Boost Fluttering

[nizmokid]

I have had my r33 tuned and all is good but the on high boost the boost gauge flutuartes from 1 bar t0 1.2 bar.

I have a good deal of mods:

sm4 altronic

555cc nismo inj

HKS intercooler

Greedy rs BOV

Garrett 450hp turbo internal gated

mid mount ex manifold

oil cooler

ect.....

I am make 300rwkw on highboost

what could cause this boost spike/flutter. ...........wastegate or valve float or some thing.

or I might just turn the high boost down a fraction! and see what happens!!

[Pauly33GTS-t]

fix your blow off valve maybe it is wound up too tight.

[nizmokid]

or not enough

[Pauly33GTS-t]

yeah or that, I think that BOV placement could also be a factor, and also your turbo to afm pipe, what of these?

[nizmokid]

I have a K&nN pod in sealed box, with a custom cold air snorkle to feed cold air from the lower front bar.

No AFM now..... it has a straight 3" pipe from the filter to the turbo!

[Pauly33GTS-t]

i was thinking maybe the pipe you got from your turbo to your filter is possibly contributing to flutter maybe by its design, length, etc. this might be the case, someone with a bit more experience should give you a good answer, but most of the time its a blow off valve setting.

[Waldo]

hey i get the same problem! i have an rb20 with a td06 and all the goodies, i run a apexi power fc boost kit, and i noticed that when on ful boost (which is only 14psi) the needle on the gauge flickers like crazy it is like a big blur it moves that fast? and i dont have a blow off valve at all! with all custom pipe work, i cant seem to find what it is.

[180bfj20det]

Nizmokid, sounds like bad boost control. Check vacuum leaks, positive pressure piping.

Waldo, sounds like compressor surge.

[heller44]

Had a similar symptom on my car as well.. gain on the boost controller was turned up against the end stop, causing oscillating.

[J34]

Have you got any dyno run copies showing what the boost is eaxacty doing, that would probly make it easier to work out where the problem is.

[ahh 33 s2]

i read this thread jumped in my car and it started happening.

i got an avcr tuned less then a fortnight ago z32 afm custom piping and a stock turbo with no BOV at all. i presume if i had any leaks it would have been braught up when tuning, thats why i dont have a bov, had a cheap china one that was leaking.. is there a quick and easy and cheap way to fix???

[Brocaine]

I'd agree with bad boost control.

[Adriano]

What boost control are you running, sm4's have closed loop boost control, are you using that.

[Adriano]

300rwkw on 1.2 bar seems a bit high for a 450hp internal gated turbo?