Hey guys..

I am currently having some goofy issues with my boost spiking way high when its under load..

Here is the situations:

Situation 1) boost is perfectly normal if i am at for instance the race track..(if i start out in first and red line it and take it through all the other gears, it will be perfectly normal hitting a high of about 22 or so and holding fairly well...


Situation 2) I am cruising at a fresh 45 mph in 4th gear or even 3rd and at about 2 grand or 3 grand and i have to pass someone.. The boost immediately spikes up to and sometimes beyond my 30PSI gauge.

I had a buddy do a log for me and it seems that i have a peak load of about 344 at around 4600RPMs.. (im told that is very high) but i only have about 2 counts of knock until like 7 grand where it goes to about 7... (BTW the boost drops to almost 20 PSI within about 2 seconds MAX)

If anyone is interested in seeing the log, i can send it to you, it is in the Microsoft Excel format...
(just tell me your email)


Conclusions:

Slowboy Racing MBC not reacting fast enough, or just gone bad?
Stock EVO IX wastegate acting up (but its holding boost at certian times)




The funny thing is though, i was previously tuned by AL on that exact same setup.. so i dont know why all of a suddon it is doing this..

I asked AL what was going on and even asked if he would look at a log i had (since he tuned my car) and i have yet to hear a respond yet..


Thanks alot in advance..

 

Change the boost controller its ****ed

 

bump for any last opinions before i put a new MBC in...


thanks

 

This is not Advanced. This is very normal - your boost is set WAYYYYYYYYY too high. You're only seeing 22-ish when rapping through the gears, because of the fact that you're never below 5500rpm, so you only see the tapered boost. When rolling into boost at low rpm, you're hitting peak boost, which obviously spike much higher than where the boost tapers to at 5500 and above. This is very very basic and normal. Every Evo (on stock turbo) hits peak boost early and tapers down, so you never see as high of a boost reading if you're rapping through the gears.

I don't know why you'd get that particular MBC when there are proven, awesome MBCs on the market, so maybe it is acting up some, but the crux of your "problem" is just not having a basic newbie understanding of how our boost works.

 

Thanks buddy but the problem was solved with a simple switch of the MBC.. slapped in my buddies turbo XS and it held perfectly fine.

As for the Turned WAY TO HIGH issues, that was not an issue because when i had it turned down to like 16 pounds and it was still doing the same thing.

This could have been advanced if that were not the issue. And i do understand boost just wanted opinions before i started ripping crap apart like the wastegate or anything on the lines of boost related items.


Mods you can close this out if you choose to.