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Old 07-23-2006, 01:50 AM   #1
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i know if probably bee n talked about a lot, but i cant find any on da miata. im getting boost creep of an extra 3psi. i am running like 10 psi at redline. but at 3800-4600 its about 14-15psi and da 1.8 inj lock. and from 4600-5800 itsa bout 12psi. so my question is, is it da downpipe.or maybe da turbo. ive read that some port the turbos wastegate thing. i just want to knwo if changing da downpipe to a 2.5" will cause less boost creep or none at all. the boost controller im using is just a coil spring holding the wastegate rod. thanks
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Old 07-23-2006, 01:56 AM   #2
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Is your boost contoller connected between the port on the turbo and the Actuator rod or at the BOV and the intake manifold?

and plz i know know its not a grammar forum and im not the spelling police but Da is waaay 90's.
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Old 07-23-2006, 01:56 AM   #3
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on da miata use da mbc, manual boosy controller
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Old 07-23-2006, 12:35 PM   #4
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well its between the wastegate rod.
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Old 07-23-2006, 12:39 PM   #5
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i forgot to say that i have a john b manual boost controller but i didnt like it.
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Old 07-23-2006, 02:00 PM   #6
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Using a helper spring for boost control can be very effective, BUT it can cause boost creep b/c it limits the opening range of your wastegate. Sometimes on short-arm wastegates, shortening the wastegate arm too much can do the same thing.

Considering that you have only a helper spring holding the wastegate closed, when the wastegate is supposed to open, the strong spring is holding the wastegate only partially open instead of fully open, hence the boost creep. You might want to just try using another MBC (aka not ****'s since you didnt like it) instead of a spring. I've never tried it, but have read good things about the Hallman MBC. YMMV.
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Old 07-23-2006, 02:50 PM   #7
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ok!
i saw many hallman boost controllers.
what type should i buy? i dont want to spend a lot of money either on a boost controller!
thanks
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Old 07-23-2006, 03:20 PM   #8
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FM sells a very high quality mechanical boost controller on their site for $47 - relatively cheap for something that you know will work right. I think anything on the cheaper side is a bit of a risk, but many have had good results from the ones **** used to sell etc.
-Ryan
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Old 07-23-2006, 07:53 PM   #9
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I think it was the Hallman ProRX. Do a search here, and I'm sure you'll find it. I know that WhiteRoadster raved about it as well as a few other members. I think it is also popular in the DSM world. As for FM's MBC....it looks exactly like my **** MBC so I don't know how "quality" it is in comparison. YMMV.
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Old 07-23-2006, 08:13 PM   #10
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my vodoo mbc from ebay works fine for me only like 10 bucks to for that price i figured why not.
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Old 07-23-2006, 08:13 PM
 
 
 
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