when it does it i feel a noticeable loss of power.

Anyone has an idea why it will release boost no problem on lower rpms but wont on higher boost? it seems like the vacuum lines are set up fine and all the clamps are on tight so im kind of out of ideas.

any help is appreciated and also i would like to wish everyone on the forum a very happy new years!

[335_MI6]

I'm guessing your auto?

[Chris_506]

Originally Posted by 335_MI6

I'm guessing your auto?

sorry, 6mt

[stratos_335]

It does it after 6500 rpm and it releases boost after changing gear and releasing the clutch. Sometimes there is a double woosh. I think it's not the Synapse BOV...

[tcw]

IIRC it is a JB4 feature to help reduce boost loss from shifting.

[Chris_506]

Originally Posted by tcw

IIRC it is a JB4 feature to help reduce boost loss from shifting.

whats IIRC? im sorry im just becoming familiarized with jb4, so its normal?

[tcw]

If I Recall Correctly

I have synapse BOV & JB4 as well. If I push in the clutch at 6500 there is a brief "psst" before the BOV closes holding boost. If I then shift to neutral and release the clutch it will continue to "psst" or if I shift the the next gear it will retain some of the boost.

When this first happened to be I did some research and IIRC there was a setting that controlled this on the JB4.

Originally Posted by SCSRe92

whats IIRC? im sorry im just becoming familiarized with jb4, so its normal?

Edit:

I think it is the "bogfix" in this picture.

[335aw]

If I Remember Correctly

HAHAHA apparently i had the tab open for a while and didnt respond until after you.

[Kalud]

Yes it's the bogfix feature that keep some psi during shift to make shifts smooth.

[Chris_506]

oh i see, as long as it is normal thats cool. I was just worried it may have been pushing air back in the turbos or anything like that. Also i been running map1 for 2 days all i have is a DCI, do you think thats good? or would 5 be a better map to run?

[E90Company]

Originally Posted by SCSRe92

oh i see, as long as it is normal thats cool. I was just worried it may have been pushing air back in the turbos or anything like that. Also i been running map1 for 2 days all i have is a DCI, do you think thats good? or would 5 be a better map to run?

Either one is fine to be running. Map 5 will probably give you a bit more power. Just always log, log, log.

[Chris_506]

Originally Posted by E90Company

Either one is fine to be running. Map 5 will probably give you a bit more power. Just always log, log, log.

Which brings me to my next question. How exactly do you log? sorry jb4 noob

[Jeff@TopGearSolutions]

If it doesn't release as much or at all when you shift at high RPM, these tunes have tendency to hold boost between shifts, which is normal.

If it doesn't release at all if you were to accelerate to 5000 RPM and just let off the gas then there would be a problem with it.

[E90Company]

Originally Posted by SCSRe92

Which brings me to my next question. How exactly do you log? sorry jb4 noob

N54Tech has a guide on exactly how to do it so check that out. Basically connect the USB cable to your laptop, download the JB4 interface software from that website, check which COM port your USB cable is running on through Device Manager on your PC and enter that into the JB4 program. After that turn on your car's ignition (Key in slot, start button pressed without pressing the brake to start it) and press connect in the JB4 program. Then just hit start log when you are ready, and floor the car in third gear from 2k to redline. Ideally a full third to forth gear log is best but a full third gear will be good enough. If you need any help setting it up or reading them you can PM me

[Chris_506]

Originally Posted by E90Company

N54Tech has a guide on exactly how to do it so check that out. Basically connect the USB cable to your laptop, download the JB4 interface software from that website, check which COM port your USB cable is running on through Device Manager on your PC and enter that into the JB4 program. After that turn on your car's ignition (Key in slot, start button pressed without pressing the brake to start it) and press connect in the JB4 program. Then just hit start log when you are ready, and floor the car in third gear from 2k to redline. Ideally a full third to forth gear log is best but a full third gear will be good enough. If you need any help setting it up or reading them you can PM me

i already have everything setup on my laptop i just wasnt sure where to start the logging but i will find a good road to do that and will do so this week, thanks alot for the help guys and as soon as i get some logs ill PM you maybe you can tell me what im looking at lol

[SKuo07]

Sorry to bump an old thread but I am running the Synapse as well with a 6mt and a PROcede and I have experienced the same thing as well. Shifting at low boost is fine but at WOT and higher boost I get a weird "double whoosh". I have been to their headquarters in San Diego to see if they can figure it out but they couldn't and said it was probably just the nature of the tune or had to do with how the car was closing the throttle. As far as I know it happens to everyone. Can anyone else shed some light on this?