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Discussion Starter #1
i have the following mods and no tune on my sst.
uip, hks panel filter, resonated test pipe, cbe, and a mbc
when i hit 3k rpm im already at 15psi i spike to 23 by the time im at 5k then it tapers down to about 18-19. my mbc is made by turbo smart. the mbc is connected to a tee that also contains a ball and spring. i was using the tee with no ball and spring before becuase i feared the 23 psi spike. after i installed the test pipe i put the ball and spring back into the tee and thats when i noticed this early surge of boost. the car runs much better and is a lot faster now.
Is there such a thing as too much boost at low rpms? can this cause knock?
Thanks,
 

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Sounds to me that you're boosting just like a stock MR maybe a PSI above at 23. Nothing to worry about just from those numbers - from what you're telling us. However - it's what you're not telling us that may be cause for concern.

Yes, more pressure leads to detonation. And the most likely RPM range for detonation is the torque peak, where the load (pressure) is the highest. And detonation is bad - all of it (unless you're in the business of taking down old buildings).

As others have stated, get a proper tune.
 

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are you a bot?
 

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The numbers don't seem bad, however some people will tell you to avoid anything but ECU boost control with the SST. I'm pretty sure stock top boost for the MR is closer to 21 psi, but 23 isn't out of the question. The taper seems normal. It's sort of possible to have "too much" boost at low RPM, but it depends what gear you're in. It may not be a great idea, for reliability sake, to have high boost in low gears. Stock MRs are limited in low gear (somewhat severely). 2008 models are limited by throttle and later models are limited by boost. My '08 was scary pulling into traffic before I got that changed because they were limited so much.

But as said above, your best bet is to find someone who knows how to tune the MR and consult with them.
 

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You have fairly low boost at 3k, really late spool-up, kinda weak peak boost, and a really bad boost management system (MBC). Change all of the above.
For example: 22 psi at 3k, 25 at 3.5k, holding until 5.8k, then slowing dropping to 20 by 7.5k. 3-port solenoid using the ECU to control/error correct/etc.
 
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