turbo flutter

rising son · February 16, 2012, 12:14:52 AM

how do i get this sound?, have a bov fitted at the moment but prefer the flutter noise... any ideas folks?

Skifledanabit · February 16, 2012, 01:01:56 AM

The flutter is a wastegate isn\'t it?

rising son · February 16, 2012, 01:20:39 AM

im sure its cause by the compressor wheel on the turbo spinning back in the opposite direction... correct me if im wrong?

batman · February 16, 2012, 05:00:58 AM

the chatter to which you reffer my friend is air feeding back to hit the turbo when you change gear its called many things but if its not set up right turbo stall as its called isnt good unless you have a twin scroll turbo to allow the air to pass back without slowing the turbo .
a dumpvalve is installed to allow the air presure between gears to escape hence the woosh .
if you dont run a dump valve on a standard system the air has no wehre to go and goes back to the turbo as it turns its makes that chatter .
so my advice is fit an aftermarket turbo with a twin scroll inlet remove your dumpvalve and it will chatter all day long without slowing the car .

this is the gt 35r i have on mine with twin scroll

note the extra holes at the inlet allowing air to pass back without slowing the compressor wheel

m1tch · February 16, 2012, 07:42:46 AM

Turbo flutter on the turbo on the left = ok, turbo flutter on the right = bad

the hat · February 16, 2012, 07:48:43 AM

The standard turbo on a turbo II makes no noise really it won\'t sound like the nissans etc that you want it too sound like also the plunger style afm snaps closed when this happens giving the excess boost pressure nowhere too go and makes the car jerk violently

stylus350 · February 16, 2012, 08:11:02 AM

I have done over 50k on various turbo\'s with no DV and they still had no issue. None if them twin scroll. The net is full of advice from people with no personal experience of things they still feel qualified to comment on.

edit - I mean 50k on one turbo I have done many many more miles on not dv set ups in total.

edit 2 - none of my experience is FC specific but can\'t see what difference that would make.

stylus350 · February 16, 2012, 08:14:44 AM

Quote from: rising son;812465im sure its cause by the compressor wheel on the turbo spinning back in the opposite direction... correct me if im wrong?

The wheel does not spin backwards but it is the sound of the air pushing back past the wheel.

the hat · February 16, 2012, 09:38:03 AM

Ere here stylus I\'ve never ran a dv untill my first fc due too the afm as described above and the large turbo above may be twin scroll but that has nothing too do with the compressor housing what Is being spoken about is called an anti surge housing

Grant Monkhouse · February 16, 2012, 09:55:03 AM

When referring to twin scroll that is the type of housing on the turbine side of the turbo. A ported shroud is what you are meaning to describe.

A turbo should be fine without a BOV and without a ported shroud, you will probably just get a slightly increased drop in rpms when changing compared to if you had a BOV and ported shroud.

rising son · February 16, 2012, 11:08:23 AM

ive read alot of comments over the years about this being a bad thing.... generaly thought and heard from tuners that this isnt realy the case, more of just a wide spread rumour.... although if you are saying i wont get the desired sound from the fc turbo then its pretty pointless i supose... never actualy found any evidence to confirm it being bad for the turbo... just a lot of hearsay.... any evidence wud be great though??, cheers so far

dthebuk · February 16, 2012, 11:17:19 AM

you can achieve turbo chatter in a number of ways.

Either relocate the afm so it\'s after the turbo, i think this will require a mappable ecu or at least some sort of uprated map.

Convert to a hotwire maf

Convert to an aftermarket ecu that allows you to remove the afm.

rising son · February 16, 2012, 11:40:38 AM

so im guessing just blanking off the BOV wont work then....

festa · February 16, 2012, 12:35:57 PM

I\'m running a standard (soon to be upgraded to hybrid) turbo with an RE ECU and mods to support it, I disconected the factory BOV as it was opening early due to the ECU running 0.9 bar boost, the turbo does really wind up now and gets abit of chatter on changeing gears.
Also isin\'t the noise caused buy the waste gate opening when you change gear, ie waste gate chatter.
There is a thread on here about running a BOV and it seams to be a matter of opinion, If I was to run one it would be a plumbed in one as the chatter noise is cool and BOV to air noise is not (in my oppinion)
Cheers

Grant Monkhouse · February 16, 2012, 12:50:25 PM

Wastegates are on the exhaust side of a turbo system so you don\'t get chatter, just an extremely loud exhaust noise as the wastegate opens

Sounds like this
http://www.youtube.com/watch?v=UF7kfoXrlyk&feature=youtube_gdata_player