Hi, i just went a TII swap from a 86 na to a 91 S5 TII. This is my first turbo car ever and my first TII so i dont know too much about turbo boost. Everything seems to be fine except the fact that my greddy boost gauge doesnt even hit .5 bar. My car is running only about 5-6 psi. I have the following upgrades and was wondering if thats normal (which i dont think is since everyone seems to run at least 8psi).
-S5 motor with 34k and turbo 34k
-Greddy type S BOV
-Stock wastagate ( i was told its set at 7.5 or around there)
-Racing Beat full piping
-Racing Beat Fuel Cut Defenser
-Air pump removed
-i have no Boost controller
Thats about it as far as turbo is involved. I have checked the vacuum hoses along wastegate, turbo, BOV, Pressure sensor (little black box by pass side suspension in front), along with intercooler hoses. I have tried to listen and look for leaks by the EGR area where there are lots of hoses and couldnt hear or find anything. Im getting the block off plates which will get rid of the hoses in that EGR area and if there is a leak there then it will be solved but i dont think there is any. Anybody have any suggestions on why its running so low boost? What boost should it be running at with those mods, at least 8 right?

 

do you have racing bear FULL TURBO back or just cat back? if just cat back you are still going to be at stock boost. it turbo back than you should be at higher boost with it.

 

I have the Racing Beat Full piping from turbo back. What boost level should i be running at? any suggestions on why its not that psi i should be running?

 

i have a series five turbo on my 87 tii and a full 3 inch exhaust and can barfely break 6-7 psi

 

how many miles on the car and is it rebuilt?

 

The motor and turbo are both rebuild at 34k but that shouldnt matter because before the swap, the TII car was running past 8psi it got into an accident and motor was ok so they put it into my 86 NA. where Is the boost pressure sensor? and what is the little black box in the front off the front suspension on the pass side? Dont NA cars have that little box too?

 

Bump *help*

 

With the manifold pressure pushing directly on the waste gate spring, you are limited to what may be a tired spring.

The fix is cheap & easy - a manual boost controller.
I rigged mine with a solenoid bypass to run low boost most of the time (like your current level).
Then I flip the switch to engage the MBC.
I run 5-6 on low & 9-10 on high.

 

Thanks for the advice SureShot but the wastegate had been replaced with a stock one so i dont think its the spring in there. I noticed that the nozzle on the turbo which the hose connects to can spin around and seems loose but is that normal?

 

Also after paying more close attention to the greddy boost gauge, it hits only about 5psi through the whole RPM band. I was told its the boost solenoid but where is that?

 

you have the stock boost controler hooked up?

 

Do you mean the TID? If that's loose you need to fix it. If you're just talking about the nipples on the turbo itself, it's normal.

 

Stock boost controller? are you talking about the solenoid? I was told that maybe its my solenoid thats faulty and that its located by rats nest of vacuum tubes. Im going to be getting the emission block off plates and i think it gets rid of the solenoid so perhaps my boost will go up because i dont know what to check anymore. By the way what is the TIM? I have sprayed carb cleaner and there doesnt seem to be any changes in idle and i have inspected what i could around intercooler piping, vacuum lines, etc.
How hard is it to install the block off plates? im guessing its easy because im just taking things off and just bolting the plates where the holes are. Any suggestions or tips when i do get the plates in. Thank you.

 

sounds like you bypassed the S5 stock boost controller that BCTY mentioned. Did you run a hose directly from the nipple on the turbo to your wastegate? If so, then you will only see 5 psi as the stock S5 setup uses a boost controller to raise the boost.
-John

 

So the vacuum hose from the nipple on the turbo to the wastegate is suppose to have some stock boost controller in between there? Do you possibly have a pic of the stock setup cause the motor has already been modified before it was dropped into my car so i dont know any dont know anybody with a TII that i could look at. How are manual boost controller that XS engineering offers? any suggestions on which boost controller to get? i cant afford no $400 at the time. And also is it possible that its my electronic boost solenoid, im hoping it is since the block off plates will rid of it. Thanks

 

*help*

 

This is the one I'm using.
It's in the picture & chart I posted earlier.
http://cgi.ebay.com/ebaymotors/ws/eB...929256588&rd=1

Here is another one:
http://cgi.ebay.com/ebaymotors/ws/eB...930240051&rd=1

 

You can buy an aftermarket boost controller or there's a good thread around here somewhere on how to make one.
-John

 

im planning on going witht the XS engineering manual boost controller. any feedback on that? THe car is actually only peaking like at 3.5 psi *SAD*, after installing the manual boost controller and boost doesnt increase than that has to mean i have a leak somewehre that i couldnt find right?
Thanks for th help.

 

That is cool SureShot "The Force Is Strong With This One" .