New b16g boost problems

[Mcgee16]

I just installed a new b16g ported with a 34mm WG. When i drive the car boost builds to 10 psi at 3800 rpm holds until 5000 rpm then climb's until i hit fuel cut at 15-16 psi. No matter where i set my mbc i cant get boost to build past 10-11 psi until it starts to creep at 5k. With my old t-25 i could hold 14 psi all day with out any creep. If anybody knows of anything that i should try let me no.

Thanks,
Scott

 

[Willjs7]

What 02 housing are you using? this may be the culprit. I have heard of too restrictive of an exhaust system creating boost creep.

 

[BacknBlack92ESi]

Ya the O2 might be it, and the downpipe. I also have a Big16G with the stock dp and 2 1/2" piping and I creep sometimes from 12 to 16. But im going to go with a 3" dp and a 3" O2.

 

[Mcgee16]

I have a 3in downpipe with no cat, 3 cat back. stock o2 housing. I figured that the o2 housing is the main problem. What o2 sensor housing do you suggest. I dont want to vent it into the atmosphere.

Thanks
Scott

 

[allezgrand]

If it is the O2 housing, you can get it ported, but if you want to test it to see if that is the problem, I would suggest simply taking off the O2 housing and driving it around completely open to see if the creep is being caused by restriction or if it's a problem in your wg actuator or MBC.

 

[Coldandafraid]

Originally posted by Mcgee16
No matter where i set my mbc i cant get boost to build past 10-11 psi until it starts to creep at 5k.

Is your mbc hooked up properly? or backwards?

 

[Mcgee16]

I made my mbc. And it is hooked up correctly. The only thing that doenst make sence is that it will hold 10-11 psi until 4500-5000 rpm then it spikes no matter were the mbc is set at. I hope that a new o2 sensor housing fixes it. I payed to have the 34mm flapper so that i didnt have this problem. Thanks for the help.


Scott

 

[Coldandafraid]

I doubt that an inadequate flowing o2 housing is what is preventing you from boosting past 10 psi no matter where you set your mbc. Since installing have you done a pressure test? What bov are you using? Hard intercooler pipes?

 

[Willjs7]

i think its the combonation of the stock 02 housing, and the crappy MBC i say get or borrow a working mbc. Hook it up correctly see if that fixes it, but its probably the 02 housing. So port it or by a ported evo or something.