ive been having this boost spike issue for about 2 weeks. i got tuned and it was fine..about a week or 2 later id do WOT and id hit boost cut..and it felt like i hit a invisible wall. i took off my mbc, my deltagate which was cracked(replaced it with a friends ebay tial) and just had one vacuum line to the turbo from the wastegate. that worked fine for about a day. i do a pull this morning and its spiking past 11 pounds.(im only tuned for 11 lbs right now) any help is appreciated. this is an annoying *** problem.

 

It's not a boost spike...it's a gift from god.

 

details on setup?

 

b18b motor
stock head
built block
560cc injectors
spoolin performance log mani
3" exhaust
2.5" downpipe
open dump
ebay "tial" wastegate
precision sc34 turbo

 

how are you running the lines for your wg/mbc? i mean, where are you sourcing the vac/boost points from

 

right now im running off of wastegate...just the vaccumm hose from the wastegate to the turbo housing

 

it should come from the intake for bes results

 

Here's a boost spike for you http://www.youtube.com/watch?v=nkNWl...eature=related

 

loosen the exhaust manifold nuts

but srsly, i have my wastegate dead center with all the runners on my log.. boost sits nice at .5 bar.. maybe the diaphram is stuck closed, take it apart and clean in. carefully reassemble and it should be fine..

reason I say that is, the used tial I have had some some issues opening by hand without a spring before I even ran it.. turns out the diaphram was sticky!