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14 psi wastegate spring, is it safe?

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#1
Both in Reddit and here, I've caught notice that people recently suggest to use a 14 psi wastegate spring. I recall 3 years ago that using this was sheer turbo suicide. What exactly has changed for people to recommend this? Did the tuning strategies change and we found a ceiling limit so that it does not allow it to destroy our stock frame turbos?! I'm clearly intrigued by this. I have two wastegates sitting on my house and will jump on the chance to buy a 3 psi spring to add into my wastegate.

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OP
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Thread Starter #2
I messaged a couple tuners, still can't find any information on the subject.

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OP
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Thread Starter #4
The 11psi spring is sufficient at the moment, no issues with boost dumping. I was always under the impression that the 14 psi spring would cause the stock kp39 turbo to overspin?

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#5
I have the MRX turbo with the Mountune 17 lb billet wastegate actuator. The reason we started running these over their initial offering is the wastegate wasn’t staying shut through the entire powerband and power was being squandered.
 


OP
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Thread Starter #8
Stock kp39 currently, x37 turbo is being installed by me in about a week. My stock turbo has the 11psi TS WG at the moment.

I'm interested in installing a 3psi spring into the wastegate, but would the x37 even benefit from it. I figure it would just make a whole lot more heat.

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#9
I would ask a tuner who’s had experience with them to see what it needs. Its on quite a few cars in here and there is an X37 thread.
 


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Bedford
#10
Does the higher rated spring not cause over-boost, in the UK on the standard Turbo they do not use anything more than a 7 PSI spring as the stock is only 4.5 PSI what tune are you running?
 


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#12
should actually make the boost more stable
Please give a little more insight, as I have always been led to believe that that a spring of 11/14 PSI on the standard Turbo and even on some Hybrids would cause potential issues unless it has been properly mapped in.
 


MagnetiseST

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#13
I running a Tune+ IWG (no one knows the exact pressure on this besides Adam at Tune+) its somewhere between 11 & 14. Seems to work just fine on my stock turbo, boost happens and then it stays instead of falling off at 5k rpm
 


OP
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Thread Starter #14
I have the tune+ WG from turbosmart, to my knowledge it's basically a 11psi spring. My boost regardless is tapering downwards after about 4900rpm. Everyone always stated that they have boost past 5k, I have a hard time believing that though.

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MagnetiseST

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#16
I have the tune+ WG from turbosmart, to my knowledge it's basically a 11psi spring. My boost regardless is tapering downwards after about 4900rpm. Everyone always stated that they have boost past 5k, I have a hard time believing that though.

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Its closer to 11.5~12. I hold 22psi to 6k in 4th.
 


OP
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Thread Starter #17
22psi at 6k ? Interesting, by any chance would you happen to have a datalog?

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MagnetiseST

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#18
22psi at 6k ? Interesting, by any chance would you happen to have a datalog?

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I do, but I'm looking at it now and its not even that high. Maybe the AP is displaying something slightly off. At the end of my log (6krpm) Its at 17.03psi.
 


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#19
Stock kp39 currently, x37 turbo is being installed by me in about a week. My stock turbo has the 11psi TS WG at the moment.

I'm interested in installing a 3psi spring into the wastegate, but would the x37 even benefit from it. I figure it would just make a whole lot more heat.

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Has the x37 been fitted, or are you still running the standard Turbo
 


OP
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Thread Starter #20
I've noticed many times that people report holding boost high in the revs, but only on the AP. When they go to look at datalog it's a different story! I noticed it myself on many occasions when datalogging. The AP is only INFERRED results not ACTUAL. My boost tapers down to almost 19psi at 5800rpm, at 6800rpm I'm barely making 18psi. This is all with the tune+ wastegate.

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