Anyone getting flutters with the metal bpv on our cars?
I get some flutters with the bpv... I'm worried if this is turbo surge...

 

That "flutter" is just your heart going pitter-patter because the car is so damn fast.....

 

I'm interested to know everybody's input as well. I think I'm getting "flutter" as well, but I also have an AMS SRI. Only happens when I hit peak boost at around 22-24psi, but sometimes it does have a weird flutter sound.

I heard it with the stock bpv, but after I got an Evo X bpv, some of it was still there, so I assumed it was ok (first turbo car). Now I've been getting paranoid, reading that some Evo X owners have bad luck with their stock bpv when they're above 24psi. Probably me just being paranoid though idk

 

How often are u getting it, and are u shifting or in normal cause I remember when I would brake hard and have to speed up again I would get flutter

 

if it's happening at peak boost, you may have a compressor surge issue. bov "flutter" is usually something referred to by people under light boost throttle lift-off conditions.

under full boost with the pedal depressed, there should be no bpv action whatsoever.

letting off the pedal at full boost should give one quick whoosh sound.

can you be more specific about when and how it is happening and maybe we can help better. also, what tune are you running with the ams intake?

 

OP doesn't gave ams intake

 

I only get it about once a month. It happened twice so far.
It happens when I'm in low rpm/low boost, never happens when I'm in full boost.
I'm running GST v2.5 with boost pill with automatic normal mode

 

i get it under lower RPM "low boost".... always between 2000 and 2500 RPMs during throttle lift...

doesn't happen every time, only sometimes. Haven't quite figured out the exact condition to reproduce it at will... I normally get a "chuuuuh" when accelerating and I lift in that RPM range.

If I'm steady state cruise in that RPM range i get no sound when i lift... as to be expected

It's not a major problem, IIRC.

 

That's exactly what happens to me. I can't get it to reproduce it when I try.
Never happens under high boost. I'm wondering if I'm hurting the single scroll turbo... maybe they put a plastic bpv for a reason...

 

sorry for the confusion, i was talking to exyia since he mentioned the sri and peak boost, which is much more likely compressor surge and more dangerous than a little light-throttle flutter.

the "fluttering" is more or less the valve trying to release like its supposed to but since there's such little pressure and the pedal is lifted from a light accel or cruise position there isnt much pressure so it lets off whats there then closes the valve then a bit more then closes etc, you get the picture. i wouldnt be worried.

 

I dont have a X however I do have the IX and i get the same thing around 23 PSI, but ill be cruising and have to go up a hill and ill hear it a little bit and whenever im in a higher boost range.....now with that being said i can reproduce it at will and now that it isnt -10 or more it hasnt really been doing it, could just have been an overboost issue due to cold weather (live in alaska)
but i would deff like to know what is going on with that, going to pick up a X for the wifey and would like to know as much as possible before i do.

 

sorry to cause confusion, and sorry to hijack the thread a bit

but thanks a ton for bringing this to my attention. I google'd around about compressor surge but couldn't find any good material. What is general cause and effect of this?

I double checked my lines and they seem good, just a little loose. Because of the different angle from the evo x bpv, the T-hose that connects to my AEM boost gauge sometimes pops off under high pressure. I'll have to rearrange it so the hoses aren't so windy and I'm guessing that will fix it

but I'll definitely mention the compressor surge to my tuner, I was planning to stop by his place soon anyway. We're both learning the RA platform as we go. Thanks!

 

if a hose is coming loose, or even worse completely off, in the bpv or wga routing then the valve may not be opening at all. this means that the compressor is continuing to spin and push more air and is slamming it into the closed throttle plate which, in turn, will cause air to back up in the system very quickly to the point where it is actually bouncing back and creating a "reverse flow" effect and trying to force the turbo to spin backwards. this can cause major issues including very rapid failure of the turbocharger.

you can also try looking up the phrase "turbocharger cavitation" in google for more information if simply searching for compressor surge isnt yielding enough results

it is very highly recommended that you find another hose to tap into for your boost gauge as tapping into the bpv line has been shown in a few other mitsu evo/ra applications to cause issues as well

 

Ok i've been able to replicate the problem somewhat.

When I'm at low boost and the tranny upshifts and I lift off of the throttle, then the bpv flutters.
Let me know if you guys can replicate it too.

 

i think ur giving too much throttle at too low of an rpm, ive had this happen to me before