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512RWHP... 503RWTQ... 7M
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Discussion Starter #1
So after getting the car set up and upping the boost and all that stuff, and after finally getting her home and giving myself some time to drive her around and get used to her, I've decided it is imperative that I get a bigger w/g spring...

The thing with this 6-7psi spring is that yes it CAN reach 14 psi, but shit man, you gotta get her near redline before she sees that... So tell me, if I had a 14 pound spring in there, I should hit 14psi alot sooner, right? Plus, then I can get lots more boost...

I just gotta find a retailer and get this handled... :) :)
 
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no.. 14 lb spring means the minimum amount of boost you can run is 14psi and you can use a controller to turn it up, but no lower.. 6-7psi spring with controller won't hit 14 psi any later than a wastegate with a 14psi spring.. this is just my thought, I could be wrong?
 

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512RWHP... 503RWTQ... 7M
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3,292 Posts
Discussion Starter #3
I was thinking maybe a 14psi spring would help get the psi up faster because the spring isnt fighting the vacuum or whatever of the boost controller... Im not going to try to sound like I know what Im talking about here, so I'll leave this up to the experts, lol... :lol: All I know is having a built ass motor sitting on a monster turbo with a pos 6psi spring is whack! :D
 

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Yea, I've got a 9psi spring and it starts to open the WG by 5psi so by the time you hit 9psi you have lost a bunch of spool in the lower-mid band. No matter how I set the gain on the Profec B spec II it still opens by 5psi. I too am thinking about getting a 12psi spring.
 

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I had a 7psi spring on my T04 kit that I had and ran 18psi all the time. I even turned it up past 20 a few times too and had no problems getting there. If you have a GOOD electronic boost controller and hook it up the right way, you can actually force it closed with the pressure until the boost controller decides to slap it open. Hence, the two ports on the wastegate. That's how I always made mine work. I never needed a bigger spring.
 

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i got a 1bar spring... it still kinda spools slow, but it boosts hard. i havent tried messing with my mbc.
 

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512RWHP... 503RWTQ... 7M
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Discussion Starter #7
Well, Trent, I have a good ebc... HKS EVC IV... :dunno:
 

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when this baby hits 88mph
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for the most part, a 14psi spring is going to hit 14psi quicker than a smaller spring w/ a boost controller.
the reason being is how a boost controller works. it will bleed off the vac signal to the gate/actuator to increase boost past the preset amount. when using an electronic controller you can set the "gain" on the speed it does this. if you have the gain set really high, there will be little difference b/w a 14psi spring and a 7psi spring and ebc. however having the gain up high will tend to overshoot the boost and cause issues like boost creep or spiking. this can also be caused if you have a too big of a spring in the gate as well. in my 38mm gate i wouldnt want to run a spring any stiffer than 14psi, while in my friends 60mm gate he is running a 26psi spring.
so in the end, all things being equal, the larger spring will hit the boost sooner than a small spring w/ a boost controller. how much the difference is will depend on the gain/response tuning on it.

hope this makes some sense
 

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512RWHP... 503RWTQ... 7M
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Discussion Starter #9
Thanks DB, that was easy to read and understand... My w/g is 42mm, so I think a 14psi spring would be a good size, well actually I think they just come in bars, so like a 1.1 or 1.2 bar spring which would be a bit higher than 14psi...

Now I just gotta figure out where to get one... :p
 
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