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-   -   turbo comperser surge (https://www.scoobynet.com/general-technical-10/855725-turbo-comperser-surge.html)

happydude303 16 October 2010 05:39 PM

turbo comperser surge
 
what are the signs of this how would i now if i have this any help would be great cheers dudes

djandyg 16 October 2010 08:53 PM

sounds like kind of fluttering sounds...

....here is a vid of fairly extreme case..

http://www.youtube.com/watch?v=nCj6Spwl1CU

happydude303 17 October 2010 11:19 PM

but the flutring sound is just the waste gate i take it its the nasty sound in between that

sc_sjo 18 October 2010 06:05 AM

Wastegates do not flutter (that you'd hear). No such thing as 'wastegate chatter'.

happydude303 18 October 2010 11:11 AM

ok so i have just had my harvey smith up pipe fitted to my 20g and also a samco type turbo indutcion pipe which is the right size i.e 56mm but the air inside are bigger then standard, i have had it mapped and is running the same boost as before 1.6 bar but now when it in 4th 5th or 6th with half to full throtle i get the fluttring noise my mapper has told me this is due to the induction pipe

Big 'D' 18 October 2010 12:17 PM


Originally Posted by happydude303 (Post 9661756)
ok so i have just had my harvey smith up pipe fitted to my 20g and also a samco type turbo indutcion pipe which is the right size i.e 56mm but the air inside are bigger then standard, i have had it mapped and is running the same boost as before 1.6 bar but now when it in 4th 5th or 6th with half to full throtle i get the fluttring noise my mapper has told me this is due to the induction pipe

The size of your induction pipe does play a huge part in compressor surge, what year is your car? Does the samco intake hose pass under the intake manifold, if so then try fitting a 57mm alloy pipe joiner to act as a restrictor where the samco pipe widens to mate with the other pipe that goes to the filter. This should greatly reduce or even stop the flutter altogether, you may have to fit a piece of silicone hose around the 57mm pipe joiner to get it to fit snug into the 76mm end of the pipe.

Cheers Iain

happydude303 18 October 2010 01:17 PM

ill take a picture but the pipe is for a version 4 which is what my car is but my mapper tell sme this is not comperesion surge but ill take some pitc s of how this is fitted and also try and get a video on here today with the noise that my help

happydude303 18 October 2010 01:25 PM

[IMG]http://i226.photobucket.com/albums/d...2/dyno3003.jpg[/IMG]


the piece of metel pipe is 76mm

happydude303 18 October 2010 01:25 PM

[IMG]http://i226.photobucket.com/albums/d...2/dyno3001.jpg[/IMG]

Shaun 18 October 2010 01:27 PM

Surge is noticeable by a fluttering noise when ON boost, which will normally be evident within a specific rev range..... at the point that the engine cannot consume the air that the turbo is trying to push through it (iirc). It can physically be seen by looking at a boost gauge during the same event. You will see the gauge needle rapidly oscillating.

Big 'D' 18 October 2010 01:30 PM


Originally Posted by happydude303 (Post 9661963)
ill take a picture but the pipe is for a version 4 which is what my car is but my mapper tell sme this is not comperesion surge but ill take some pitc s of how this is fitted and also try and get a video on here today with the noise that my help

Ok on your intake pipe is the hole on top of the red silicone turbo intake pipe blocked off? What you have described does sound like compressor surge so it would be worth trying the smaller pipe joiner 57mm or even 60mm where the red and blue pipes join in your picture and see if the surge goes away or is reduced.

Cheers Iain

happydude303 18 October 2010 01:36 PM

yes that hole is block off by a red rubber bung of some type i woudl liek to say my boost gauge has allway flutter about becuase i think it broke but on the pc when it is plug in it allway hits 1.6 bar no less now moer and on the dyno its the same

happydude303 18 October 2010 01:36 PM

[IMG]http://i226.photobucket.com/albums/d...2/dyno2002.jpg[/IMG]

happydude303 18 October 2010 01:37 PM

im about to take it out and try and record the noise be back soon witha vidoe link p.s if it was compersion surge woudl the car not be behaving weird

Shaun 18 October 2010 01:39 PM

According to that boost plot there does not appear to be a surge issue.

