boost spikes grrr

[Jabx]

I'm on the stock 14b using a Joe P. MBC for boost control and I have a ported 2G O2 housing and a ported 2G exhaust manifold.

It seems that lately my boost has been spiking really bad. It has always spiked some, but now with the boost set at 14 or 15 psi it spikes to 17 or 18 psi, then settle back in at 14 or 15.

Is there anything I can do to fix this?

 

[Boosted97GS-T]

mine spikes to 22psi then settles at 16psi so you not bad yet, i have yet to figure out whats the deal, i'm thinking its my damn joe p

 

[gst_spyder]

Try another MBC, I use a TXS hpmbc and don't get more then a 2psi spike. Oh and 6psi is sad man, thats just unacceptable!

Mario

 

[Jabx]

is it most likely my MBC? Because I don't want to get a new one and still have the same problem

 

[Tsigoon]

I have a home made one and I don't get ANY boost spike. Look around for the plans (I think on VFAQ) and TAKE YOUR TIME. I get rock solid boost with this one, so I'm Happy.

 

[gst_spyder]

You don't get ANY boost spike huh, I find this hard to believe Is yours a bleeder type or a ball/spring mbc?

Mario

 

[Formz]

I have the Joe P and get ZERO boost spike. It's not the MBC. Your O2 housing may need more porting, or your wastegate may need to be englarged.

 

[DMS-WhiteGSX]

i have a ball spring mbc and on the stock turbo i ddint get much spike.. on the big16 it just does whatever it wants... *shrug* 22psi is fineby me.

 

[Bohrn]

with my home made (ball and spring) mbc I get 1-2 psi spike, then steady at 15

I had a bigger spike, but I replaced the vacuum lines with larger diameter, stronger, thicker lines and it went away. My theory is that the line to the wastegate wasn't letting the signal get to it properly due to the soggyness of the old soft rubber.

best of luck