I just installed a Hallman Pro MBC and it's holding @ 21psi... and slightly tapering to 20psi at redline... is this safe to run on 93 Octane Shell gas?

 

Should be , stock is 19psi, and most piggy back ECU's you buy raise the boost to that level , you should be fine.

 

I sure as heck hope so. I've been there for four months. I've hit fuel cut when the weather changes cooler two times. Anyone know if this is safe?

 

i have the hallman MBC and at first i was peaking at 22psi, but i lowered it to 20psi max. So far so good, i havent gotten any fuel cuts and im running on 93oct pump gas and the car is stock except for a greddy type s with the single spring mod. Now i smelled a little fuel when i was boosting 22 psi, i think it was because the car needed more fuel at the boost level. I got a question for those who own the hallman. When i first installed it, my boost wouldnt go past 11psi, and the knob was all the way to the left which is supposed to be "stock" boost. isnt it supposed to be reading stock boost when the knobb is turned all the way to the left? well w/e i was peaking at 11psi so i was like WTF??? after a few turns my bost when from 11 to 22psi and it pulled like a bat outta hell all the way through redline. Did i fix my problem? why was i boosting no more than 11psi with the knob all the way to the left which is supposed to be stock boost not less than stock?? any feedback is appreciated in advance.

Backt o the topic, im peaking at 20psi, and it feels good, no problems, solid boost, hallman rules.

 

It should be safe, if you have te hallman MBC then it shouldnt be affected by the weather according to them since the design of the BC is different. But if you hit fuel cut, disconnect the negative battery cable and reinstall it after 5 mins and let the car idle for another 5-10 mins. Then again, weather shouldnt affect this MBC. Im running on 93oct chevron gas and it constantly stays at 20.

 

Now what about if you have the walbro upgraded fuel pump, can you run say 23-25psi? Or would that just be beyond what the turbo can run efficently? Or run the car too lean? Just wondered.

 

I believe that stock actually is 10-11 psi. Once you put on an mbc if you have it set all they way to the left (essentially holding no boost with the mbc) then I think the boost level is controled by the wastegate or something on the turbo? Someone with a little more knowledge feel free to chime in, i'm just pretty sure I remember that info from somewhere else on the boards.

 

The wastegate itself will hold around 11-14 psi with no boost controller. Running around 20-21 SHOULD be ok but you never know. Each car is different. I would stick with 19.. that is known to be ok. The Walbro will not make you able to run more boost unless you are maxxing out your pump (Which your not). The pump only pumps so much, the ECU tells the injectors to spray x amount (Which is MUCH less than your pump is pumping). The Pump will ONLY help if your stock pump is failing or can't pump enough to keep the fuel pressure where it should be.

 

30 psi is fine w/ the wright fuel !

 

lol, fast foward must be using HIGH octane 94

 

i've hit as far as 1.51 bar thats about 21.9 psi stock. all i have is intake, but i run about 93 octane fuel. not constant but thats my highest spikes of boost, usually at 3/4 throttle.

 

117 octane w/ big blower

 

Depending on the tuning, you may not need 21 psi. I dynoed my car at Quantum Racing two weeks ago, and the car put down more peak horsepower with 20.5psi than 21.5psi. My mods include 3-in catless turboback, intake, and dynoflash.

 

..Which is what I try to tell everyone. More boost does not always mean more power; particularly on stock turbo and ECU, etc. There are ways to make more with more boost on stock turbo but not with that particular car.

Mark