happydude303 18 October 2010 02:48 PM

http://s226.photobucket.com/albums/d...t=SDC10475.mp4

happydude303 18 October 2010 02:49 PM

here a link to a quick test please note this has only been done for a test i do not recomend that you try this at home and this does not have any thing to do with scoobynet , does that cover me you can hear it half way through the vid and near the end

eggy790 18 October 2010 03:32 PM

ive got this exact same noise on my vf48 in 4th 5th and 6th on full throttle, always in 5th and 6th as the turbo is coming on and 4th on uphills..

i need to get mine checked too, willl be keeping my eye on this thread.

sc_sjo 18 October 2010 03:35 PM

It is surge and it is typically that it happens in the higher gears due to increased load... Compressor surge occurs when the turbocharger is running at a pressure ratio too high for the amount of air the engine is consuming.. It's not as simple as which 'side of the line' you're at as every turbo model behaves differently on every different spec engine..

Ultimately it's a sign of a mis-matched overall spec and the typical bodge-it workaround is to adjust the boost control to drop the boost until it stops surging at that load point.

happydude303 18 October 2010 03:41 PM

dam funny it only started to do since fitting a up pipe to my rcm headers and a autobann turbo induction pipe the boost has not changed bu then in stead off dropin of boost at 5800 rpm it holds all the way at 1.6 bar to the end of the revs so im thinking it may well be this indutcion pipe

sc_sjo 18 October 2010 03:43 PM


Originally Posted by happydude303 (Post 9662191)
dam funny it only started to do since fitting a up pipe to my rcm headers and a autobann turbo induction pipe the boost has not changed bu then in stead off dropin of boost at 5800 rpm it holds all the way at 1.6 bar to the end of the revs so im thinking it may well be this indutcion pipe

If they're the only two things you've changed then one of them is most likely the cause. The bottom line is your engine isn't flowing as much air at one point (rpm) that it used to before. I doubt it's the intake pipe so would be looking at how the up pipe has changed the flow characteristics of the engine around the point of surge.

eggy790 18 October 2010 03:50 PM

is it harmful to the turbo or car at all? it doesnt bother me too much as if the car is being floored , ive normally given it beans in lower egars so by the time i hit these gears it doesnt cause a problem. its only when cruising and using it as an everyday car that i notice it.

sc_sjo 18 October 2010 03:51 PM

It can break turbos yes, which in turn can break engines.

happydude303 18 October 2010 03:51 PM

well it a havey smith up pipe so maybe the map needs tweaking again im going back to my mapper tomorrow to get him to plug in i was thingk my wrx heads but then the case is the same as the sti

eggy790 18 October 2010 04:04 PM

i best get mine looked at soon then, cheers

2.5STI 18 October 2010 05:14 PM

ive just had a engintuner 2.1 fitted and mapped with a vf43...

i get chatter when i let off and it comes from the filter.

and like you when on full boost in high gears it chirps... like the compresor surge video posted earlier. It gets hesitant at times when its doing it but generally it holds boost.


if this is bad for your engine please let me know as ive already spent 6 k and dont want it going bang.

eggy790 18 October 2010 05:20 PM

yeah as above i just thought it was going a bit hesitant to save itself from damage rather than causing it, i think i'll need the map looking at again.

Big 'D' 18 October 2010 05:39 PM

Where the 76mm hose joiner is remove that and fit a smaller one either 57mm or 60mm (I would get and try both) and the surge will be greatly reduced or even stop, once the smaller pipe joiner is in place you will be able to decide if you have gone too small or not small enough by seeing how the turbo responds or if the compressor surge is still there. This does work and saves you dropping boost.

It is easier and cheaper to match the flow of your intake to the exhaust than it is to match the exhaust to the intake.

Cheers Iain

PS. (unrelated but some will get it) Looks like I am not the only one with a high IT :D

angry_boy 18 October 2010 05:52 PM

:lol:;)

happydude303 18 October 2010 06:20 PM

thats not a joiner it was a bit of metal pipe which was just lying about which just so happend to be the right size to fit in both bits of silicone pipe so where can i get this joiner from dude any links to some good places cheers


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