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lower boost pressure ????????

Posted: January 4th, 2004, 2:42 am
by foxhound
This might sound silly, but is there a way to lower the boost pressure on an internal wastegated turbo charger? Like from the stock boost level of 7-8 lbs to maybe 2 or 3 lbs? Thanks

Re: lower boost pressure ????????

Posted: January 4th, 2004, 10:54 am
by OsoSlo z28
not w/o ghetto-rigging it. why would you want such a low pressure anyways?

Re: lower boost pressure ????????

Posted: January 4th, 2004, 2:28 pm
by foxhound
Well, I figured I'd start off low so I wouldn't need to worry about an intercooler or that much piping or much fuel managment or too much stress on my sohc. At least not until I get my funds up again. So how do I go about this "ghetto-rigging"? Also how was racingmazda.com able to set it at 4psi? Was it because of the external wastegate?

Re: lower boost pressure ????????

Posted: January 4th, 2004, 2:42 pm
by mrspanky79
aftermarket boost controler, set it to what ever you want

Re: lower boost pressure ????????

Posted: January 4th, 2004, 5:55 pm
by ryanlindenberg
i think you can just replace the spring on the wastegate. put one on with less tension. if you go with the aftermarket boost controller method, you will have to get an electronic one.

Re: lower boost pressure ????????

Posted: January 4th, 2004, 7:23 pm
by mrspanky79
"have to get an electronic one" why?
all they do is go between the turbo and the waste gate and you set the boost to what you want. when the controller sees the boost you want it opens the waste gate. very easy to install all you have to do is hook up 2 vaccum lines and mount the controller some where. The only electric part is if you have a dual stage boost controller and all you doing is hooking up a switch so if you want to see a second boost leave it switches to a second controller.

Re: lower boost pressure ????????

Posted: January 4th, 2004, 9:42 pm
by foxhound
I though a boost controler could only increase boost pressure from the stock setting. A controller is only a controlled leak to fool the turbo. If it isn't leaking then it's like not having a boost controller at all. Isn't it??????

Re: lower boost pressure ????????

Posted: January 4th, 2004, 11:00 pm
by OsoSlo z28
foxhound, you are 100% correct. as for most of the other replies, ignore them. all a boost controller does, regardless if it's electronic or manual, is allow greater boost OVER THE STOCK SETTING. the only reply above that is close is to replace the stock spring with one that has less tension. you're problem will now be finding a spring of right size and tension that will fit what you need. now, if you have an aftermarket ext wastegate, it wouldn't be so hard as they have many diff spring rates for desired boost applications.

my advice to you, though you may not like it, is to wait. wait until you have everything you need to do this setup properly. you'll be much happier in the end. doing things half-a$$ will only get you half-a$$ results.

Re: lower boost pressure ????????

Posted: January 4th, 2004, 11:16 pm
by VizualXTC
LOL, I love these topics.

But Foxhound, seriously, don't listen to Ashley (OsoSlo z28) he sold his MX-3 and bought a V8 :looks down in shame:

But kidding, Ash knows his ****. If it were ME tho, I would find an external wastegate and block the internal. That or find another turbo with an internal with the 2-3# boost you want. What turbo do you currently have that has the 8# setting? From what I hear the sohc can handle 8# with ease, but it's all what you're personally comfortable with.

P.S.
DOWN WITH V8'S!!!!!!!!!!!

Re: lower boost pressure ????????

Posted: January 4th, 2004, 11:18 pm
by foxhound
I guess I will wait until I get more cash flow. Thanks for the fast replies Ash.

Re: lower boost pressure ????????

Posted: January 4th, 2004, 11:21 pm
by OsoSlo z28
leave it to the potato boy to talk smack on a car that's faster than his :D

***this just in, thread officially hijacked*** <img src="http://www.jaxstreetscene.com/forums/ht ... jacked.gif" alt=" - " />

<small>[ January 04, 2004, 10:37 PM: Message edited by: OsoSlo z28 ]</small>

Re: lower boost pressure ????????

Posted: January 5th, 2004, 12:14 am
by ltjrunner
down with v-8's.......hahahahahahahaha

Re: lower boost pressure ????????

Posted: January 5th, 2004, 1:21 pm
by mrspanky79
so your telling me that when i built my turbo set up and put a turbo xs dual stage boost controller on and work my way up from 2 psi i was dreaming because i know the stock turbo on a eclips puts out more then the 2 psi on the stock set up. :confused2: well that was a long dream that felt so real since i took my time to go up to 5 psi and played with 8 ones. Oh well i will go back to dreaming in the spring.

Re: lower boost pressure ????????

Posted: January 5th, 2004, 1:23 pm
by mrspanky79
oh ya i guess the instuction i have in my desk for the xs has a miss print in them :shrug:

Re: lower boost pressure ????????

Posted: January 6th, 2004, 10:51 pm
by OsoSlo z28
i can't tell if that's sarcasm or ignorance. lets review how a wastegate works mmkay?

the spring needs a boost reference in order to open at the set psi level. a boost controller bleeds off a certain amount of air so when the wastegate actuator sees 7psi, it's atually higher depending on what you set it at. setting the psi level on the boost controller lower than the spring setting will do nothing. you will still get stock boost levels. this is the same idea if you were to disconnect the boost reference to the wastegate. it never gets a signal so it NEVER opens. the ONLY way to get lower than the stock setting is to replace the spring. boost controllers have no direct affect on the wastegate actuator, so there's no way they can offer you lower boost than the preset limit. take it for what it's worth. :shrug: