Boost gauge jumped to 10 psi, but log only shows max of 129kpa (3.7psi)? added MBC

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03-16-2009, 11:06 AM

scottv

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Boost gauge jumped to 10 psi, but log only shows max of 129kpa (3.7psi)? added MBC

I added the NXS manual boost controller this weekend and set it to what I believe to be around 4/5psi based on me blowing into it...so I'm driving with it and get on a hill in second to test where it is for adjustment and it jumps to 10 and sortof "dies out"...like hit a rev limiter or something. I looked at my logs afterwards and the top reading is about 3.7 at 4330 rpm, spark angle dropped from 37 to around 19 at this event. My boost gauge is tied into the same line coming from the front of my manifold as the MS map sensor. I'm confused. Any ideas? Also, anyone know why my boost is not coming on until a high rpm? Thanks.

Last edited by scottv; 03-16-2009 at 11:24 AM.

03-16-2009, 11:39 AM

crashnscar

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Maybe overboost protection? What do you have yours set at on the MS?

Oh, and doubt you can blow 4/5psi... even if you are good at blowing.

03-16-2009, 12:09 PM

scottv

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Over Boost is set to 152kpa, before adding the MBC I hit max of 143kpa without it cutting out like that...and I'm using the same msq settings-just added the MBC

03-16-2009, 05:37 PM

Savington

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Post your log.

03-16-2009, 06:10 PM

scottv

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Log attached below, as well as msq...this event occurred around 366.632s in the log. THANKS!

my bad, both now below.

Attached Files

datalog200903160909.xls (1.78 MB, 79 views)

ve analyzer msq recommendation after Run 2.msq (35.3 KB, 81 views)

Last edited by scottv; 03-16-2009 at 06:36 PM.

03-16-2009, 06:30 PM

Savington

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This forum allows you to post .msq and .xls files. Post them.

03-16-2009, 07:14 PM

richyvrlimited

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Kpa dropping off like a cliff with your foot to the floor? Boost leak?!

03-16-2009, 07:55 PM

scottv

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just happened to me two more times on the way home from work...yeah, foot to the floor getting up on it then it just falls on it's face. well, if it is a boost leak how can my boost gauge register that much more than my map sensor if the signal is coming from the same place? i will probably test the boost gauge and see if I have a boost leak somewhere...I will say that I'm not sure my wastegate is opening all the way-it might be hitting the inside of the downpipe because the arm on the outside doesn't go totally perpendicular to the exhaust flange so maybe flow is being restricted? I'm also on the stock exhaust still with orig cat so maybe there is a restriction and that does something to the boost? I don't know.