How much fluttering noise is normal vortech
 

Since I've been driving the car more I'm questioning the loud fluttering that happens a lot while cruising. From searching this seems to be compressor surge and possibly the bpv not set correctly? It happens under light acceleration and sometimes in-between upshifts. These aren't the best videos to hear it but it's all I have for now.
Vortech V3 and Tial QRJ not recirculated btw.
Best video so far
https://youtu.be/si2lSrrxCIk

https://youtu.be/meGqayxjm0M

https://youtu.be/HjTmSG0Nmm0

It sounds very similar to this but only while driving at low rpms like 2200 cruising, more of a whistle https://www.youtube.com/watch?v=KtReC1-rZtA

So I bought a 370z with a stage 1 GTM kit and Tial QRJ bypass valve. The fluttering drove me nuts at the start. I contacted Tial and we took a vacuum reading. The spring I had seemed like the correct spec, but they sent me 2 other springs (one stiffer and one looser) to try. Each other spring made it worse. After awhile I found a couple guys that have the same setup and both said it's normal for them.

I don't have any good videos of the fluttering, you can sort of hear it at the start of this video though. It's definitely annoying, but now that I know it's normal it doesn't bother me quite as bad.. wish I could do something to quiet it up, it's already recirculated to the intake

https://imgur.com/gallery/YabPywU

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I have a Turbosmart Plumb Back (not sure if 32 or 38mm) routed back to the intake on my GTM Stage 1 kit, and I’ve never noticed any flutter. You can adjust spring preload and see if it helps the flutter.


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Man.. if you could find out the size, and maybe send me some pictures of it installed when you have time I would be so damn grateful. I'm pretty sure my QRJ is 38mm, if this is as easy as swapping to what you have in 38mm I'll be so unbelievably happy

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I’ll measure size when Im home later. Blue arrow shows the vacuum line routed up into the engine bay. Recirculated right into the air filter intake pipe as I’m sure yours is too.

Shoot me a message if you want!

https://uploads.tapatalk-cdn.com/202...a6b97d43ae.jpg


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