Forge mbc

[SharkDiver]

Hey all,Well I got my forge mbc and my fcd installed.Hears the thing,I cannot get the mbc to stay at 17-18psi.I double checked all my connections and all my vac lines are zip tied.What it does is it will spike to 21-22psi then drop to 15psi at about 4k rpm then it will go back up to about 19 or so no matter what setting I have it at.If I turn the boost up higher it will spike past 22+psi and still drop back to 15 or so then shoot back up.I tried both springs in the MBC and had the dial all the way down (-) and all the way up (+) and it dont stop the spiking.I cant find any info on this mbc anywhere on the net,All I can find is that people say they are using it and are not really having any problems.Forge dont have a user forum to go look at and Ive emailed them but they cant tell me anything because they dont know anything about the speed3 they say.He just said to try both springs and different settings to see if it will work the way I want it to but it dont.I dont know what to do,Im thinking that this mbc just spikes and I will not be able to tune it right because it will not hold psi.
Any ideas before I give up and sell this thing and try another brand?I was told forge makes great stuff so I was not expecting to have a problems with spiking or whatever the problem is Im having.

Shark

 

[tru-boost]

there are at least 2 others using this MBC with no complaints, i'm not sure what it could be . it sounds like the throttle control is playing with you.

 

[SharkDiver]

there are at least 2 others using this MBC with no complaints, i'm not sure what it could be . it sounds like the throttle control is playing with you.

Do you know who the other people are?I would like to ask them a few guestions.Ive been searching the net for anything about the forge unos but nothing that is helping me.It would be much better to talk to someone that has the same car as me.Right now I switched back to the softer spring and got the nob turned all the way down (-).It didnt seem to jump around as much today on my way to work,Im wondering if the ems will help with that as I drive it a bit more.

 

[tru-boost]

driver311 .......... that is one of the users names (the guy who runs 12.7's)
i know there is at least one other, but i cant find it at the moment.

 

[SharkDiver]

driver311 .......... that is one of the users names (the guy who runs 12.7's)
i know there is at least one other, but i cant find it at the moment.

Thanks..By the way I have it all hooked up according to the how-to thread by Laloosh incase some people are wondering how I have it hooked up.

 

[driver311]

that is the right way. I hooked mine up that way and I spike 21psi and holds at 18psi until 5800. I base this off running though the gears. If I punch it in 5th down low it spikes high and holds for a bit. I run the forge with the soft spring. I have it turned pretty much all the way down. Maybe you have a boost leak?

 

[laloosh]

what do you with the soft spring? Their mbc has interchangeable springs? Also what the deal with your tranny, i heard u screwed it up

 

[laloosh]

also as i siad, the turbosmart does not spike one bit. i will actually go take a video for you tonight lol. ill be back in 30 min

 

[laloosh]

here you go buddy, a pull through the gears. 40-130 as you can see i get very little spiking. AS for the lil dip in 4th gear, who knows, thats probably the ecu trying to do its thing and fcd say no lol.

Best i could while driving and video taping....hope it helps.

http://www.youtube.com/watch?v=naBM-NY9z8U

 

[Haltech]

here you go buddy, a pull through the gears. 40-130 as you can see i get very little spiking. AS for the lil dip in 4th gear, who knows, thats probably the ecu trying to do its thing and fcd say no lol.

Best i could while driving and video taping....hope it helps.

http://www.youtube.com/watch?v=naBM-NY9z8U

(yippy) LOL that was great!

 

[SharkDiver]

Thanks for the replys.The video was nice to see.It looks like you also go to about 20psi then drops down to 18 and holds.The Forge unos comes with 2 springs and you dont get any info on them at all.All it says is you may want to switch springs if you are not getting the psi you want.Someone on the net somewhere said they think the soft spring is good for 1-23psi and the heavy spring is for 24psi and up.Thats all the info I can find on teh springs.
Thanks also Driver311 for the info.I think I will leave my mbc on for another few days to try and dial it in or see if the mbc leaks before I take it back apart and go stock.
GUESTION=If I have the nob turned all the way down on most any mbc shouldnt my psi be somewhere in the low single digits?What if I only want to run 7psi,Will the ecu let that happen?I have mine turned all the way down and it still goes to +15psi with the soft spring.Is that normal or could the mbc have a leak in it.I dont see any bad vac lines and everything is zip tied so I dont think I have a vac leak in my hoses.I really wish I knew someone close by that had a mbc I could switch out with and see if I have the same problems.Im really starting to think the MBC is faulty somehow but I dont know how to check and see besides hooking it up and using it.

Shark

 

[laloosh]

you cant go lower than stock with a mbc. my turbosmart on the lowest setting possible reads what i read before i even installed it.
As for why you cannot hold more then 15psi, who knows, what intake do you have on there? you also said you turned up the boost controller all the to the positive side and it still held only 15 after a big spike. If i did that with my turbosmart i would need a big net to catch my rods as they return from orbit lol. i dunno what to tell you, but it sounds like boost controller is either hooked up wrong or a defective unit.

 

[laloosh]

also keep in mind that you might be detecting knock/pulling timing or flat out leaning out. if the car spikes to 23 or whatever than fall to 15 only to go back up as the rpm rises you might be knocking/leaning at that certain point, hence the reason for the big drop and the throttle closing on you. Try this, put in the soft spring in and turn it all the way to the negative side. Go do a pull in 3rd at 40 till 100 in 5th. Record what happens, im willing to be it wont shoot down and back up. now turn the boost up little by little and repeat the follow to see if it goes to 15 then back to 19. Some tells me you have this thing set up way tooo high lol

As for the obvious things you should know;
run the highest gas you can meaning 93 or higher
run an intake that doesnt lean you out. meaning cobb or cpe or the stock box.

 

[SharkDiver]

To be honest,Right now I dont have time to mess with this even tho I just said in my other post I was going to keep it in.Im very busy for the next 3 or 4 days with family stuff.Im thinking I want to just put it back to stock untill I have a day to mess with it.What I was thinking was just put the vac line back on the solenoid and wastgate to connect the two and either take the ball out of the mbc or just turn it all the way up instead of removing it.Would that be a problem you think.I know I could just put a connection thing in there and just put the 2 hoses together and bypass the mbc but I was wondering if this idea is bad or not removing the ball or turning all the way up.Also leaning out may be a problem since I have a cai.

Shark

 

[tru-boost]

nice vid laloosh !! i love the sound of a FORGE valve at 100+ !!

 

[laloosh]

lol i try my best(hi)