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Is there any way to have an MBC intalled in parallel with the N75 and boost not taper down???

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Old 01-11-2005, 07:01 PM
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Default Is there any way to have an MBC intalled in parallel with the N75 and boost not taper down???

I read lots of posts about the MBC setups in the archives and people said having the MBC only caused some drivability issues at high speeds as boost builds up too quickly due to lots of exhaust gas available, so I still want my N75 to control over boost yet would love to have higer boost near the redline since I have K04's and an adjustable FPR set at 5 bar in my car. I haven't got my car back yet but I'm already thinking about what I will do after I get the new clutch broken in. Will adjusting the N75 work with no problem? Just thinking out loud...if there's no solution, then I may just go AWE stage 3. Any input will be greatly appreciated!
Old 01-11-2005, 07:06 PM
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Default No. If the MBC is installed in parallel, then whichever device has a lower setpoint...

(MBC or N75) will prevail and set the boost to that level. If you are running K03 software with an MBC in parallel, then the MBC will just cap the maximum boost. It won't prevent the boost taper from the K03 software.

-Dave Pramanik
Old 01-11-2005, 07:08 PM
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Default Not entirely true really.

If you run MBC in parallel on K03 software with bigger than k03 turbos, the boost won't taper as much as it would with k03s. This may cause you to have a flat boost curve, capped at the MBC's setting all the way to redline, depending on your mods and MBC setting.
Old 01-11-2005, 07:13 PM
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Default Really? Are you just speculating or have you seen it?

So if I set my MBC at 17 lbs, will I be able to sustain 17 lbs all the way to redline?
Old 01-11-2005, 07:18 PM
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Default Yes, turn SEL scaling up. My car hits 1.25 bar and stays there to redline

If I turn SEL scaling back down to 90% though, the boost will ramp up to 1.25, then taper off.
Old 01-11-2005, 07:20 PM
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Default Yes, people have seen it. Chaka on the forum is one example.

It depends on a lot of things. All I am saying is that it is possible. You'll have to see and find out.
Old 01-11-2005, 07:21 PM
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You can't go beyond 100% and not everyone has K16/RS6 turbos ;-)
Old 01-11-2005, 07:44 PM
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Default which MBC's are you talking about? Are they all built the same?......

I was looking at the one Autospeed sellsbut havent hears any opinions on it.<ul><li><a href="http://www.autospeedperformance.com/tsmart/mbc.htm">http://www.autospeedperformance.com/tsmart/mbc.htm</a</li></ul>
Old 01-11-2005, 07:46 PM
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Default I don't see much taper at all ... I see an initial spike of around 20 psi, then 19.5 PSI or so

pretty much to redline, controlled by my MBC setting. I will run some more tests just to make sure, but if it was tappering alot I would have noticed it weeks ago.
Old 01-11-2005, 07:47 PM
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Touche...


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