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Is everything normal with my SMBC?

858 views 10 replies 5 participants last post by  Xedus129 
#1 ·
I got my SMBC from SPATL yesterday and installed it. Noticed an instant difference, off the line the car felt way more agressive and seemed like it was pulling harder. Car felt awesome.

I know the stock boost gauge isn't good to base things off of... but all day yesterday, 2nd gear and up the stock boost gauge was going about a quarter to half-way into the red every time. Today driving the car around, the stock boost gauge in the same gears would just barely get into the red.

Did my ecu pick up on the smbc and adjust for it... dumbing the performance down a bit or something like that?

Also, yesterday I could pretty much turn it up so that only 1-2 threads were showing and not go into limp mode or get fuel-cut or anything. Today it seems like unless I leave 4 threads or so showing, I go into limp mode within a few minutes. Any ideas about any of this?
 
#2 ·
The ecu will adjust somewhat and try to reduce timing and adjust fuelling, but since your using a mbc, the boost is set by what you set the mbc at.

That being said, weather has a big effect on how much boost you run from day to day. If its early morning and the air is cold and dense, you will make more boost. If its the middle of the day and its hotter and the air is less dense, you will make less boost. Temp. is by far the biggest factor in how much boost you run and it directly effects density altitude, which is the air density.

Heat soak is another factor that comes into play. The more boost you run, the faster the ic gets heat soaked and this directly effects the air density going into your motor. There are a lot of factors that make the boost vary a little bit from day to day and that is what the anticipator is designed to do, allow you to run close to max boost without over-boosting and hitting fuel cut on those cold mornings or those cold winter days;)

John
 
#3 · (Edited)
Did you install it all correctly and zip tie the hose on the bottom? Because I boost into the red 1/2 way + some and never hit LHM CEL or Fuel Cut.. I have 2 threads showing from the top. I only go that deep into the red in 3rd gear and higher, first gear gets a sliver into the red and then 2nd is about in between. Also when I installed it, it was warm out, then it got cold a day or two later at night, as I was boosting in 2nd at about 4000RPMs the guage flew up all the way into the red and then the car kind of bucked and the boost stuck down at normal 2nd gear boost. After a restart I haven't had the same problem again. What kind of fuel are you using also, because T7 adjusts factors based on some electrical charge test of the fuel (Read it on wiki). I'm using NY 93 Octane (and it shows as my wallet is empty ;oops: ). But if the hose is loose it could be messing around, and also with weather changes.
*edit* Also, If yours is auto it could be a little more conservative with boost pressure.
 
#4 ·
Xedus129 said:
Did you install it all correctly and zip tie the hose on the bottom? Because I boost into the red 1/2 way + some and never hit LHM CEL or Fuel Cut.. I have 2 threads showing from the top. I only go that deep into the red in 3rd gear and higher, first gear gets a sliver into the red and then 2nd is about in between. Also when I installed it, it was warm out, then it got cold a day or two later at night, as I was boosting in 2nd at about 4000RPMs the guage flew up all the way into the red and then the car kind of bucked and the boost stuck down at normal 2nd gear boost. After a restart I haven't had the same problem again. What kind of fuel are you using also, because T7 adjusts factors based on some electrical charge test of the fuel (Read it on wiki). I'm using NY 93 Octane (and it shows as my wallet is empty ;oops: ). But if the hose is loose it could be messing around, and also with weather changes.
*edit* Also, If yours is auto it could be a little more conservative with boost pressure.
How were you able to turn the SMBC up? Mine would not twist by hand no matter how hard I tried, and once I installed it I couldn't get two wrenches in there to twist it. Also, I want to make sure I'm twisting the right part. It's the big threads in the middle of the long side, correct? not the small threads on the head of it.
 
#6 ·
Xedus129 said:
The top part locks it, so losen up the top part and then use the bottom part to adjust boost then lock it.. don't tighten it too tight cuz its a pain to unscrew :evil:.
oh wow I would have never figured that out, so I unscrew the knurled ring on the top then turn the middle threads? Sorry for the stupid questions, I don't feel like running out to the parking lot to check right at the moment. :cheesy:
 
#8 ·
Wassobe said:
I know the stock boost gauge isn't good to base things off of... but all day yesterday, 2nd gear and up the stock boost gauge was going about a quarter to half-way into the red every time. Today driving the car around, the stock boost gauge in the same gears would just barely get into the red.

Did my ecu pick up on the smbc and adjust for it... dumbing the performance down a bit or something like that?
Yep. The SMBC was set too high. The T7 picked up on the change and is moderating your boost at the thottleplate. The LHM solenoidn on the motorized throghttlebody will closed the throttleplate if the ecu sees too much pressure. Temperatures play an important role as to how much boost gets sent. On colder days, boost is a bit higher and car feels stronger. But with the SMBC on a T7, the setting needs to be mild. Try to enjoy the better turbo response with out sending the boost into the red on the stock boost gauge or this will happen. The Fickle T7 can moderate boost either at the BPC or the Throttleplate. Lower your setting on the SMBC. You might even unhook your battery for a few minutes to get things reset and then give it a run. Keep your setting mild.
 
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