Hey guys, not too sure where this belongs so mods please move to where appropriate.

I recently took my St205 for a long drive (1300km) and as we went along I discovered some noises that weren't apparent during my regular city driving.

Main one was a fluttering sound while building boost at high speed (100+) in high gear (4th or 5th) as the boost grew it sounded like the turbo wasn't spooling correctly, or the waste gate was at its limit. Anyone had similar experiences?

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Once there was nothing, then it exploded.

do you have a stock turbo or any other modifications?

What steve said - it sounds like either compressor surge or you can get a similar effect with a part throttle acceleration in a high gear. The st205 dump valve can also make some odd noises in these situations.

1) let us know what mods you have (mods to turbo and associated systems normally increase liklihood of surge.)
2) check your dump valve if a std unit to see if it has split or is damaged.

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JP
GT4DC Treasurer

Grey St185 RC
Silver BMW E46 M3
Multicolour yawn Honda VFR400
Silver Honda Civic Type-R

its only basically modified, SSQV and Pod filter.

Stock Turbo

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Once there was nothing, then it exploded.

Have you fitted a decat pipe?
Do you have standard exhaust?

Can get a "flutter" sound when backing off under hard acceleration.

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Vice Chairman
1990 White UK Celica ST185 - Project DTM
1997 Cream BMW R1200C (as seen in James Bond "Tomorrow Never Dies")
2005 Jaguar X-type 3.0 Sovereign AWD Automatic
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Is it a brief spool up type noise or does it persist for a while until the revs raise a little bit

It's probably a little bit of surge creeping in if it lasts for a few seconds.

ah forgot to mention, after market exhaust but the cat is still there.

The flutter is consistent during full throttle in high gear at high speed

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Once there was nothing, then it exploded.