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Facelift Actuator Rod


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#1
c2wak

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I know this decat ticking has been done to death so I will keep this short.
I recently had mine retuned on the dyno and I'm impressed with the results which I won't disclose as it's not relevant. Speaking with the tuner about the decat wastegate noise and he seems to think by adjusting the actuator rod making it closed till more pressure is encountered would prevent the tick but would also increase turbo lag. Any comments?
Before I get slated I'm not a mechanic just going off what I'm told!
Really don't want to have to put cat back on just to hide a noise.

#2
T-800

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I know this decat ticking has been done to death so I will keep this short.
I recently had mine retuned on the dyno and I'm impressed with the results which I won't disclose as it's not relevant. Speaking with the tuner about the decat wastegate noise and he seems to think by adjusting the actuator rod making it closed till more pressure is encountered would prevent the tick but would also increase turbo lag. Any comments?
Before I get slated I'm not a mechanic just going off what I'm told!
Really don't want to have to put cat back on just to hide a noise.

The Wastegate is open by default as a safety measure on the FL car.

A turbo specialist told me this a while back and he says it’s to protect the engine from anything untoward happening with boost.

As you drive along and boost is required the gate is closed by vacuum applied to the actuator thus allowing the wastegate to close and boost built

I’d imagine if you ‘closed’ the gate by fiddling with the rod then the engine has no control over what it does and you’ll be creating boost in every situation even when it’s not needed, which can’t be good I’d imagine.

Older setups had a spring with a preset load that when exceeded with too much boost allowed the gate to open to bleed boost off.

The turbo specialist I spoke to said there is very limited info on these new KKK Borg Warner turbo setups at the moment, as they don’t tend to give much detail away.

Edited by T-800, 18 June 2018 - 05:47 AM.


#3
BenTTU

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This is purely my experience over the years with turbochargers, I haven't had the chance to play with a 8v fl turbo.

 

But all vacuum actuators close via a vacuum or even by electrical control, once engine has started. 

 

Turbocharged cars need load to build boost, so even with the waste gate closed it will not just build boost going through the rev range unless you are on part or full WOT.  So for example if you had a pressure sprung actuator that is closed, if you rev it on the spot it will go from 25hg to 0psi. This is due to the vacuum from the engine levelling out but does not have enough  load to build boost.

 Most of the old type pressure actuators would only hold 5-7psi before cracking with no N75 assistance. So the actuator does as it's told via the n75, and would only open when told to.

  The greatest problem with this was the waste gate would get pushed open when tuning to far with stock actuator set up,due to the spring  being to soft. Which then you need the usual upgrade 0.8 bar or 1bar to prevent this from happening. 

  If you went to far with the actuator operating pressure, this would cause problems and end up holding to much boost. A good tuner would have to map the car with waste gates forced open and slam shut when requested boost, to prevent over boost and possible other issues. 

 

Which now leads me to the new style, having a vacuum operated actuator gives you some serious control and less worry of waste gates pushing open due to the operation of hg control, having this kind of control there wouldn't be no reason for the waste gate to be open. 

  I would suggest this could be a fault from factory, if the waste gate is stuck open on tick over and normal use.

personally i have never heard of a  waste gate tick, i have only heard rattles when faulty. 

 For example look at the bmw 135i 335i 535i engines. They are twin turbo and have vacuum operated actuators on, they have a common fault with wastegate rattle. This is due to worn waste gate bushes, the waste gates are meant to be fully closed once engine has started.

 

 

As I say I have not as of yet worked on this model, so I may be way off. But once I do I will surely pass on the information I find. 


Edited by BenTTU, 06 August 2018 - 11:18 PM.


#4
T-800

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It's interesting how owners that have had the FL engine remapped are reporting no cold start rattle at all, i know that Brian told me that mapping the EA855 Daza engine has this added 'side' effect......

 

I'm also told when remapped (by MRC) the cold start 'theatre' of the FL is pretty much none existent, it also doesn't run at the high Idle on cold start just the normal 850 RPM.

 

I actually wonder how much noise is waste-gate 'rattle' and how much is engine retardation to get the cat heated up quicker in those 20 secs.

 

Although since i fitted the Active valve controller by Cete Automotive i find the cold start noise has gone.


Edited by T-800, 07 August 2018 - 07:41 AM.


#5
terminator x

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O/T but when I used to run around in Scoobies we always uprated the actuator before we got the car mapped.

TX.

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#6
RS3Dell

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O/T but when I used to run around in Scoobies we always uprated the actuator before we got the car mapped.
TX.
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John they were Scoobies not Audis.😂

In the old days thats what you did but now days its a bit more sophisticated mate.😁

Dell.

Edited by RS3Dell, 07 August 2018 - 08:45 AM.


#7
terminator x

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John there were Scoobies not Audis mate

Dell.

Ha ha true and a long time ago ;)

TX.

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#8
T-800

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Interestingly the Turbo specialist I spoke to said they do a lot of work on Mitsubishi cars as he described them as having poorer quality turbos that gave issues from new.

They do a lot of re-sleeving the pivot point where it passes through the exhaust casting.



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