I just installed a hallman pro mbc. Not the RX. I turned it 3 turns out and im reading about 14-15 psi at full throttle. My 03 evo has HKS rs intake and a TBE with high flow cat. Not tuned yet. When i try to go full throtltle in the lower gears, the car bogs and jerks big time. In the higher gears like 4-5 it wont do it, maybe just one little boom out of the exhaust. What can this be? Is it too lean? Will a wallbro fuelpump and a flash dynotune solve this?

 

I doubt it, sounds like different issue. I ran my mbc at 21 psi w/o my walbro and tune for a while, no problems....

 

Do you think it can be fuel cut from the ECU?

 

Anyone else want to put an opinion please?

 

If anything, you're proably running too rich. Stock boost and stock fuel maps are very conservative and run rich in the first place. Isn't stock boost around 19 psi, anyway? Maybe at 14 psi WOT, too much fuel causing backfires in low gears. Higher gears, more load, bit higher boost, leaner mix, less backfire.

 

Stock boost on my meter is 10-11psi. OK does more air mean leaner or richer? I think it would be leaner but i may be wrong.

 

More air for a given amount of fuel is a leaner mixture. As for stock boost, I don't know, I drive a 2G DSM. But my brother's evo is stock, and I remember his being around 18. 10 or 11 seems pretty low.

 

stock boost is about 19 lbs. it is pretty low only running 14-15lbs try turning up your boost atleast to stock and see how that works for you

 

If stock boost is about 19psi then im definatly getting a wrong boost reading. I will try to get a better reading by switching the T to the fuel pressuer line. Now that i think about it, I might be trying to boost way past 20psi and im probably getting fuel cut.

 

for me it's sound cool