ok so if i drive and go full throttle and shift hard and high rpms and go through multiple gears by 3rd or 4th my boost will randomly go down to 10 psi at times when it normally and in all other gears sits at around 20 psi. i have a diode and a mbc at 20psi. everythign esle is stock except for a forge dv.

any ideas ? thanks

 

180/225? Sound like a boost leak. Have you played around with the MBC it see if same things occur? I'm not familiar with diode so I don't know what could be wrong in the area.

 

Its an rpm and load issue. Shift sooner since it sounds like you are shifting high and hitting the fall off of the turbos power

 

nah its not a shift/ load issue its just when i drive it hard through more then one or 2 gears and if if goes to 10 psi and i let my foot off the gas pedal for even a second and floor it it goes back to full (20) psi make turbo makes full power by about 3k and stays at 17-20 right till redline around 7 is when i shift.
its weird cuse its not ever time and its not the whole time, if it sits at 10 psi i can keep flooring it and all of the sudden it will "pop" back to 20 psi and be MUCH faster again

 

You don't make power in higher RPM's.

 

are you confused, my psi is going down to around 10 psi its not suppost to do this, the car even when stock never when down to 10 psi, now i run 20 psi and most of the time in any gears its at FULL 20 psi, and sometimes when doing pulls in mulitiple gears the psi goes down to 10 psi and it feels sluggish ( like it would if it was only running 10 psi)

the car when running 20 psi pulls all the way to redline and feels nice and quick, DO not confuse my car with the smaller turboed 180 i have the 225 with the ko4s and that car with that turbo pulls fine right to redline and does NOT run out of power at higher rpms.

still confused ??

 

Yes, to me your saying you have 10psi when you shift but, if you take it to redline you have 20psi. To me it sounds like you have a leak (EX: frayed fpr line or vac leak it could be a number of things. I don't know I'm nowhere near your car). I have a 225 with the ko4 & I get higher boost than you. & if you noticed I asked you eariler "180/225?" As in what model do you have.

 

perhaps the DV needs a higher rated spring and is being opened under higher pressure when shifting hard? as suggested, sounds like a loss of boost via some 'leak' or another... i had something similar on my Evo, and it was the waste gate 'flapping' due to the spring being too weak.

 

hmmm... my 225 has the same turbo you do and power dies out around 5700, producing about 24lbs w the Uni tune

I have doubts about these cars pulling hard past 6k

 

well i apologize for my misunderstanding then, ok it will at random times go to 20 psi and then suddenly in the same gear hit 10 psi and feel like a hit a brick wall and then after a second it will go back to 20psi or more, and other time in the same gears it will be fine and hit 20 psi and stay that way to redline. i feel like trying to make a video if i can. hmm
maybe this is an ignition problem ? ( i have stock plugs and i havent replaced them and im at 52k miles now its an 01)