Wtf Mbc?!?!

Alright well lately my ebay mbc has been wackin out or somthng. The lowest I was Ever able to set it was 12psi to be safe with my evoIII but not any lower than that. Since gas has been so high I havent dogged it for about 2 weeks until today and somehow I kept getting 14-15 psi in 3rd gear and 12-14 in 2nd. Wtf? Is it time to upgrade to a better boost controller like a electric one what? My mbc has never given higher numbers before and the screw(on the mbc) is as far as it will go out without falling out. Any ideas would be great. Thanks again!

Are you sure its not boost creep or boost spike? What kind of exhaust are you running?

My MBC is starting to act up also. Though my car's been in the shop for over a month, when I was driving it around, the boost didnt seem to go up, despite several turns. That, or the boost guage isn't doing it's job, which is much more scary!

I am currently saving up to buy a GReddy Profec B Spec II.

Reason 1= Excellent reviews on functionality, performance and ease of use, per dollar value; both here on the forums and from people at meets.

Reason 2= A comprehensive tuning guide is available, posted by BoostedSpyder, which can be found here:

http://www.automotiveforums.com/vbulletin/showthread.php?t=247106

i have a 3 inch greddy exhaust. I mean I need to be pulling lower numbers like 10-12psi on that turbo. The boost has never spiked before I dont know why it would now...but either way if I bought an electronic boost controller wouldnt it allow me to get 10-12psi either way?

Try connecting the line directly to the actuator and see how much boost is produced. Whats the EvoIII GT actuators set at anyways?

if you paid 4.99 for a ebay bc you get what you pay for. I was runnin 263 hp in my 95 gst with evo turbo and a dejon tool mbc. Never had any problems with it. My 98 gsx with a 6bolt again i used a mbc i picked up for 50 bucks. Never had a problem with it. Expensive b\c are over rated and (expensive) for people that arent going for crazy hp. Its very common to get a couple of psi spike with the evo especially if you dont have a evo 02 or ported o2. If those numbers start climbing above 16 psi that might be a problem. In 3rd gear, around 2500-3000k floor it, till about 6-6.5k. If you think its set for 12psi because thats what it reads in 1st and 2nd, i wouldnt worry if it climbs to 14 or 15. Its very common

Try connecting the line directly to the actuator and see how much boost is produced. Whats the EvoIII GT actuators set at anyways?

This is always the best thing to do to rule out a bad boost controller... My boost is a little higher now just because the weather up here is a bit colder. I know you are in texas though, not sure if the temp drops down there this soon.

I think that should be made a sticky some good info there!

my friends supra had the same type a prolem with his $2 mbc off ebay. turned out that the instide of the mbc was coroded pretty badly for some reason.

Yeah like 95 GSXRacer said the weather probably does play a key role in the turbos that everybody uses, because the air is more dense.

Just a reminder to everybody:
Make sure that your coolant level is up and that it has the correct mixture to not freeze and to cool the engine which is its purpose.
Also make sure that you have the correct oil for the winter.
And last but not least make sure if there is any water in your gas tank, make sure you get most of it out. Wouldn't want anybody's gas lines to freeze up when water runs through them.

Just trying to do my part, I heard that this winter is suppose to be a bastard so do your best to be prepared. Good Luck everybody on the roads, have fun, but play smart.