notfub

iTrader: (4)

I have owned my classic for around 5 weeks now, however, during the last week I have noticed that the car produces the compressor surge / flutter noise when changing gear at boost. Now while this sounds fantastic, I'm wary of the fact that the VF turbo's don't like compressor surge and I could be doing more harm than good by leaving it as it is. Would the STI8 recirc dump valve be playing up and not actually dumping the unwanted boost? Can I test the recirc DV at all?

I'm new to scoobs but comfortable with mechanics so am not afraid to get my hands dirty if need be.

The car has a VF34 turbo, STI8 TMIC, Bob Rawle remap and STI8 Recirc DV plus the usual 3 port, Walbro, sports cat downpipe and HKS exhaust. It's running around 1.5 boost at peak according to my gauge.

turboDean

iTrader: (4)

The Vf34 is supposed to be one of the stronger more reliable of the VF series, mine always made the fluttering noise even with a VTA valve.
Really wouldn't worry about it myself.
My new turbo is a lot more noisey than the VF34

catalunya 172 ker

has it got an induction kit on it ? as when you have a bigger turbo and map ect... this can give the flutter noise as its running alot more boost than normal 1.5 bar of boost seems a good bit of boost, would not like to run anymore boost than that tho as if it has not been forged ect., it could give you problems in the long run depending how its used tho

The Stitcher

iTrader: (12)

sorry fella posted under my other halfs name didnt realise she was signed in

notfub

iTrader: (4)

It's running the standard airbox with a green panel filter at the moment. The last owner had the engine rebuilt by API after a MAF failure and then had the mapping and mods done after the initial run in. The engine has standard internals and has now done almost 25k since the rebuild.

I drive the car resonably sensibly for a 38 year old (yeh I know I'm too old for an Impreza), only enjoying the acceleration now and again when it's safe to do so. I don't rev the guts out of the car but it's taken me some time to get used to just how fast the revs rise (due to the lightened flywheel no doubt).

Just wanted to make sure everything is as it should be really as I don't fancy any large bills in the current climate.

Thanks for the advice

APIDavid

iTrader: (4)

Is it actually surging ? IE hesitating and being a bit misfire-y? Or is it just a noise.

The late series VF's are ok to run even without a dump valve and make a superb noise when compressor stall sets in on closed throttle. No need to worry about the turbo in that respect.

It is the older pre VF30's that I worry about in that situation.

David APi

Agents for:
Simtek, the most exciting new Ecu for years
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And of course; the well known APi Performance Exedy organic clutch

www.apiengines.com

01926 614333

KJD Mk1

iTrader: (3)

Love the flutter noise, just need some antilag to go with it

notfub

iTrader: (4)

Thanks for your comments David.

My initial post was relating to the noise to be honest but the car does hesitate a little when cold. For example, it doesn't feel smooth if holding constant revs in 3rd for instance. Not too bad, just not as sweet as it runs when warm. I've put this down to the fact that the car is far from standard and needs to be nice and warm for the map & mods to work efficiently.

As for antilag, don't tempt me

turboDean

iTrader: (4)

It's great fun, turn mine on the other day going passed a pub and some women almost fell off her seat outside

APIDavid

iTrader: (4)

Bloody hooligans !

Next you'll be wearing Burberry..............



David

Now we know why Kev got rid of the plastic thing - he was missing the 'flutter ' Poor lamb

KJD Mk1

iTrader: (3)

Nothing wrong with plastic cars David no need to be bitter just because the older generation cant get in them

BTW how are all the team doing? will have to call up for one of those Sat bacon butties soon

APIDavid

iTrader: (4)

We're all good thanks Kev, Nathan says hi!

Big Daz called an a few weeks ago lookin' at cars. Gave him a quick road test and off he went muttering about nutters up this part of the world.

You have to demonstrate a cars true potential no point otherwise.

See ya sometime. Butties as ever on a Saturday.

David and all

simb 2

iTrader: (3)

Will be speaking soon David, need to get the car in for an oil change, not that it's done much mileage since the last time

simb

APIDavid

iTrader: (4)

You've broken a leg or ankle or summat haven't you ??

Good Luck, David

simb 2

iTrader: (3)

Tell you all about it when I see you mate