A few weeks ago I had a local member tune my car. I was GMS1 before. I got him to give me a very mild tune over gms1. I am only running 21 psi and only about 12 degrees of timing. The car works great and has a lot more power then before. At wot I am NOT getting or hearing any turbo flutter. But , if i am in a parking lot just slowly trolling along in 1st gear and at about 10 or 15mph and let off the gas. I hear a very faint turbo flutter. That is the only time I hear it si far. It doesnt do it in any other gear at all. I am wondering if this is at all normal and if it will cause my turbo to blow sooner then later ? Or is it fairly common and harmless in small amounts ?

I should note. That I am running the know. So i never heard the turbo or noise before maybe ? Maybe it was always there before. The day he tuned my car I installed the intake so he could tune for my kn. I am also NOT running the vac tank anymore if that AT ALL causes any of it, I broke it years ago by mistake ..

Under all other conditins and times my car works great and perfect. It now shreds my poor tires in 2nd gear. And even after a wot pull. I get and hear no flutter at all. Any thoughts ? Thanks

 

Well if you just installed the intake i would be guessing your hearing it from that probably check for shaft play just to be sure

 

It's cause of the vac tank delete. The vac tank stores vacuum to open bp valve quicker, without it it's slightly slower and at low load it ur car won't pull vacuum fast enough to open it on time. If u have a forge bpv make sure u have lighter spring in, it helps a lot. Otherwise u have to live with it

 

I am still running the stock bpv. Never touched at all. I am okay with the noise as long as it doesnt blow my turbo up or bend the blades. I just checked for shaft play and there is none at all. I just wanna make sure the noise is harmless after the vac tank delete ans the kn and my tune. Cause it like when i first installed gms1 all over again. Lol...

 

Am i okay to run 21 psi and my tune with no vac tank ? Or am i better off to re-install the vac tank. Cause its broke...

 

Your fine To be without it im running 23 psi and dont have it

 

yes ur fine with running no vac tank, its simply to help the bpv and for sound dampening. I run no vac tank on zfr on 28 psi.

 

So the small amount of turbo flutter i have now is no worry at all ? Like i say. It only happens in 1st while im coasting a few seconds later for a split second.

 

Flutter is fine, surge is bad and can cause damage.

 

Honestly.. I dont know the difference between the two ?? All i know is what i have is veey faint and doesnt happen all the time. Lol. I just dont want to hurt anything. I imagine it is a faint amount of flutter. But what is the difference between them ?

 

All these cars make the fluttering noise for the most part. It's normal don't worry about it. You should hear the solstice with a vacuum pump. it's even worse

 

If it's only happening in first it's just a symptom of a low boost. The k&n just amplifies the sound that was always there and you just couldn't hear it. As long as it isn't doing it in other gears I wouldn't worry about it. If it does and you feel power loss it's probably going into limp mode and there may be a code logged that isn't a cel. Usually a symptom of gms1ower tmap sensor wiring.

 

Surge is when ur at wot and ur turbo is trying to hit full boost and starts to flutter when gas is on the floor. Zfr do that a little at around 4-4500k rpm it's a pain to tune out. I got mine pretty well gone but still does it a little one in a while. Not enough to do damage

 

Did you get your 1st gear boost reduced as well with the tune? Could go with what he's saying up there about low boost

 

You'll know when it's surge, nothing like the flutter. With surge the car feels like it's misfiring and bucking and it's louder than flutter significantly.

 

Synaptic1 on Youtube has great videos demonstrating compressor surge:

And what some might THINK is compressor surge, but is considered 'flutter-dump':

 

Good examples.

 

They are good examples i think i get flutterdump sometimes

 

Yikes, I might be getting surge!

So, is it the spring on the BPV that I need to check?

The car cuts out sometimes between 5-6k, I thought it was possibly dirty intake valves. Got some seafoam to run through it, but haven't done it yet.

 

Seafoam doesnt really work for the lnf.

 

Great. Well, I am wondering now if it just needs plugs. Amongst other things...

 

If you want to clean your valves use the walnut blasting

 

So I get flutter dump a bit with my Forge BOV, also I find the let off totally annoying like its too easy in everyday traffic (I commute) So I thought about using a yellow spring. Now watching that video I definitely have that "issue" I quick flutter before full dump,

 

I only get it if i give it very light throttle but if i give it just a tad more it sounds like it should, i had it even with the stock bpv

 

I have the lighter spring in my Forge unit, and I def get flutter dump if I build boost and let off real quick. No big deal.