WG pressure only 6 psi boost?

[Brutal_r3drum]

i have a FP 18g and i have been running a ghetto boost controller that will let me hit 25lbs of boost. i dont want to run 25lbs daily, i disconnect the the boost controller and just ran the line from the j pipe to the wg, i cant afford a boost controller atm and would like to run more then 6lbs of boost. anyone have any ideas what could be causeing it? it stops building boost at 25 so i know its not stuck closed.

 

[420a_turbo]

i like how ppl are dogging me for tuning good a/fs and giving me shit for not getting a mbc to work... i have ran just wg pressure and it only hits like 6 psi. i think that the screw is to loose when its backed out.

what would be causing the 6psi from wg pressure? its a fp 18g and it should be like 15psi on wg pressre

I dont think anyone is intentionally trying to dog you, sorry if it comes across that way. Maybe you should abort the MBC you have and build a new one. I really think you would understand why people are coming across like that if you build one. Its really easy, $10-$20 tops in materials to make it.

As far as your boost issue, there are a lot of things that could contribute to it. Have you checked for any vac. leaks? Are you sure the WG is opening/closing correctly? The spring can wear out on those and cause similar issues. The WG stays closed to create boost, but once the required Vaccuum is in the WG it triggers it to open. The Vaccuum pulls against the spring to open the gate. A boost controller just bleeds off the vaccuum going to the WG so that it doesn't open, which causes the turbo to build more pressure. Im not sure what the exact formula is but if you are making say 18psi before the MBC, the bleed off will reduce that to say 10-12 or however much you open the Boost Controller. Opening it just bleeds the air into the atmosphere, reducing the vac. If you are pushing 20psi of boost, it still takes the same amount of vaccuum to open the WG as if you were pushing 12psi. The spring is only so strong, so you have to reduce the vaccuum to stop it from opening.

I hope that helps. If not, PM me and I will try and help more from there.


***edit***
I just saw you are in Bellevue, Im in Omaha so if you get to a point that you are ready to bang your head against the wall, PM me and I will try to meet you somewhere and give you a hand...