boost not building-up :(
 

i'm running a B16 under 88 integra's hood since last one year. boosted the stock engine using EVO FMIC, 450cc DSMs, VAFC Hack, FPR, custom manifold and Nissan V27 turbo (boost was 8psi)
i use to feel not much ppower in third/fourth gear therefore i bought a new turbo formyeslf and it was a 16g(big). therefore i changed the manifold and got it designed like "ITTI" (means two 'T' connectors with two 'L' bends, i guess this is LOG style manifold?)
now my problem.
There is no leak in piping, rubber bends or in my intercooler. i use to get solid 8psi of boost with the older turbo. but after installing 16g with new manifold and downpipe. with stock actuator which was feeded from the charge pipe (hotside)
My first run with 16g
As soon as i floored it i just had 3/4psi , i was xpecting something around 8psi straight.
Then i UP the boost by tightning up the acctuator but still the boost was around 4psi
checked everything but notthing seems abnormal nor did i find any leaks. So in order to check how much is the turbo working i just opened up the acctuator pipe in order to monitor boost and floored it in third. boost went up to 15psi so i took the foot off my accelarator. So i bleeded the boost from the acctuator with a T fitting having a valve bleeding boost into the air. RESULTS. NO Bleed= 4psi, halfbleed=5psi , full bleeding=7psi..... even this 7psi was not constant/stable, had 5psi in first, 6psi in second in third boost went upto 9psi then came back to 7psi .

with acctutor (vacuum not connected) it use to spike upto 15psi and then came back to 6/7psi stable..... however in this case turbo should be giving full unlimited boost which my 16g didnt :(
im totally confused cuz im sure its not my acctuator, my turbo wastegate was perfectly fine, turbo spinsup real well and spins on idle too, turbo does not have shafplay(veryyyy minimum), there is no leak in pipe(hotter side or colder side) nor in my intercooler.

kindly help me in diagnosing the problem im ??? fuc***up
plez help

Re: boost not building-up :(
 

any exhaust leaks?
charge pipe leak!
or bad wastegate

Re: boost not building-up :(
 

@ exhaust leak = 0
charge pipe leak = 0
bad wastegate or acctuator = 0

None of above mentioned are faulty. i think its something else!

anyone had this kind of problem before? :(:(

Re: boost not building-up :(
 

there is nothing else, if you can make boost with the turbo and its big enuff then the turbo is ok.

then the charge pipes have to hold the boost to the engine(your surging shows they can)

so then you play with the wastegate and boost moves up and ----.

wastegate should eb your problem even if you think its ok

Re: boost not building-up :(
 

yea its probably your wastegate actuator, take it off and pull it in and out for like 10 minutes, cause the ebay ones tend to stick open, thats why your boost is fluctuating, give it a try, you never know man... ???

Re: boost not building-up :(
 

sounds like a internal

Re: boost not building-up :(
 

take your boost reference line off of the charge piping and run it from the intake manifold.
don't bleed boost with an internal wg.
get a ball and spring boost controller to run inline or make your own.
this will help boost response and prevent creep which is the problem you are having.

Re: boost not building-up :(
 

@whiterice: ill connect my vacuum source to my manifold instead on the charge pipe (hotter side, will also dissconnect my MBC). but i still thinkthat its something else other then wastegate/accutator issue, cuz even with no vacuum connected to wastegate/acctutor (where is should give huge amount of boost) it does not produc much boost.

BTW now!! my wastegate is very stricktly closed (streached acctuator) even then it produces 4/5psi of boost with huuuuge compressor surge :(:(


Its its very confusing for me :(

Yes!! all of my charge pipes are very much solid with no leaks (im damn sure on this). im not running the stock wastegate of 16g, instead i have another very much working wastegate mounted in the same way(likestock acctuator) on 16g. that wastegate works real well (i checked it myself, was pretty solid)
Vacuum source for wastegate acctuator is on the charge pipe(Hotter side) just after the turbo.
I also have a BOV which is working fine and vacuum/boost source is connect to it. its on the charge pipe(colder Side) around 15inches before the TB.

Boost controller is off now. even with the acctuator connected to the above specified vacuum source it gives me 4/5psi.

and with open wastegate acctuator(no vacuum lines connected) it goes upto 7/8psi in first , 10/11psi in second, 15psi in third but in third it drops back to 6/7 after hitting/holding up 15psi for a couple of secs :(.

I can hear huge turbo surge but not much sound in blow off valve.

Im thinking that turbo is spinning and producing boost but maybe an exhust realated issue???? restricted exhust??? car is quite like hell even in boost. i think i must give my car a run with open down pipe... what do u think?? cud this be the problem???
or my turbo manifold??? :(:(
guys plez help

Re: boost not building-up :(
 

sounds to me like your wastegate actuator is messed up. mine is an internal wastegate actuator and the diaphram inside must've broke cause the wastegate actator mount bolts came loose and the wastegate would stay open. I guess the extra stress from the wastegate mount being loose and putting presure on the internal actator's diaphram broke it and now a boost controler doesn't work on my car and I hear a low whistling noise comming from the wastegate actuator and the wistling noise goes away when I pinch the wastegate vacume hose so I know my wastegate's fucked up but it stil boost 7psi in 1st, 8-9psi in 2nd and up so I'm leaving it how it is. I use to be boosting 10psi but now it's only boosting 8-9psi I don't want to go through the trouble of buying and installing a new internal wastegate actuator just to get 1-2 more psi.

Re: boost not building-up :(
 

what bov are you using?