ok got all my issues with my car sorted out after zfr install. one little thing. when i start boosting to 23psi i hear a turbo fins slapping the air sound for a second, then it goes away. is that normal? doesnt do it in second, does it in 3rd, dont know about 4th. i looked up on youtube and saw one video with a regal zfr that does the same.

here is a vid of what it sounds like except mine is shorter and does it earlier

 

Mine does it in 4th only. I've only just realized in the last week or so though.

 

I checked again and mine actually does it exactly like the video. what is that? im wondering if the bpv is being pushed open and letting come of the boost hit back into the compressor wheel fins making that noise. cause it doesn't do it on lower boost, just high. and only for a bit then it stops.

anyone else have any insight on this? im getting bpv in a week or so from zzp, ill see if that makes a difference with block off plate on bpv hole.

 

Ya idk it's weird. Looking at the vid and what not mine seems to do it right along the same rpms.

 

Mine does it as well

 

Who's doing your tuning. Mine does not do this at all.

 

I doubt this is a tuning issue. Not everything comes down to the tune like Matt from zzp once gave everyone one crap for on here.

 

Actually a tune can cause this if you don't know how to tune the PID tables for boost, the ecu can be fighting the throttle plate and cause this. So yes, it can be the tune.

 

Well I'll talk to trifecta and see what's up

But was just saying it could also be something else. I had this happen really bad when I had a large boost leak as well a few weeks ago

 

OP how much boost you are running?

 

Sounds like the thing is hitting its surge line on the compressor map

"To simplify, on-boost surge is too much boost too early. However, this doesn't really define it properly. Surge is due to high exit mach numbers at the impeller so that for that given compressor wheel profile, the slip losses at the boundary layer lead to flow reversion that cascades in a resonant frequency, eg cha cha cha"

How big is your intake piping and IC piping?

 

3" intake 2.5" ic piping.

 

You guys using boost controllers or is it ECU controlled stuff? Just seems like this turbo is on the threshold for the surge line on the LNF.

 

Ecu controlled.

 

ECU controlled, the throttle blade most likely isn't open enough for the amount of air the turbo is pushing like someone already said

 

Ah the woes of drive by wire.

 

23 psi

 

is there any way to make throttle blades open more to see if that solves it?

 

Gotta take the bad with the good